The origin of turtles: a paleontological perspective.

Science.gov (United States)

Joyce, Walter G

2015-05-01

The origin of turtles and their unusual body plan has fascinated scientists for the last two centuries. Over the course of the last decades, a broad sample of molecular analyses have favored a sister group relationship of turtles with archosaurs, but recent studies reveal that this signal may be the result of systematic biases affecting molecular approaches, in particular sampling, non-randomly distributed rate heterogeneity among taxa, and the use of concatenated data sets. Morphological studies, by contrast, disfavor archosaurian relationships for turtles, but the proposed alternative topologies are poorly supported as well. The recently revived paleontological hypothesis that the Middle Permian Eunotosaurus africanus is an intermediate stem turtle is now robustly supported by numerous characters that were previously thought to be unique to turtles and that are now shown to have originated over the course of tens of millions of years unrelated to the origin of the turtle shell. Although E. africanus does not solve the placement of turtles within Amniota, it successfully extends the stem lineage of turtles to the Permian and helps resolve some questions associated with the origin of turtles, in particular the non-composite origin of the shell, the slow origin of the shell, and the terrestrial setting for the origin of turtles. © 2015 Wiley Periodicals, Inc.

Seeking Shared Practice: A Juxtaposition of the Attributes and Activities of Organized Fossil Groups with Those of Professional Paleontology

Science.gov (United States)

Crippen, Kent J.; Ellis, Shari; Dunckel, Betty A.; Hendy, Austin J. W.; MacFadden, Bruce J.

2016-01-01

This study sought to define the attributes and practices of organized fossil groups (e.g., clubs, paleontological societies) as amateur paleontologists, as well as those of professional paleontologists, and explore the potential for these two groups to work collaboratively as a formalized community. Such an investigation is necessary to develop…

Supplement analysis for paleontological excavation at the National Ignition Facility at Lawrence Livermore National Laboratory

International Nuclear Information System (INIS)

1997-01-01

On December 15, 1997, contractor workers supporting the National Ignition Facility (NIF) construction uncovered bones suspected to be of paleontological importance. The NIF workers were excavating a utility trench near the southwest corner of the NIF footprint area, located at the northeast corner of the Lawrence Livermore National Laboratory (LLNL) Livermore Site, and were excavating at a depth of approximately 30 feet. Upon the discovery of bone fragments, the excavation in the immediate vicinity was halted and the LLNL archaeologist was notified. The archaeologist determined that there was no indication of cultural resources. Mark Goodwin, Senior Curator for the University of California Museum of Paleontology at the University of California, Berkeley, was then contacted. Mr. Goodwin visited the site on December 16th and confirmed that the bones consisted of a section of the skull, a portion of the mandible, several teeth, upper palate, and possibly the vertebrae of a mammoth, genus Mammuthus columbi. This supplement analysis evaluates the potential for adverse impacts of excavating skeletal remains, an activity that was only generally assessed by the NIF Project-Specific Analysis in the Final Programmatic Environmental impact Statement for Stockpile Stewardship and Management (SS and M PEIS) published in September 1996 (DOE/EIS-0236) and its Record of Decision published on December 19, 1996. This supplement analysis has been prepared pursuant to the DOE regulations implementing the National Environmental Policy Act (10 CFR 1021.314)

Extinctions. Paleontological baselines for evaluating extinction risk in the modern oceans.

Science.gov (United States)

Finnegan, Seth; Anderson, Sean C; Harnik, Paul G; Simpson, Carl; Tittensor, Derek P; Byrnes, Jarrett E; Finkel, Zoe V; Lindberg, David R; Liow, Lee Hsiang; Lockwood, Rowan; Lotze, Heike K; McClain, Craig R; McGuire, Jenny L; O'Dea, Aaron; Pandolfi, John M

2015-05-01

Marine taxa are threatened by anthropogenic impacts, but knowledge of their extinction vulnerabilities is limited. The fossil record provides rich information on past extinctions that can help predict biotic responses. We show that over 23 million years, taxonomic membership and geographic range size consistently explain a large proportion of extinction risk variation in six major taxonomic groups. We assess intrinsic risk-extinction risk predicted by paleontologically calibrated models-for modern genera in these groups. Mapping the geographic distribution of these genera identifies coastal biogeographic provinces where fauna with high intrinsic risk are strongly affected by human activity or climate change. Such regions are disproportionately in the tropics, raising the possibility that these ecosystems may be particularly vulnerable to future extinctions. Intrinsic risk provides a prehuman baseline for considering current threats to marine biodiversity. Copyright © 2015, American Association for the Advancement of Science.

Paleontology and stratigraphy of the Upper Triassic Kamishak Formation in the Puale Bay-Cape Kekurnoi-Alinchak Bay area, Karluk C-4 and C-5 quadrangle

Data.gov (United States)

Department of the Interior — This report summarizes the paleontological character and stratigraphy of the Kamishak Formation in the Puale Bay–Cape Kekurnoi–Alinchak Bay area, Karluk C-4 and C-5...

Chemical Mapping of Paleontological and Archeological Artifacts with Synchrotron X-Rays

Science.gov (United States)

Bergmann, Uwe; Manning, Phillip L.; Wogelius, Roy A.

2012-07-01

The application of the recently developed synchrotron rapid scanning X-ray fluorescence (SRS-XRF) technique to the mapping of large objects is the focus of this review. We discuss the advantages of SRS-XRF over traditional systems and the use of other synchrotron radiation (SR) techniques to provide corroborating spectroscopic and diffraction analyses during the same analytical session. After reviewing routine techniques used to analyze precious specimens, we present several case studies that show how SR-based methods have been successfully applied in archeology and paleontology. For example, SRS-XRF imaging of a seventh-century Qur'ān palimpsest and an overpainted original opera score from Luigi Cherubini is described. We also review the recent discovery of soft-tissue residue in fossils of Archaeopteryx and an ancient reptile, as well as work that has successfully resolved the remnants of pigment in Confuciusornis sanctus, a 120-million-year-old fossil of the oldest documented bird with a fully derived avian beak.

Paleontology and paleoecology of guano deposits in Mammoth Cave, Kentucky, USA

Science.gov (United States)

Widga, Chris; Colburn, Mona

2015-05-01

Bat guano deposits are common in the Mammoth Cave system (Kentucky, USA). Paleontological remains associated with these deposits are important records of local landscape changes. Recent excavations in the cave suggest that vertebrate remains in most of these deposits are dominated by Chiroptera. Although no extinct fauna were identified, the presence of a large roost of Tadarida brasiliensis in the Chief City section is beyond the northern extent of its current range suggesting that this deposit dates to an undetermined interglacial period. Stable isotope analyses of Tadarida-associated guano indicate a C3 prey signature characteristic of forested habitat. This was unexpected since this species is typically associated with open environments. Further ecomorphological analysis of wing shape trends in interglacial, Holocene, and historic-aged assemblages indicate that interglacial faunas are dominated by fast-flying, open-space taxa (T. brasiliensis) while late Holocene and Historic assemblages contain more taxa that utilized closed forest or forest gaps.

Stratigraphy and paleontology of fossil hill Peninsula Fildes, Rey Jorge island, Antarctica: a new approach

International Nuclear Information System (INIS)

Perea, D.; Masquelin, H.; Verde, M.; Guerequiz, R.

1998-01-01

Results of the first Uruguayan paleontologic and biostratigraphical investigations in Antarctica are presented.The field work was performed in Fildes Peninsula, King George Island, near the Uruguayan station Base Cientifica Antartida Artigas. Some fossiliferous outcrops were geologic and pale ontologically analyzed, among them the Fossil Hill, placed in the middle part of the peninsula, in front of Ardley Island between the Chinese and Chilean stations. This hill is composed of fossil bearing piroclastic and epiclastic rocks, assigned to the Fossil Hill Fm.Vegetal remains (petrified wood and leaf impronts)were observed and collected in this unit and it is remarkable the presence of Nothofagus sp. and invertebrate trace fossils Cochlichnus isp and Helminthopsis isp.

La colección de Paleontología de Vertebrados del Museo Nacional de Ciencias Naturales (CSIC

Directory of Open Access Journals (Sweden)

Alcalá, L.

1997-12-01

Full Text Available Since remote times, fossil vertebrates have played a significant part in the collections of the Spanish Museo Nacional de Ciencias Naturales, both in attracting the attention of the public and in the context of research into paleobiodiversity. The research tradition of the Museum’s personnel in Vertebrate Paleontology has built up a reference collection of information on the mammals of the Spanish Neogene. There are important fossils from almost a thousand different localities, some of them of worldwide relevancy. The collection is available for direct study in the Museum’s laboratories as well as through virtual conferences (www, and also being used in temporary exhibitions organized by the Museum itself or by other institutions.

Desde tiempos remotos, los vertebrados fósiles han formado parte significativa de las colecciones del Museo Nacional de Ciencias Naturales, tanto en la captación de la atención del público como en el contexto de la investigación sobre la paleobiodiversidad. La tradición investigadora del personal del Museo en Paleontología de Vertebrados ha originado una colección de referencia para el conocimiento de los mamíferos del Neógeno español. En total, se conservan importantes fósiles de casi un millar de localidades diferentes, algunas de ellas de relevancia mundial. La colección está disponible tanto para su estudio directo en el propio Museo como a través de consultas virtuales (www y también pueden utilizarse sus fondos en exposiciones temporales organizadas por el propio Museo o bien por otras instituciones.

Bibliometric analysis of authorship gender in the field vertebrate paleontology: Case study of Argentine journal Ameghiniana (1957-2011)

OpenAIRE

Miguel, Sandra; Hidalgo, Mónica; Stubbs, Edgardo; Posadas, Paula; Ortiz Jaureguizar, Edgardo

2013-01-01

El objetivo de este trabajo es determinar la existencia de diferencias de género en la distribución de las firmas de los trabajos de paleontología de vertebrados, analizando el caso de la revista argentina Ameghiniana, desde 1957 hasta 2011. Mediante el método bibliométrico se estudia la distribución y evolución por género de las firmas de los autores, su productividad, procedencia geográfica, composición de las firmas (autorías y coautorías), orden de mención de autores, taxón estudiado y ni...

Chinese paleontology and the reception of Darwinism in early twentieth century.

Science.gov (United States)

Yu, Xiaobo

2017-12-01

The paper examines the social, cultural and disciplinary factors that influenced the reception and appropriation of Darwinism by China's first generation paleontologists. Darwinism was mixed with Social Darwinism when first introduced to China, and the co-option of Darwinian phrases for nationalistic awakening obscured the scientific essence of Darwin's evolutionary theory. First generation Chinese paleontologists started their training in 1910s-1920s. They quickly asserted their professional identity by successfully focusing on morphology, taxonomy and biostratigraphy. Surrounded by Western paleontologists with Lamarckian or orthogenetic leanings, early Chinese paleontologists enthusiastically embraced evolution and used fossils as factual evidence; yet not enough attention was given to mechanistic evolutionary studies. The 1940s saw the beginning of a new trend for early Chinese paleontologists to incorporate more biological and biogeographical components in their work, but external events such as the dominance of Lysenkoism in the 1950s made the Modern Synthesis pass by without being publicly noticed in Chinese paleontology. Characterized by the larger goal of using science for nation building and by the utilitarian approach favoring local sciences, the reception and appropriation of Darwinism by first generation Chinese paleontologists raise important questions for studying the indigenizing efforts of early Chinese scientists to appropriate Western scientific theories. Copyright © 2017 Elsevier Ltd. All rights reserved.

JURASSIC PALEONTOLOGICAL HERITAGE OF MURCIA (BETIC CORDILLERA, SOUTH-EASTERN SPAIN

Directory of Open Access Journals (Sweden)

GREGORIO ROMERO

2004-03-01

Full Text Available Jurassic rocks of the External and Internal Zones of the Betic Cordillera are widespread in the province of Murcia. Four areas are considered of special interest for stratigraphical and paleontological analysis: a Sierra Quípar and b Sierras Lúgar-Corque (External Subbetic, c Sierra Ricote (Median Subbetic and d Sierra Espuña (Malaguide Complex. The first two contain Jurassic sections including Sinemurian-Tithonian deposits, and major stratigraphic discontinuities, containing significant cephalopod concentrations of taphonomic and taxonomic interest, occuring in the Lower-Upper Pliensbachian, Lower/Middle Jurassic and Middle/Upper Jurassic boundaries. These areas are also relevant for biostratigraphical analysis of the Middle-Upper Jurassic interval. In the Sierra de Ricote, the Mahoma section is of especial interest for the study of Lías/Dogger transition. Casa Chimeneas section constitutes the best Subbetic site for the analysis of the Lower/Upper Bajocian boundary. In the La Bermeja-Casas de Vite area, the Bajocian-Tithonian interval is well-represented, including a parastratotype of the Radiolarite Jarropa Formation. Finally, the Malvariche section in Sierra Espuña represents the best Jurassic succession of Internal Zones of the Betic Cordillera and could be considered as a reference section for this Betic Domain. In this paper a heritage evaluation has been carried out for these classical jurassic sections with the object of protecting these sites according to the legal framework prevailing in the province of Murcia.

Earth-Base: testing the temporal congruency of paleontological collections and geologic maps of North America

Science.gov (United States)

Heim, N. A.; Kishor, P.; McClennen, M.; Peters, S. E.

2012-12-01

Free and open source software and data facilitate novel research by allowing geoscientists to quickly and easily bring together disparate data that have been independently collected for many different purposes. The Earth-Base project brings together several datasets using a common space-time framework that is managed and analyzed using open source software. Earth-Base currently draws on stratigraphic, paleontologic, tectonic, geodynamic, seismic, botanical, hydrologic and cartographic data. Furthermore, Earth-Base is powered by RESTful data services operating on top of PostgreSQL and MySQL databases and the R programming environment, making much of the functionality accessible to third-parties even though the detailed data schemas are unknown to them. We demonstrate the scientific potential of Earth-Base and other FOSS by comparing the stated age of fossil collections to the age of the bedrock upon which they are geolocated. This analysis makes use of web services for the Paleobiology Database (PaleoDB), Macrostrat, the 2005 Geologic Map of North America (Garrity et al. 2009) and geologic maps of the conterminous United States. This analysis is a way to quickly assess the accuracy of temporal and spatial congruence of the paleontologic and geologic map datasets. We find that 56.1% of the 52,593 PaleoDB collections have temporally consistent ages with the bedrock upon which they are located based on the Geologic Map of North America. Surprisingly, fossil collections within the conterminous United States are more consistently located on bedrock with congruent geological ages, even though the USA maps are spatially and temporally more precise. Approximately 57% of the 37,344 PaleoDB collections in the USA are located on similarly aged geologic map units. Increased accuracy is attributed to the lumping of Pliocene and Quaternary geologic map units along the Atlantic and Gulf coastal plains in the Geologic Map of North America. The abundant Pliocene fossil collections

Ontogenetic Shape Change in the Chicken Brain: Implications for Paleontology.

Science.gov (United States)

Kawabe, Soichiro; Matsuda, Seiji; Tsunekawa, Naoki; Endo, Hideki

2015-01-01

Paleontologists have investigated brain morphology of extinct birds with little information on post-hatching changes in avian brain morphology. Without the knowledge of ontogenesis, assessing brain morphology in fossil taxa could lead to misinterpretation of the phylogeny or neurosensory development of extinct species. Hence, it is imperative to determine how avian brain morphology changes during post-hatching growth. In this study, chicken brain shape was compared at various developmental stages using three-dimensional (3D) geometric morphometric analysis and the growth rate of brain regions was evaluated to explore post-hatching morphological changes. Microscopic MRI (μMRI) was used to acquire in vivo data from living and post-mortem chicken brains. The telencephalon rotates caudoventrally during growth. This change in shape leads to a relative caudodorsal rotation of the cerebellum and myelencephalon. In addition, all brain regions elongate rostrocaudally and this leads to a more slender brain shape. The growth rates of each brain region were constant and the slopes from the growth formula were parallel. The dominant pattern of ontogenetic shape change corresponded with interspecific shape changes due to increasing brain size. That is, the interspecific and ontogenetic changes in brain shape due to increased size have similar patterns. Although the shape of the brain and each brain region changed considerably, the volume ratio of each brain region did not change. This suggests that the brain can change its shape after completing functional differentiation of the brain regions. Moreover, these results show that consideration of ontogenetic changes in brain shape is necessary for an accurate assessment of brain morphology in paleontological studies.

Absorption and Phase Contrast X-Ray Imaging in Paleontology Using Laboratory and Synchrotron Sources

Energy Technology Data Exchange (ETDEWEB)

Bidola, Pidassa; Stockmar, Marco; Achterhold, Klaus; Pfeiffer, Franz; Pacheco, Mirian L.A.F.; Soriano, Carmen; Beckmann, Felix; Herzen, Julia

2015-10-01

X-ray micro-computed tomography (CT) is commonly used for imaging of samples in biomedical or materials science research. Owing to the ability to visualize a sample in a nondestructive way, X-ray CT is perfectly suited to inspect fossilized specimens, which are mostly unique or rare. In certain regions of the world where important sedimentation events occurred in the Precambrian geological time, several fossilized animals are studied to understand questions related to their origin, environment, and life evolution. This article demonstrates the advantages of applying absorption and phase-contrast CT on the enigmatic fossil Corumbella werneri, one of the oldest known animals capable of building hard parts, originally discovered in Corumba (Brazil). Different tomographic setups were tested to visualize the fossilized inner structures: a commercial laboratory-based CT device, two synchrotron-based imaging setups using conventional absorption and propagation-based phase contrast, and a commercial X-ray microscope with a lens-coupled detector system, dedicated for radiography and tomography. Based on our results we discuss the strengths and weaknesses of the different imaging setups for paleontological studies.

Sedimentologic and paleontologic study of the southeast coast of Buenos Aires province, Argentina: A late Pleistocene Holocene paleoenvironmental reconstruction

Science.gov (United States)

Aramayo, S. A.; Téllez, B. Gutiérrez; Schillizzi, R. A.

2005-10-01

A paleoenvironmental reconstruction of the southeast coast of Buenos Aires province, Argentina, is made mainly on the basis of paleontological and paleoichnological studies, supported by sedimentological analyses and radiocarbon dating. Continental late Pleistocene and continental, transitional, and marine Holocene stratigraphic units are identified. The former comprises fossil mammals and ichnites of 16000-12,000 BP. The continental early Holocene time, ca. 8100 BP, is represented by an interdune paleoenvironment in which shallow brackish ponds were colonized by diatoms, fish, rodents, and birds. A transitional paleoenvironment in the middle Holocene—6930-6570 BP—is recorded by deposits formed by estuarine crabs. During the late Holocene, between 5000 and 4800 BP, a marine transgression was recorded by a rich mollusc fauna.

Ontogenetic Shape Change in the Chicken Brain: Implications for Paleontology.

Directory of Open Access Journals (Sweden)

Soichiro Kawabe

Full Text Available Paleontologists have investigated brain morphology of extinct birds with little information on post-hatching changes in avian brain morphology. Without the knowledge of ontogenesis, assessing brain morphology in fossil taxa could lead to misinterpretation of the phylogeny or neurosensory development of extinct species. Hence, it is imperative to determine how avian brain morphology changes during post-hatching growth. In this study, chicken brain shape was compared at various developmental stages using three-dimensional (3D geometric morphometric analysis and the growth rate of brain regions was evaluated to explore post-hatching morphological changes. Microscopic MRI (μMRI was used to acquire in vivo data from living and post-mortem chicken brains. The telencephalon rotates caudoventrally during growth. This change in shape leads to a relative caudodorsal rotation of the cerebellum and myelencephalon. In addition, all brain regions elongate rostrocaudally and this leads to a more slender brain shape. The growth rates of each brain region were constant and the slopes from the growth formula were parallel. The dominant pattern of ontogenetic shape change corresponded with interspecific shape changes due to increasing brain size. That is, the interspecific and ontogenetic changes in brain shape due to increased size have similar patterns. Although the shape of the brain and each brain region changed considerably, the volume ratio of each brain region did not change. This suggests that the brain can change its shape after completing functional differentiation of the brain regions. Moreover, these results show that consideration of ontogenetic changes in brain shape is necessary for an accurate assessment of brain morphology in paleontological studies.

Earth system science K-12 scientist-student partnerships using paleontological materials

Science.gov (United States)

Harnik, P. G.; Ross, R. M.; Chiment, J. J.; Sherpa, J. M.

2001-05-01

Reducing the discrepancy between the dynamic science that researchers experience and the static fact-driven science education in which k-12 students participate at school is an important component to national science education reform. Scientist-student partnerships (SSPs) involving whole classes in Earth systems research provide a solution to this problem, but existing models have often lacked rigorous scientific data quality control and/or evaluation of pedagogical effectiveness. The Paleontological Research Institution has been prototyping two SSPs with an eye toward establishing protocols to insure both scientific and educational quality of the partnership. Data quality analysis involves making statistical estimates of data accuracy and employing robust statistical techniques for answering essential questions with noisy data. Educational evaluation takes into account affective variables, such as student motivation and interest, and compares the relative pedagogical effectiveness of SSPs with more traditional hands-on activities. Paleontology is a natural subject for scientist-student partnerships because of its intrinsic appeal to the general public, and because its interdisciplinary content serves as a springboard for meeting science education standards across the physical and life sciences. The "Devonian Seas" SSP involves classes in identifying fossil taxa and assessing taphonomic characteristics from Devonian-aged Hamilton Group shales in Central New York. The scientific purpose of the project is to establish at high stratigraphic resolution the sequence of dysoxic biofacies composition, which will shed light on the sensitivity of epeiric sea communities to environmental (e.g., sea level) changes. The project is undertaken in upper elementary school and secondary school Earth science classes, and in some cases has involved field-based teacher training and collection of samples. Students in small teams collaborate to identify taxa within the samples, then

[50 years of the Revista de Biologia Tropical: its contribution to the development of the Geo-Paleontology].

Science.gov (United States)

Aguilar, Teresita

2002-06-01

The geosciences contribution along the 50 years of the Revista de Biología Tropical had been scarcity and episodic. Until now there are 2374 papers but only 21 (0.88%) have some relation with geological sciences. It's possible to recognize two periods with geological contributions, one between 1963 and 1978. It's appropriate to underline the importance of the biologist L. D. Gómez with his contributions about Costa Rican Paleobotanic in this period. The other period includes from 1988 to the present, and it's typified by an increase of biologist and geologist participation in different topics regarding with geosciences. Foreign and national researches are in the same ratio and belong from several countries like Costa Rica, México and Dominican Republic. The subjects are concerning mainly about fossil taxonomy (Paleontology: 81%), only 19% are related with geological topics. Such distribution could be explained because the affinity between the fossil studies and the biological sciences.

Punctuated Sediment Discharge during Early Pliocene Birth of the Colorado River: Evidence from Regional Stratigraphy, Sedimentology, and Paleontology

Science.gov (United States)

Dorsey, Rebecca J.; O'Connell, Brennan; McDougall, Kristin; Homan, Mindy B.

2018-01-01

discharge are assessed by comparing the depositional chronology to the record of global sea-level change. The lower Colorado River Valley and Salton Trough experienced marine transgression during a gradual fall in global sea level between 6.3 and 5.5 Ma, implicating tectonic subsidence as the main driver of latest Miocene relative sea-level rise. A major fall of global sea level at 5.3 Ma outpaced subsidence and drove regional delta progradation, earliest flushing of Colorado River sand into the northern Gulf of California, and erosion of Bouse basal carbonate and siliciclastic members. The lower Colorado River valley was re-flooded by shallow marine waters during smaller changes in global sea level 5.1-4.8 Ma, after the river first ran through it, which requires a mechanism to stop delivery of sand to the lower river valley. We propose that tectonically controlled subsidence along the lower Colorado River, upstream of the southern Bouse study area, temporarily trapped sediment and stopped delivery of sand to the lower river valley and northern Gulf of California for 200-300 kyr. Massive progradation of the fluvial-deltaic system back down the river valley into the Salton Trough starting 4.8-4.5 Ma apparently was driven by a huge increase in sediment discharge that overwhelmed the sediment-storage capacity of sub-basins along the lower river corridor and established the fully integrated river channel network. Accompanies Dorsey et al. "Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology". Accompanies Dorsey et al. "Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology". Accompanies Dorsey et al. "Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology".

Técnicas extractivas y preparativas en Paleontología: Aspectos ambientales y de seguridad laboral

Directory of Open Access Journals (Sweden)

Daniel L. Melendi

2009-06-01

y daño que afectan la salud así como de factores de riesgo y de probables conductas disfuncionales que los propician. Este trabajo, además de un breve análisis de los aspectos técnicos del trabajo paleontológico, presenta información de contexto, introduce en la problemática de los riesgos, expone los marcos normativos y desarrolla una interpretación de las posibles causas que explicarían el incumplimiento de lo establecido en materia de seguridad laboral. Propone también posibles estrategias destinadas a mitigar, corregir y revertir este problema.Extractive and preparation techniques in Paleontology. Environmental aspects and labor safety. The objective of this paper is to analyze the working conditions in which the paleontologic work is developed, especially in Paleopalynology and Paleovertebrat ology. This analysis is also valid for other academic and scientific activities. During fieldwork and in the paleontologic research a wide range of processes are applied, which proceed from the fields of physics and chemistry. They are characterized by different degrees of complexity and present different types of risks for the people who apply them, for other people, for physical objects and for the environment. For the applications of all these technical activities, some aspects must be taken into account that are not perceived as scientific matter and consequently do not receive attention: the safety of working conditions. This situation determines a state of precarious conditions of the labor environment and certain degree of stress, which potentiates the generation of accidents and damages and is hurting the legislation and the codes of professional ethics. The violation and absence of application of these rules are occurring frequently. The origin of this behavior may be due to the lack of knowledge and interest, and a certain degree of collective anomie that characterizes our society. In our labor environment -even without existing statistics- the cases

Lions as Bone Accumulators? Paleontological and Ecological Implications of a Modern Bone Assemblage from Olduvai Gorge.

Directory of Open Access Journals (Sweden)

Mari Carmen Arriaza

Full Text Available Analytic models have been developed to reconstruct early hominin behaviour, especially their subsistence patterns, revealed mainly through taphonomic analyses of archaeofaunal assemblages. Taphonomic research is used to discern which agents (carnivores, humans or both generate the bone assemblages recovered at archaeological sites. Taphonomic frameworks developed during the last decades show that the only large-sized carnivores in African biomes able to create bone assemblages are leopards and hyenas. A carnivore-made bone assemblage located in the short-grassland ecological unit of the Serengeti (within Olduvai Gorge was studied. Taphonomic analyses of this assemblage including skeletal part representation, bone density, breakage patterns and anatomical distribution of tooth marks, along with an ecological approach to the prey selection made by large carnivores of the Serengeti, were carried out. The results show that this bone assemblage may be the first lion-accumulated assemblage documented, although other carnivores (namely spotted hyenas may have also intervened through postdepositional ravaging. This first faunal assemblage potentially created by lions constitutes a new framework for neotaphonomic studies. Since lions may accumulate carcasses under exceptional circumstances, such as those documented at the site reported here, this finding may have important consequences for interpretations of early archaeological and paleontological sites, which provide key information about human evolution.

Lions as Bone Accumulators? Paleontological and Ecological Implications of a Modern Bone Assemblage from Olduvai Gorge.

Science.gov (United States)

Arriaza, Mari Carmen; Domínguez-Rodrigo, Manuel; Yravedra, José; Baquedano, Enrique

2016-01-01

Analytic models have been developed to reconstruct early hominin behaviour, especially their subsistence patterns, revealed mainly through taphonomic analyses of archaeofaunal assemblages. Taphonomic research is used to discern which agents (carnivores, humans or both) generate the bone assemblages recovered at archaeological sites. Taphonomic frameworks developed during the last decades show that the only large-sized carnivores in African biomes able to create bone assemblages are leopards and hyenas. A carnivore-made bone assemblage located in the short-grassland ecological unit of the Serengeti (within Olduvai Gorge) was studied. Taphonomic analyses of this assemblage including skeletal part representation, bone density, breakage patterns and anatomical distribution of tooth marks, along with an ecological approach to the prey selection made by large carnivores of the Serengeti, were carried out. The results show that this bone assemblage may be the first lion-accumulated assemblage documented, although other carnivores (namely spotted hyenas) may have also intervened through postdepositional ravaging. This first faunal assemblage potentially created by lions constitutes a new framework for neotaphonomic studies. Since lions may accumulate carcasses under exceptional circumstances, such as those documented at the site reported here, this finding may have important consequences for interpretations of early archaeological and paleontological sites, which provide key information about human evolution.

Lions as Bone Accumulators? Paleontological and Ecological Implications of a Modern Bone Assemblage from Olduvai Gorge

Science.gov (United States)

Arriaza, Mari Carmen; Domínguez-Rodrigo, Manuel; Yravedra, José; Baquedano, Enrique

2016-01-01

Analytic models have been developed to reconstruct early hominin behaviour, especially their subsistence patterns, revealed mainly through taphonomic analyses of archaeofaunal assemblages. Taphonomic research is used to discern which agents (carnivores, humans or both) generate the bone assemblages recovered at archaeological sites. Taphonomic frameworks developed during the last decades show that the only large-sized carnivores in African biomes able to create bone assemblages are leopards and hyenas. A carnivore-made bone assemblage located in the short-grassland ecological unit of the Serengeti (within Olduvai Gorge) was studied. Taphonomic analyses of this assemblage including skeletal part representation, bone density, breakage patterns and anatomical distribution of tooth marks, along with an ecological approach to the prey selection made by large carnivores of the Serengeti, were carried out. The results show that this bone assemblage may be the first lion-accumulated assemblage documented, although other carnivores (namely spotted hyenas) may have also intervened through postdepositional ravaging. This first faunal assemblage potentially created by lions constitutes a new framework for neotaphonomic studies. Since lions may accumulate carcasses under exceptional circumstances, such as those documented at the site reported here, this finding may have important consequences for interpretations of early archaeological and paleontological sites, which provide key information about human evolution. PMID:27144649

Building Baluchitherium and Indricotherium: imperial and international networks in early-twentieth century paleontology.

Science.gov (United States)

Manias, Chris

2015-01-01

Over the first decades of the twentieth century, the fragmentary remains of a huge prehistoric ungulate were unearthed in scientific expeditions in India, Turkestan and Mongolia. Following channels of formal and informal empire, these were transported to collections in Britain, Russia and the United States. While striking and of immense size, the bones proved extremely difficult to interpret. Alternately naming the creature Paraceratherium, Baluchitherium and Indricotherium, paleontologists Clive Forster-Cooper, Alexei Borissiak and Henry Fairfield Osborn struggled over the reconstruction of this gigantic fossil mammal. However, despite these problems, shared work on the creature served as a focus for collaboration and exchange rather than rivalry between these three scientific communities. Not only did the initial interpretation and analysis depend on pre-existing connections between British and American paleontological institutions, but the need for comparative material, recognition and contacts brought British and American scholars into communication and exchange with their counterparts in the Soviet Union. This article examines these processes. It first uses these excavations as a comparative case-study of different manifestations of colonial science in this period, examining how scholars in the Britain, the Russian Empire and the United States used formal and informal colonial links to Asia to pursue new research. It then moves to examine how the common problem of reconstructing this giant animal drew metropolitan scientific communities together, at least for a time. The construction of the Baluchitherium and Indricotherium illustrates the drives to expand research both imperially and internationally in the early-twentieth century, but also the continual problems in resources, institutionalization, transport and communication that could run up against scientific work.

Geology and mammalian paleontology of the Horned Toad Hills, Mojave Desert, California, USA

Science.gov (United States)

May, S.R.; Woodburne, M.O.; Lindsay, E.H.; Albright, L.B.; Sarna-Wojcicki, A.; Wan, E.; Wahl, D.B.

2011-01-01

The Horned Toad Formation includes five lithostratigraphic members that record alluvial fan, fluvial, lake margin, and lacustrine deposition within a relatively small basin just south of the active Garlock fault during the late Miocene to early Pliocene. These sediments experienced northwest-southeast contractional deformation during the Pliocene-Pleistocene associated with basement-involved reverse faults. Member Two of the Horned Toad Formation has yielded 24 taxa of fossil mammals, referred to as the Warren Local Fauna, including Cryptotis sp., cf. Scapanus, Hypolagus vetus, Hypolagus edensis,? Spermophilus sp., Prothomomys warrenensis n. gen., n. sp., Perognathus sp., Repomys gustelyi, Postcopemys valensis, Peromyscus sp. A, Peromyscus sp. B, Jacobsomys dailyi n. sp., Borophagus cf. B. secundus, cf. Agriotherium, Machairodus sp. cf. M. coloradensis, Rhynchotherium sp. cf. R. edensis, Pliomastodon vexillarius, Dinohippus edensis, Teleoceras sp. cf. T. fossiger, cf. Prosthennops, Megatylopus sp. cf. M. matthewi, Hemiauchenia vera, Camelidae gen. et. sp. indet., and the antilocaprid cf. Sphenophalos. The majority of fossil localities are confined to a 20 m thick stratigraphic interval within a reversed polarity magnetozone. The fauna demonstrates affinity with other late Hemphillian faunas from California, Nevada, Nebraska, Texas, and Mexico. The Lawlor Tuff, dated elsewhere in California at 4.83 ?? 0.04 Ma and geochemically identified in the Horned Toad Formation, overlies most of the fossil mammal localities. Magnetic polarity data are correlated with Chrons 3n.3r, 3n.3n, and 3n.2r, suggesting an age of approximately 5.0 - 4.6 Ma. These constraints indicate an age for the late Hemphillian Warren Local Fauna of 4.85 - 5.0 Ma. ?? Society of Vertebrate Paleontology November 2011.

Art in Paleontology: The Example of Manfred Reichel

Science.gov (United States)

Leria, M.; Ferràndez-Cañadell, C.

2013-12-01

Scientific illustration is a fundamental tool to communicate information through a form of nonverbal language with its own grammar and syntax. Contrary to the idea of scientific illustration as a simple scientific analytic tool, without a personal identity, we present an example where rigor is intrinsically linked to a high sensibility, and a deep knowledge of drawing that brings as a result a beautiful piece of art. In 1918 Manfred Reichel left his studies in Fine Arts (École des Beaux-Arts in Geneva, Switzerland) and began his career as a scientist, obtaining a degree in biological sciences from University of Neuchâtel. Humble by nature, he assumed he would not become a great artist, as he would tell his students. His point of view in micropaleontology, focused in foraminifera, protozoa with a complex shell, had an impact on his students and other specialists. His background in art benefited him in the research of the more complex foraminiferal structures, which he clarified by means of rich illustrations, with a high degree of beauty, inspired by the French naturalists. His research on the study of the shell of some foraminiferal groups, such as alveolinids, orbitolinids and fusulinids, produced some superb illustrations, which display their complex structure in such a comprehensible way that they could not be improved by modern techniques and are still used today. Reichel started teaching micropaleontology in 1935 at the Geologisch-Paläontologisches Institut of the University of Basel. As a professor of paleontology, he trained his students in drawing to enhance the level of description of their illustrations. When the interpretation turned out to be too difficult, he would encourage them to reconstruct the architecture of foraminifera, creating a 3D model, in order to visualize how the drawing should be. Due to his interest on ornithology and the mechanics of flight, he also created pictorial illustrations of birds, published in magazines and books. He used

Taphonomic and sedimentological aspects from PICOS II paleontological site, a quaternary pond deposit of Alagoas, Brazil

Science.gov (United States)

Asakura, Yumi; Silva, Jorge Luiz Lopes da; Silva, Ana Paula Lopes da; Silva, Elaine Pollyanne Alves da; Omena, Érica Cavalcante

2016-11-01

The Picos II Paleontological Site (PIIPS), located in the city of Piranhas, in Alagoas State, is a fossil deposit with a pond-like geomorphological feature, a kind of peculiar deposit for the Quaternary of Northeast Brazil. A detailed taphonomic study is presented about the PIIPS assemblage, from material collection to the laboratory analysis. The conservation state of the collected fossils in PIIPS is different from that found in other tank deposits, showing a high degree of specimen preservation. Two taxa of pleistocenic mammals have been identified: Eremotherium laurillardi and Notiomastodon platensis, and fragments of an avian bone, whose taxonomic identification was not possible. The taphonomic analysis indicates that the deposited material experienced a short transportation in high-energy event, with a short period of subaerial exposure before the final burial, where at least the final disarticulation occurred in situ, which explains the high conservation level of the material. The sedimentological analysis made in each layer of the deposit corroborates the information related to the transport of the material, which were obtained in taphonomic analysis. Regarding these aspects, PIIPS reflects nearly non-biased biocenotic patterns. The well-preserved material found in PIIPS demonstrates the great potential of deposits with pond-like geomorphological features, with sidelines that are less steep than traditional tanks, providing smoother transport and accommodation for skeletal elements, which is a distinguishing factor in preserving fossils of vertebrates.

Vertebrate paleontological exploration of the Upper Cretaceous succession in the Dakhla and Kharga Oases, Western Desert, Egypt

Science.gov (United States)

Sallam, Hesham M.; O'Connor, Patrick M.; Kora, Mahmoud; Sertich, Joseph J. W.; Seiffert, Erik R.; Faris, Mahmoud; Ouda, Khaled; El-Dawoudi, Iman; Saber, Sara; El-Sayed, Sanaa

2016-05-01

The Campanian and Maastrichtian stages are very poorly documented time intervals in Africa's record of terrestrial vertebrate evolution. Upper Cretaceous deposits exposed in southern Egypt, near the Dakhla and Kharga Oases in the Western Desert, preserve abundant vertebrate fossils in nearshore marine environments, but have not yet been the focus of intensive collection and description. Our recent paleontological work in these areas has resulted in the discovery of numerous new vertebrate fossil-bearing localities within the middle Campanian Qusier Formation and the upper Campanian-lower Maastrichtian Duwi Formation. Fossil remains recovered from the Campanian-aged Quseir Formation include sharks, rays, actinopterygian and sarcopterygian fishes, turtles, and rare terrestrial archosaurians, including some of the only dinosaurs known from this interval on continental Africa. The upper Campanian/lower Maastrichtian Duwi Formation preserves sharks, sawfish, actinopterygians, and marine reptiles (mosasaurs and plesiosaurs). Notably absent from these collections are representatives of Mammalia and Avialae, both of which remain effectively undocumented in the Upper Cretaceous rocks of Africa and Arabia. New age constraints on the examined rock units is provided by 23 nannofossil taxa, some of which are reported from the Duwi Formation for the first time. Fossil discoveries from rock units of this age are essential for characterizing the degree of endemism that may have developed as the continent became increasingly tectonically isolated from the rest of Gondwana, not to mention for fully evaluating origin and diversification hypotheses of major modern groups of vertebrates (e.g., crown birds, placental mammals).

50 años de la Revista de Biología Tropical: Contribución al desarrollo de la Geo-Paleontología

Directory of Open Access Journals (Sweden)

Teresita Aguilar

2002-06-01

Full Text Available Las contribuciones sobre temas geocientíficos en los 50 años de la Revista de Biología Tropical ha sido muy escaza y episódica. De los 2i374 artículos publicados hasta la fecha, solamente 21 (0.88% tienen alguna relación con las geociencias. Se pueden reconocer dos etapas de aportes relacionados con las ciencias geológicas, la primera entre 1963 - 1978, destacándose en ésta época los trabajos sobre la paleobotánica de Costa Rica realizados por el biólogo L. D. Gómez. La segunda etapa se inicia en 1988 y se continúa hasta la actualidad, con un incremento en la participación de biólogos y geólogos. La participación relativa entre nacionales y extranjeros ha sido muy equilibrada y los lugares tratados incluyen en orden de importancia Costa Rica, México, República Dominicana y algunos de interés general. Los temas han sido principalmente sobre diversos campos de la Paleontología (81%, constituyendo los temas netamente geológicos sólo el 19%. Esto se puede explicar por la mayor afinidad que existe entre el estudio de los fósiles y la BiologíaThe geosciences contribution along the 50 years of the Revista de Biología Tropical had been scarcity and episodic. Until now there are 2374 papers but only 21 (0.88% have some relation with geological sciencies. It`s posible to reconize two periods with geological contributions, one between 1963 and 1978. It`s appropiate to underline the importance of the biologist L. D. Gómez with his contributions about Costa Rican Paleobotanic in this period. The other period includes from 1988 to the present, and it`s tipyfied by an increase of biologist and geologist participation in different topics regarding with geosciences. Foreing and national researches are in the same ratio and belong from several contries like Costa Rica, México and Dominican Repubic. The subjects are concerning mainly about fossil taxonomy (Paleontology: 81%, only 19% are related with geological topics. Such

Quaternary Geochronology, Paleontology, and Archaeology of the Upper San Pedro River Valley, Sonora, Mexico

Science.gov (United States)

Gaines, E. P.

2013-12-01

This poster presents the results of multi-disciplinary investigations of the preservation and extent of Quaternary fossil-bearing strata in the San Pedro River Valley in Sonora, Mexico. Geologic deposits in the portions of the San Pedro Valley in southern Arizona contain one of the best late Cenozoic fossil records known in North America and the best record of early humans and extinct mammals on the continent. The basin in the U.S. is one of the type locations for the Blancan Land Mammal Age. Hemiphilian and Irvingtonian fossils are common. Rancholabrean remains are widespread. Strata in the valley adjacent to the international border with Mexico have yielded the densest concentration of archaeological mammoth-kill sites known in the western hemisphere. Despite more than 60 years of research in the U.S., however, and the fact that over one third of the San Pedro River lies south of the international boundary, little has been known about the late Cenozoic geology of the valley in Mexico. The study reported here utilized extensive field survey, archaeological documentation, paleontological excavations, stratigraphic mapping and alluvial geochronology to determine the nature and extent of Quaternary fossil-bearing deposits in the portions of the San Pedro Valley in Sonora, Mexico. The results demonstrate that the Plio-Pleistocene fossil -bearing formations known from the valley in Arizona extend into the uppermost reaches of the valley in Mexico. Several new fossil sites were discovered that yielded the remains of Camelids, Equus, Mammuthus, and other Proboscidean species. Late Pleistocene archaeological remains were found on the surface of the surrounding uplands. AMS radiocarbon dating demonstrates the widespread preservation of middle- to late- Holocene deposits. However, the late Pleistocene deposits that contain the archaeological mammoth-kill sites in Arizona are absent in the valley in Mexico, and are now known to be restricted to relatively small portions of

Paleontological overview of oil shale and tar sands areas in Colorado, Utah, and Wyoming.

Energy Technology Data Exchange (ETDEWEB)

Murphey, P. C.; Daitch, D.; Environmental Science Division

2009-02-11

In August 2005, the U.S. Congress enacted the Energy Policy Act of 2005, Public Law 109-58. In Section 369 of this Act, also known as the ''Oil Shale, Tar Sands, and Other Strategic Unconventional Fuels Act of 2005,'' Congress declared that oil shale and tar sands (and other unconventional fuels) are strategically important domestic energy resources that should be developed to reduce the nation's growing dependence on oil from politically and economically unstable foreign sources. In addition, Congress declared that both research- and commercial-scale development of oil shale and tar sands should (1) be conducted in an environmentally sound manner using management practices that will minimize potential impacts, (2) occur with an emphasis on sustainability, and (3) benefit the United States while taking into account concerns of the affected states and communities. To support this declaration of policy, Congress directed the Secretary of the Interior to undertake a series of steps, several of which are directly related to the development of a commercial leasing program for oil shale and tar sands. One of these steps was the completion of a programmatic environmental impact statement (PEIS) to analyze the impacts of a commercial leasing program for oil shale and tar sands resources on public lands, with an emphasis on the most geologically prospective lands in Colorado, Utah, and Wyoming. For oil shale, the scope of the PEIS analysis includes public lands within the Green River, Washakie, Uinta, and Piceance Creek Basins. For tar sands, the scope includes Special Tar Sand Areas (STSAs) located in Utah. This paleontological resources overview report was prepared in support of the Oil Shale and Tar Sands Resource Management Plan Amendments to Address Land Use Allocations in Colorado, Utah, and Wyoming and PEIS, and it is intended to be used by Bureau of Land Management (BLM) regional paleontologists and field office staff to support future

PALEONTOLOGY

Institute of Scientific and Technical Information of China (English)

2007-01-01

<正>20072695 Hu Bin(Henan Polytechnic University,Jiaozuo,Henan 454003);Jiang Zaixing Trace Fossils of Deeper Lacustrine Deposits in the Paleogene Shahejie Formation of Jiyang Depression,Shandong Province,East China(Acta Palaeontologica Sinica,ISSN0001-6616,CN32-1188/Q,45(1),2006,p.83-94,1 illus.,2 plates,1 table,18 refs.)Key words:ichnofossils,Jiyang Depression The Paleogene Shahejie Formation of Jiyang Depression,Shandong Province,Eastern China,

Galactic Paleontology

NARCIS (Netherlands)

Tolstoy, Eline

Individual low-mass stars have very long lives, comparable to the age of the universe, and can thus be used to probe ancient star formation. At present, such stars can be identified and studied only in the Milky Way and in the very closest of our neighboring galaxies, which are predominantly small

SEQUENCE STRATIGRAPHY AND PALEONTOLOGY OF THE UPPER MIOCENE PISCO FORMATION ALONG THE WESTERN SIDE OF THE LOWER ICA VALLEY (ICA DESERT, PERU

Directory of Open Access Journals (Sweden)

CLAUDIO DI CELMA

2017-04-01

Full Text Available The sequence stratigraphic framework and a summary of the fossil fauna of the upper Miocene portion of the Pisco Formation exposed along the western side of the Ica River (southern Peru is presented through a new geological map encompassing an area of about 200 km2 and detailed chronostratigraphic analyses. Extensive field mapping and sedimentological study of outcrop sections have shown that the Pisco Formation is a cyclical sediment unit composed of at least three fining-upward, unconformity-bounded depositional sequences, designated P0, P1, and P2 from oldest to youngest. In the study area, these sequences progressively onlap a composite basal unconformity from southwest to northeast. Integration of biostratigraphic and tephrochronologic age determinations constrains the ages of the three Pisco sequences within the study area. Based on the age of surrounding sediments, a conservative estimate of the age of P0 suggests deposition of these strata between 17.99 ± 0.10 Ma and 9.00 ± 0.02 Ma, whereas diatom biostratigraphy and calculated 40Ar/39Ar ages converge to indicate that strata of the P1 sequence were deposited sometime between 9.5 Ma and 8.9 Ma and that those of the P2 sequence are younger than 8.5 Ma and older than 6.71 ± 0.02 Ma. Our survey for both vertebrate and macro-invertebrate remains in the three sequences confirms the outstanding paleontological value of the Pisco Formation and contributes to depict regional faunal shifts in the fossil assemblage.

Alometría y dimorfismo sexual del fémur de Homo sapiens y Homo neanderthalensis en un contexto evolutivo

OpenAIRE

Anaya García, Noelia; Rosas, Antonio; Bastir, Markus; Estalrrich, Almudena; García-Tabernero, Antonio; Huguet, Rosa; Rasilla, Marco de la; Pastor, Francisco

2015-01-01

Comunicación presentada en el XIII Encuentro en Jóvenes Investigadores en Paleontología (XIII EJIP) - XIII Meeting of Early-Stage Researchers in Paleontology (XIII EJIP): Cercedilla, 15 - 18 de Abril de 2015

A new window to an old world: reconstructing the Middle Eocene of Messel for Hessisches Landesmuseum Darmstadt

OpenAIRE

Sanisidro, Óscar; Micklich, Norbert; Sandrock, Oliver

2015-01-01

Comunicación presentada en el XIII Encuentro en Jóvenes Investigadores en Paleontología (XIII EJIP) - XIII Meeting of Early-Stage Researchers in Paleontology (XIII EJIP): Cercedilla, 15 - 18 de Abril de 2015

Factual states of affairs – uniting diverging philosophical orientations ...

African Journals Online (AJOL)

The problem of persistence and change and the state of affairs that change can only be detected on the basis of constancy permeated the history of philosophy and the various academic disciplines, including the discipline of paleontology. The dominant pattern of the paleontological record, namely stasis, poses empirical ...

La contribución del Nuevo Mundo al nacimiento de las ciencias paleontológicas (The contribution of the New World to the birth of the paleontological Sciences

Directory of Open Access Journals (Sweden)

Miguel León Garrido

2016-05-01

Full Text Available Resumen: Este trabajo presenta una aproximación a la contribución del Nuevo Mundo al nacimiento y consolidación de las ciencias paleontológicas, haciendo especial énfasis en la relación científica entre España y las colonias americanas. Los hallazgos de fósiles americanos influyeron poderosamente en los cambios de paradigma que tuvieron lugar en las ciencias naturales entre la Edad Moderna y los inicios de la Edad Contemporánea. Los estudiosos americanos no se limitaron al descubrimiento y envío de muestras a las instituciones europeas para su estudio, sino que formularon sus propias teorías interpretativas y llevaron a cabo aportaciones novedosas y pioneras en el campo de la geología americana. El diálogo científico entre la España y sus colonias se vio interrumpido tras las Guerras de Emancipación.Abstract: This paper presents an approach to the contribution of the New World to the birth and consolidation of paleontological sciences, with special emphasis on the scientific relationship between Spain and its American colonies. American fossil findings powerfully influenced the paradigm changes that took place in the natural sciences among the Modern Age and the beginnings of the Contemporary Age. American Scientifics were not only dedicated to the discovery and sending of samples to the European institutions for their study, but also made their own interpretative theories and carried out innovative and pioneering contributions in the knowledge about the Geology of America.The scientific dialogue between Spain and its colonies was interrupted after the Wars of Emancipation.

Zur Geschichte der Geowissenschaften im Museum für Naturkunde zu Berlin. Teil 6: Geschichte des Geologisch-Paläontologischen Instituts und Museums der Universität Berlin 1910–2004

Directory of Open Access Journals (Sweden)

W. Gross

2004-01-01

Full Text Available Die Entwicklung des Geologisch-Paläontologischen Instituts und Museums der Universität Berlin von einer Institution, die Geologie zusammen mit Paläontologie als eine Einheit vertrat, über eine Institution, die eine geotektonische Ausrichtung hatte, zu einer auf Paläontologie konzentrierten Institution wird nachvollzogen. Die beiden Institutsdirektoren am Anfang des 20sten Jahrhunderts waren Vertreter der allumfassenden Geologie des 19ten Jahrhunderts, während die beiden folgenden Direktoren eine Geologie ohne Paläontologie vertraten. Das führte zu einer Trennung der beiden Richtungen, und nach der III. Hochschulreform der DDR 1968 verblieb allein die sammlungsbezogene Paläontologie am Museum. Nach der Wiedervereinigung wurde ein Institut für Paläontologie mit biologischer Ausrichtung mit zwei Professuren, einer für Paläozoologie und einer für Paläobotanik, eingerichtet. The development of the Geologisch-Paläontologisches Institut und Museum of the Museum für Naturkunde at the Humboldt University (formerly Friedrich-Wilhelm-Universität in Berlin from a geology-paleontology institution to a pure paleontology institution is described. The first two directors of the department in the beginning of the 20th century, Prof, von Branca and Prof. Pompeckj, represented a 19th century concept of a geology, which included paleontology, even vertebrate paleontology as the crown jewel of geology. They fought sometimes vigorously against a separation of paleontology from geology. The next two directors. Prof. Stille and Prof, von Bubnoff, were the leading geologists in Germany; to be a student of Stille was a special trade mark in geology of Germany. They represented a geology centered on tectonics. The separation of paleontology as separate section was prepared. The destructions of the Second World War, the following restaurations and the division of Germany into two States influenced strongly their directorships. The education of geologists

Recepción temprana de la teoría de la deriva continental y su competencia con las teorías rivales

Directory of Open Access Journals (Sweden)

Pérez-Malváez, Carlos

2003-06-01

Full Text Available In 1912 Alfred Lothar Wegener proposed the theory of the continental drift. Wegener thought that the displacement explained more paleontological and geophysical data than any other rival program. The great virtue of the drift theory resided in their great capacity of synthesis. Wegener appealed to the information provided by the Geology, Paleontology and Paleoclimatology.

Alfred Lothar Wegener propuso la teoría de la deriva continental en 1912. Wegener ciertamente pensó que el desplazamiento explicaba mas datos paleontológicos y geofísicos que cualquiera de los programas de investigación establecidos. Desde luego, la gran virtud de la teoría de la deriva fue su gran capacidad de síntesis. Wegener recurrió a la información que provenía de la Geología, Geofísica, Paleontología y Paleoclimatología.

78 FR 30810 - Paleontological Resources Preservation

Science.gov (United States)

2013-05-23

..., maintaining confidentiality of specific locality data, and authorizing penalties for illegal collecting, sale... the general mining laws, the mineral or geothermal leasing laws, laws providing for minerals materials... with certain non-agency personnel for scientific, educational, or resource management purposes, without...

Wedel (2006) SVP Poster - sauropod neck elongation

OpenAIRE

Wedel, Mathew

2013-01-01

The poster I presented at the 2006 annual meeting of the Society of Vertebrate Paleontology. The blue 'updated' boxes in the abstract represent changes I made between submitting the abstract and presenting the poster. The abstract appeared as: Wedel, M.J. 2006. Pneumaticity, neck length, and body size in sauropods. Journal of Vertebrate Paleontology 26(3):137A. The email and webpage info at the top of the poster are now out of date. My personal webpage is now http://sauroposeidon.wordpr...

The Carboniferous-Permian boundary in the central western Argentinean basins: paleontological evidences El límite Carbonífero-Pérmico en las cuencas del centro oeste de Argentina: evidencias paleontológicas

Directory of Open Access Journals (Sweden)

Gabriela A Cisterna

2011-07-01

Full Text Available The central western Argentinean basins of Río Blanco, Calingasta-Uspallata and western Paganzo, enclose the most complete marine successions used for examining the Carboniferous-Permian boundary in Gondwana. A detailed review of the key stratigraphical sections has allowed the identification of the latest Carboniferous assemblages; NBG, Interval megafloristic Zone and DM (Raistrickia densa-Convolutispora muriornata Palynological Zone in the lower part, and the earliest Permian T-S (Tivertonia jachalensis-Streptorhynchus inaequiornatus invertebrate Zone and FS (Pakhapitesfusus-Vittatina subsaccata Palynological Zone in the upper part. This diagnostic mega/microflora and marine invertebrate paleontological evidence provides a biostratigraphical framework for the definition of the Carboniferous-Permian boundary inside the basins of central western Argentina.Las cuencas del centro oeste de Argentina, Río Blanco, Calingasta-Uspallata y el sector oeste de la cuenca Paganzo, contienen las secuencias marinas más completas para el estudio del límite Carbonífero-Pérmico en Gondwana. Un estudio detallado de secciones estratigráficas claves ha permitido la identificación de las asociaciones megaflo-rísticas NBG y de Intervalo, y de la palinozona DM (Raistrickia densa-Convolutispora muriornata, del Carbonífero Tardío, en la parte inferior de dichas secciones; en tanto, en la parte media superior de las secciones estudiadas, se han identificado la biozona de invertebrados T-S (Tivertonia jachalensis-Streptorhynchus inaequiornatus y la palinozona FS (Pakhapites fusus-Vittatina subsaccata, ambas asignadas al Pérmico Temprano. El registro de estas asociaciones diagnósticas de mega/microflora e invertebrados marinos provee un esquema bioestratigráfico integrado que permite ubicar el límite Carbonífero-Pérmico en las cuencas del centro oeste de Argentina.

Desenvolvimento de Atividade Lúdica para o Auxílio do Ensino e Divulgação Científica da Paleontologia.

Directory of Open Access Journals (Sweden)

Diogo Jorge de Melo

2007-07-01

Full Text Available Herein is described the development of a ludical activity in Paleontology with the purpose to apply the concepts of the geological time and the processes that occurred along the history of the Earth. This activity,that was teste in the event “Bio na Rua” of the Universidade Federal do Rio de Janeiro, consisted on the use ofdidactic panels concerning paleontological themes, geological time chart, fossil and ichnofossil concepts, the development of a board game showing the Earth history and origami workshops.

Dating the Time of Origin of Major Clades: Molecular Clocks and the Fossil Record

Science.gov (United States)

Smith, Andrew B.; Peterson, Kevin J.

Molecular and paleontological data provide independent means of estimating when groups of organisms evolved in the geological past, but neither approach can be considered straightforward. The single most fundamental obstacle to developing an accurate estimate of times of origination from gene sequence data is variation in rates of molecular evolution, both through time and among lineages. Although various techniques have been proposed to circumvent this problem, none unambiguously allow the components of time and rate to be separated. Furthermore, problems of establishing accurate calibration points, correctly rooted phylogenies, and accurate estimates of branch length remain formidable. Conversely, paleontological dates fix only the latest possible time of divergence, and so probabilistic methods are required to set a lower boundary on origination dates. Realistic confidence intervals that take preservational biases into account are only just becoming available. Although molecular and paleontological approaches to dating often agree reasonably well, there are two notable areas of disagreement; when mammal and bird orders originated and when the major phyla originated. The discrepancy in dating bird/mammal ordinal origins probably reflects a global rock-record bias. Paleontological sampling in the Late Cretaceous is still too restricted geographically to draw any firm conclusions about the existence of a pre-Tertiary record for modern orders of bird or mammal from anywhere other than North America. Dating the time of origin of phyla is more complicated, and is confounded by both preservational biases and problems of molecular clock estimation.

Possible Origin of Stagnation and Variability of Earth's Biodiversity

Science.gov (United States)

Stollmeier, Frank; Geisel, Theo; Nagler, Jan

2014-06-01

The magnitude and variability of Earth's biodiversity have puzzled scientists ever since paleontologic fossil databases became available. We identify and study a model of interdependent species where both endogenous and exogenous impacts determine the nonstationary extinction dynamics. The framework provides an explanation for the qualitative difference of marine and continental biodiversity growth. In particular, the stagnation of marine biodiversity may result from a global transition from an imbalanced to a balanced state of the species dependency network. The predictions of our framework are in agreement with paleontologic databases.

3D CENTRAL LINE EXTRACTION OF FOSSIL OYSTER SHELLS

Directory of Open Access Journals (Sweden)

A. Djuricic

2016-06-01

Full Text Available Photogrammetry provides a powerful tool to digitally document protected, inaccessible, and rare fossils. This saves manpower in relation to current documentation practice and makes the fragile specimens more available for paleontological analysis and public education. In this study, high resolution orthophoto (0.5 mm and digital surface models (1 mm are used to define fossil boundaries that are then used as an input to automatically extract fossil length information via central lines. In general, central lines are widely used in geosciences as they ease observation, monitoring and evaluation of object dimensions. Here, the 3D central lines are used in a novel paleontological context to study fossilized oyster shells with photogrammetric and LiDAR-obtained 3D point cloud data. 3D central lines of 1121 Crassostrea gryphoides oysters of various shapes and sizes were computed in the study. Central line calculation included: i Delaunay triangulation between the fossil shell boundary points and formation of the Voronoi diagram; ii extraction of Voronoi vertices and construction of a connected graph tree from them; iii reduction of the graph to the longest possible central line via Dijkstra’s algorithm; iv extension of longest central line to the shell boundary and smoothing by an adjustment of cubic spline curve; and v integration of the central line into the corresponding 3D point cloud. The resulting longest path estimate for the 3D central line is a size parameter that can be applied in oyster shell age determination both in paleontological and biological applications. Our investigation evaluates ability and performance of the central line method to measure shell sizes accurately by comparing automatically extracted central lines with manually collected reference data used in paleontological analysis. Our results show that the automatically obtained central line length overestimated the manually collected reference by 1.5% in the test set, which

D Central Line Extraction of Fossil Oyster Shells

Science.gov (United States)

Djuricic, A.; Puttonen, E.; Harzhauser, M.; Mandic, O.; Székely, B.; Pfeifer, N.

2016-06-01

Photogrammetry provides a powerful tool to digitally document protected, inaccessible, and rare fossils. This saves manpower in relation to current documentation practice and makes the fragile specimens more available for paleontological analysis and public education. In this study, high resolution orthophoto (0.5 mm) and digital surface models (1 mm) are used to define fossil boundaries that are then used as an input to automatically extract fossil length information via central lines. In general, central lines are widely used in geosciences as they ease observation, monitoring and evaluation of object dimensions. Here, the 3D central lines are used in a novel paleontological context to study fossilized oyster shells with photogrammetric and LiDAR-obtained 3D point cloud data. 3D central lines of 1121 Crassostrea gryphoides oysters of various shapes and sizes were computed in the study. Central line calculation included: i) Delaunay triangulation between the fossil shell boundary points and formation of the Voronoi diagram; ii) extraction of Voronoi vertices and construction of a connected graph tree from them; iii) reduction of the graph to the longest possible central line via Dijkstra's algorithm; iv) extension of longest central line to the shell boundary and smoothing by an adjustment of cubic spline curve; and v) integration of the central line into the corresponding 3D point cloud. The resulting longest path estimate for the 3D central line is a size parameter that can be applied in oyster shell age determination both in paleontological and biological applications. Our investigation evaluates ability and performance of the central line method to measure shell sizes accurately by comparing automatically extracted central lines with manually collected reference data used in paleontological analysis. Our results show that the automatically obtained central line length overestimated the manually collected reference by 1.5% in the test set, which is deemed

Dinosaurs in the year of Darwin.

Science.gov (United States)

Dodson, Peter

2009-09-01

This special issue of The Anatomical Record explores the recent advances in the functional morphology and paleobiology of dinosaurs. Although Darwin did not study dinosaurs because paleontology was in its infancy a century and half ago, he considered both paleontology and anatomy as essential subjects for establishing the validity of evolution. The study of dinosaurs constitutes a vigorous subdiscipline within vertebrate paleontology, and anatomists and evolutionary functional morphologists constitute an especially creative subgroup within dinosaur paleontology. The collection of 17 papers presented in this issue encompass cranial anatomy, postcranial anatomy, and paleobiology of dinosaurs and other archosaurs. Soft tissue subjects include studies of brain structure, jaw adductor muscles, and keratinous appendages of the skull. Taxonomically, it includes four papers with a focus on theropods, including Tyrannosaurus, five papers dealing with ceratopsians, three papers on hadrosaurs, and one on ankylosaurs. Modern anatomical techniques such as CT scanning, finite element analysis, and high resolution histology are emphasized. The visual presentation of results of these studies is spectacular. Results include the first-ever life history table of a plant-eating dinosaur; a determination of the head orientation of Tyrannosaurus and its relatives based on interpretation of the semicircular canals. The claws of Velociraptor appear to best adapted for tree climbing, but not for horrific predatory activities. Pachyrhinosaurus evidently used its massive head for head butting. The tail club of the armored dinosaur Euoplocephalus had the structural integrity to be used as a weapon. The pages abound with insights such as these. Dinosaurs once dead for millions of years live again! (c) 2009 Wiley-Liss, Inc.

Paleoecology and environments of bioestromes and path reefs , its ostreid , enhdolith and epibionts ( Camacho formation - middle upper Miocene; Uruguay)

International Nuclear Information System (INIS)

Sprechmann, P.; Verde, M.; Martinez, S.; Gaucher, C.

1998-01-01

A special lithofacies of the Camacho formation (Middle-Upper Miocene, Uruguay), exposed at Puerto Arazati, is studied from a sedimentologic and paleontologic point of view. Ostreid biostromes and patch reefs show different kinds of growings patterns. Two kinds of ostreid concentration s, biogenic and sedimentologic were distinguished in Puerto Arazati based on taphonomic evidence. Endolith association and epibionts from biostrome and patch reef hardgrounds were also analysed in Puerto Arazati. Both sedimentologic and paleontologic evidence indicates a free of sediment, shallow water depositional environment, in the photic zone. Complementary data about endoliths from other outcrops of the Camacho Formation are included (author)

Occurance and expansion: if it was not so?

Directory of Open Access Journals (Sweden)

Ratnikov Viatcheslav Yurievich

2013-10-01

Full Text Available The author criticizes some hypotheses of amphibians and reptiles occurrence and expansion, including those on the basis of data phylogeography interpretation,suggested by herpetologists. Using molecular data, it is impossible to define, where subspecies has appeared and how its area varied. The method of definition of species appearance time requires very serious correlation by means of paleontological data. It is also impossible to identify approximate time of the subspecies occurrence, defined by molecular data, with the time of its modern area occupation. We can assume it, analyzing paleontological findings and paleogeographical conditions at that time, but not vice versa.

78 FR 66064 - Notice of Intent To Prepare a Livestock Grazing Monument Management Plan Amendment and Associated...

Science.gov (United States)

2013-11-04

...-level decisions associated with livestock grazing, thereby amending the GSENM Management Plan. DATES..., archaeology, paleontology, wildlife and fisheries, hydrology, soils, sociology and economics, and public...

77 FR 5833 - Notice of Availability of the Draft Programmatic Environmental Impact Statement for Allocation of...

Science.gov (United States)

2012-02-06

..., such as lands with wilderness characteristics, visual resources, ecological resources, and cultural...; paleontology; hydrology; soils; sociology; and economics. The BLM will use and coordinate public participation...

75 FR 20376 - Notice of Availability of the Draft Environmental Impact Statement/Staff Assessment and Possible...

Science.gov (United States)

2010-04-19

..., paleontological, and geologic resources; recreation; land use; noise; public health; socioeconomics; and traffic..., transmission line safety, and nuisance. Additionally, the applicant has applied to the Department of Energy...

Proceedings of the 14. Symposium on Geology from Northeast

International Nuclear Information System (INIS)

1991-01-01

Works on geology, including topics about sedimentology, stratigraphy, paleontology, geomorphology, environmental, hydrogeology, petrology, geochemistry, geochronology, geophysics, geotectonics and structural geology are described in this symposium. (C.G.C.)

75 FR 51477 - Grand Staircase-Escalante National Monument, Monument Advisory Committee: Call for Nominations

Science.gov (United States)

2010-08-20

... financial disclosure requirements in the Ethics in Government Act and 5 CFR 2634. Travel reimbursement is... expertise: Archaeology; Botany; Geology; Paleontology; Social science; Systems ecology; and Wildlife biology...

78 FR 5834 - Notice of Intent To Prepare a Supplemental Environmental Impact Statement and Resource Management...

Science.gov (United States)

2013-01-28

... incorporate and observe the principles of multiple use and sustained yield; (12) The Roan Plateau RMP..., archaeology, paleontology, lands and realty, hydrology, soils, sociology, and economics. Authority: 40 CFR...

76 FR 9632 - Notice of Final Federal Agency Actions on Proposed Highway in California

Science.gov (United States)

2011-02-18

... Landmarks/Paleontology: National Historic Preservation Act of 1966; Historic Sites Act of 1935; Antiquities... Act; Fish and Wildlife Coordination Act; Migratory Bird Treaty Act. 8. Wetlands and Water Resources...

75 FR 69120 - National Natural Landmark Designations

Science.gov (United States)

2010-11-10

... springs and associated late Pleistocene bone beds. Many types of animals, especially large herbivores... development of scientific thought on the concept of extinction and the relationship of geology/paleontology...

PROTEOMICS AND MASS SPECTROMETRY FOR ARCHAEOLOGY AND PALEONTOLOGY

OpenAIRE

De Chiaro, Addolorata

2017-01-01

The preservation of cultural heritage is central for protecting a sense of who we are, a meaningful reference in our culturally diverse world. (1) Efforts to preserve resources on cultural heritage have gained new momentum throughout the world nowadays. The protection of our cultural heritage is a cultural but also economical process. (1) It is nowadays broadly recognized that chemical analysis of materials can contribute to this process with important and often crucial information tha...

Paleontological excavations in designated wilderness: theory and practic

Science.gov (United States)

Christopher V. Barns

2000-01-01

Wilderness is widely recognized as a valuable environment for scientific research, and it is generally assumed that this research will benefit the wilderness resource. But what if the research is of value only in understanding an ecosystem that has been extinct for 65 million years? What if thousands of pounds of material must be removed from the wilderness to conduct...

Archaeological and Paleontological Salvage at Barbers Point, Oahu

Science.gov (United States)

1978-03-01

Ewa Plain, a former coral-algae calcareous reef that emerged following the post-Pleistocene sea-level subsidence. The topography that usually results...endangered floral species are present in this area, as well as several other rare and uncommon plants . No endangered species of fauna are recorded from...larger pits was used for cultivation and even today one comes upon bananas and Hawaiian sugarcane still growing in them [McAllister 1933:1091

Transformace vědeckého skandálu

Czech Academy of Sciences Publication Activity Database

Cílek, Václav

2015-01-01

Roč. 94, č. 1 (2015), s. 3-3 ISSN 0042-4544 Institutional support: RVO:67985831 Keywords : science * scientometry * scientific discoveries * paleontology * sediments * fossil * Proterozoic Subject RIV: DB - Geology ; Mineralogy

Determination of lanthanides in fossil samples using laser induced breakdown spectroscopy

International Nuclear Information System (INIS)

Anzano, J.M.; Lasheras, R.J.; Canudo, I.; Laguna, M.

2017-01-01

As being a fast, simple and relatively non-destructive analytical technique Laser-induced breakdown spectroscopy (LIBS) has a large variety of applications including the analysis of paleontological samples. In this work LIBS is employed for the quantitative determination of lanthanides (Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Sm, Tb, Tm and Yb) in vertebrate fossil samples comprising teeth, disarticulated complete or fragmented bones, eggshell fragments, and coprolites of dinosaurs, mammals and crocodiles. For emission line data, standard AnalaR grade salts of lanthanides were used. The major components: iron, calcium, magnesium, silicon and aluminum in the samples were also determined. The analytical information may be helpful in studying the samples for their age, formation environment and other paleontological properties. (author)

Alexandr Pavlovich Rasnitsyn, (palaeoentomologist extraordinaire – a personal appreciation

Directory of Open Access Journals (Sweden)

Denis Brothers

2011-09-01

Full Text Available This note is not meant to be an exhaustive account of the many achievements of Alex Rasnitsyn over the 75 years of his life thus far. Apart from anything else, I have little knowledge of his activities outside of my professional interactions with him. Also, there will undoubtedly be several other biographical essays this year to celebrate his accomplishments in many fields. So, my intention, after providing the essential details to place him in context, mainly derived from his personal page on the Paleontological Institute’s website (Rasnitsyn 2011 and a note in the Paleontological Journal (Laboratory of Arthropods, in press, is to give my personal impressions of our interactions, his influence on my own life and work, and on hymenopterology in general.

75 FR 17431 - Notice of Availability of the Draft Environmental Impact Statement/Staff Assessment for the...

Science.gov (United States)

2010-04-06

..., paleontological, and geological resources; recreation; land use; noise; public health; socioeconomics; and traffic... engineering, transmission line safety, and nuisance. A Notice of Intent to Prepare an EIS/SA and Proposed Land...

Paleofaunal and Environmental Research on Miocene Fossil Sites TVOR SE and TVOR S on Fort Polk, Louisiana, with Continued Survey, Collection, Processing, and Documentation of other Miocene Localities

National Research Council Canada - National Science Library

Schiebout, Judith

2004-01-01

Focus of paleontological research on the Miocene of Fort Polk is currently the marine locality TVOR SE, which also has yielded large and small terrestrial Miocene vertebrates, and a single Cretaceous...

Minutes

International Nuclear Information System (INIS)

1998-01-01

In the minutes of II Uruguayan Geological Congress have been included the following topics: structural geology, tectonic, sedimentology, stratigraphy, mineralogy, petrology, geochemistry, paleontology, mineral prospecting, economic, regional and applied geology. (author)

Late Glacial–Holocene record of benthic foraminiferal ...

Indian Academy of Sciences (India)

K Verma

2018-03-06

Mar 6, 2018 ... influence of oxygen-rich Antarctic Intermediate Water (AAIW). Keywords. Paleontology; benthic ..... nent changes at millennial scale are noticed during certain intervals ...... become environmental change? The proxy record of ...

Revision of Pennsylvanian genus .i.Sturia./i. Němejc and its spores (Duckmantian, Czech Republic)

Czech Academy of Sciences Publication Activity Database

Frojdová, Jana; Pšenička, J.; Bek, Jiří

2017-01-01

Roč. 57, č. 2 (2017), s. 153-163 ISSN 2082-0259 Institutional support: RVO:67985831 Keywords : Sturia * ferns * Carboniferous * aphlebiae * sporangia * in situ spores Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology

PLANETARY PERMO-СARBONIFEROUS ICE AGE – BANK OF PALEONTOLOGICAL AND GEOLOGICAL FACTS FOR DISPROVING THE GLACIAL THEORY

Directory of Open Access Journals (Sweden)

V. G. Chuvardinsky

2017-09-01

��s multi-year research has proved that “exaration” types of relief of the Quaternary time (fjords, skerries, lake basins in bedrock, drumlins were formed due to the disjunctive dislocations of different rank and sequence. They occupy their normal place in the ensemble of paragenetic structures that accompany faulting. A detailed study of fault systems, especially shifts and zones of their dynamic influence, showed a paragenetic connection of the most striking “exaration” types of relief (roche moutonnée (sheepbacks, fleecy rock, rocks polishing, striations and furrows with structures such as near-surface thrusts, upcast faults, downcast faults and shifts. Mass development of the above-mentioned relief forms is observed at the ends of the large shifts and they are made of fault planes and slickensides of the listed near-surface disjunctive structures upthrow sides of which are mostly destroyed into a blocky-boulder component. There is rich paleontological material concerning the period of vast Permo-Carboniferous glaciation that covered virtually the entire globe, this material allows reconstructing actual landscapes and climates of that epoch. Extremely favorable conditions for the development of terrestrial vegetation were created in the Carboniferous period. Warm, humid climate dominated in vast territories of the globe. A sultry, heavy atmosphere reigned in the Carboniferous forests. The deposits of coal amounting to nearly 30 % of the world’s reserves of this fuel were formed. And climate of the Permian period was generally the warmest of the formerly dominated Paleozoic. Tillites. Considering that the remnants of the Paleozoic vegetation are often found in the cut layers of the tillites, and the tillites are interbedded with the lenses and layers of coal, it is high time to recall that the tillites are a tectonic breccia, tectonic melange, and boulders with scars and striations are the most reliable indicator of their tectono-dynamic processing. As for the

Prof. RNDr. Vladimír Homola, CSc., významná osobnost ve výzkumu Českého krasu

Czech Academy of Sciences Publication Activity Database

Žák, Karel; Cílek, Václav; Grmela, A.

2014-01-01

Roč. 40, č. 1 (2014), s. 19-26 ISSN 1211-1643 Institutional support: RVO:67985831 Keywords : Bohemian Karst * speleology * karstology * caves * geology * paleontology * hydrogeology * Vladimír Homola Subject RIV: DB - Geology ; Mineralogy

Education: Bioscience Education through Bioparks.

Science.gov (United States)

Robinson, Michael H.

1988-01-01

Suggests creating a biological park to stress the interrelationships between plants and animals. States that the techniques of a zoo should be applied to paleontology, anatomy, anthropology. Gives advantages of this creative concept. (RT)

Pas de Vallgornera Cave, Majorca (Spain): one the largest littoral caves in Europe; La cueva des Pas de Vallgornera, Mallorca (Espana): unas de las cuevas litorales mas grandes de Europa

Energy Technology Data Exchange (ETDEWEB)

Lopez, B.; Mulet, T.; Rodriguez-Homar, M.; Merino, A.

2016-07-01

The Pas de Vallgornera cave is the longest cave in the Balearic Islands and one of the largest in Europe (more than 73 km long). It is found on the Miocene reef of Llucmajor Platform and its genesis is related to the development of normal faults and associated fracture systems with N 180° S and N 60° E orientation that took place during the Neogene. It is noteworthy for the abundance, variety and beauty of the speleothems, paleontological richness and to present evidence of hypogene basal recharge. Due to its singularity, it has served as the basis of several scientific studies on groundwater level fluctuations during the quaternary period and others related to the existence of one of most important paleontological sites in Mallorca as far as vertebrates are concerned. (Author)

Impact Theory of Mass Extinctions and the Invertebrate Fossil Record

Science.gov (United States)

Alvarez, Walter; Kauffman, Erle G.; Surlyk, Finn; Alvarez, Luis W.; Asaro, Frank; Michel, Helen V.

1984-03-01

There is much evidence that the Cretaceous-Tertiary boundary was marked by a massive meteorite impact. Theoretical consideration of the consequences of such an impact predicts sharp extinctions in many groups of animals precisely at the boundary. Paleontological data clearly show gradual declines in diversity over the last 1 to 10 million years in various invertebrate groups. Reexamination of data from careful studies of the best sections shows that, in addition to undergoing the decline, four groups (ammonites, cheilostomate bryozoans, brachiopods, and bivalves) were affected by sudden truncations precisely at the iridium anomaly that marks the boundary. The paleontological record thus bears witness to terminal-Cretaceous extinctions on two time scales: a slow decline unrelated to the impact and a sharp truncation synchronous with and probably caused by the impact.

Fulltext PDF

Indian Academy of Sciences (India)

Unknown

ranging from paleontology (Crônier et al 1998) to developmental biology .... i.e. those that equally integrate different techniques and levels of investigation, are ... P A 1997 Extreme environmental change and evolution (Cambridge: Cambridge.

Science News of the Year.

Science.gov (United States)

Science News, 1983

1983-01-01

Highlights important 1983 news stories reported in Science News. Stories are categorized under: anthropology/paleontology; behavior; biology; chemistry; earth sciences; energy; environment; medicine; physics; science and society; space sciences and astronomy; and technology and computers. (JN)

Mayfly Burrows in Firmground of Recent Rivers from the Czech Republic and Poland, with Some Comments on Ephemeropteran Burrows in General

Czech Academy of Sciences Publication Activity Database

Uchman, A.; Mikuláš, Radek; Stachacz, M.

2017-01-01

Roč. 24, č. 3 (2017), s. 191-203 ISSN 1042-0940 Institutional support: RVO:67985831 Keywords : Ephemeroptera * ichnology * lebensspuren * fluvial environment Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.182, year: 2016

Stopy v hlubokých mořích. Pozůstatky po činnosti bezobratlých v hlubokomořských horninách

Czech Academy of Sciences Publication Activity Database

Mikuláš, Radek

2014-01-01

Roč. 93, č. 6 (2014), s. 338-342 ISSN 0042-4544 Institutional support: RVO:67985831 Keywords : invertebrates * sea invertebrates * marine sediments * fossils * paleontology * sea floor * clastic sediments * turbidity current * Turkey Subject RIV: DB - Geology ; Mineralogy

The origin of continents and oceans

National Research Council Canada - National Science Library

Wegener, Alfred 1880-1930; Biram, John

1966-01-01

... and Antarctica up through the Indian Ocean, and closing the remaining gaps. Wegener then explained various phenomena in historical geology, geomorphy, paleontology, paleoclimatology, and similar areas of science in terms of this continental drift."--From back cover.

Dynamics of various viral groups infecting autotrophic plankton in Lake Geneva

Digital Repository Service at National Institute of Oceanography (India)

Parvathi, A.; Zhong, X.; Jacquet, S.

both the presence and relative abundance of bands using the GelCompare II software package (Applied Maths, Kortrijk, Belgium) and the Paleontological Statistics Software Package for education and Software analysis (PAST version 2.14) (Hammer et al...

Tracing the evolution of avian wing digits.

Science.gov (United States)

Xu, Xing; Mackem, Susan

2013-06-17

It is widely accepted that birds are a subgroup of dinosaurs, but there is an apparent conflict: modern birds have been thought to possess only the middle three fingers (digits II-III-IV) of an idealized five-digit tetrapod hand based on embryological data, but their Mesozoic tetanuran dinosaur ancestors are considered to have the first three digits (I-II-III) based on fossil evidence. How could such an evolutionary quirk arise? Various hypotheses have been proposed to resolve this paradox. Adding to the confusion, some recent developmental studies support a I-II-III designation for avian wing digits whereas some recent paleontological data are consistent with a II-III-IV identification of the Mesozoic tetanuran digits. A comprehensive analysis of both paleontological and developmental data suggests that the evolution of the avian wing digits may have been driven by homeotic transformations of digit identity, which are more likely to have occurred in a partial and piecemeal manner. Additionally, recent genetic studies in mouse models showing plausible mechanisms for central digit loss invite consideration of new alternative possibilities (I-II-IV or I-III-IV) for the homologies of avian wing digits. While much progress has been made, some advances point to the complexity of the problem and a final resolution to this ongoing debate demands additional work from both paleontological and developmental perspectives, which will surely yield new insights on mechanisms of evolutionary adaptation. Copyright © 2013 Elsevier Ltd. All rights reserved.

USING GIS FOR ORGANIZATION AND MANAGEMENT OF GEOLOGIC SPECIALLY PROTECTED NATURAL AREAS

Directory of Open Access Journals (Sweden)

A. V. Shurkhovetskiy

2017-01-01

Full Text Available The article describes approaches to the preservation of unique geological objects used in the world and in Russia. It lists the shortcomings of geological monuments of nature as the main form of protection of territories that have specific features of geological structure and significant paleontological locations. It also proves the relevance of geoinformation systems (GIS use for a comprehensive solution of existing problems.The article describes the main features of the algorithm for the GIS development in the projected Alexandrov-Balykleysky geopark, consisting of a number of sequentially performed operations: field and office research, development of a cartographic basis, creation of thematic layers and database, development of conventional designations system and user interface elements.It justifies the division of information available for different user categories by creating specialized thematic layers and their relevant attributive tables, and by including additional information materials in the database. It gives conventional designations examples of geological monuments of nature of various types (paleontological, geological-geomorphological, geologicalpaleontological and sculpture-paleontological and geological sections of various stratigraphic divisions.The obtained results may be used to justify the creation and development of geoparks, to improve the management efficiency of existing geological protected areas, to conduct scientific research and to monitor the state of facilities, to collect, systematize and analyze new data, as well as for the development of tourism, culture, environmental education by creating an information Internet resource and compiling a wide range of educational products: maps, atlases, booklets, etc. 

Sedimentation and paleoecology of Pliocene lagoonal-shallow marine deposits on the island of Rhodes (Greece)

NARCIS (Netherlands)

Broekman, J.A.

1974-01-01

A detailed analysis of the depositional and paleontological characteristics of a section of the Pliocene Kritika Formation on the island of Rhodos is presented. The environmental significance of sedimentary structures, the paleoecology of benthonic Foraminifera, and the sequentional

Managing Climate Change Refugia for Climate Adaptation

Science.gov (United States)

The concept of refugia has long been studied from theoretical and paleontological perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change ref...

The Vertebral Formula of the African Sideneck Turtle ( Pelusios ...

African Journals Online (AJOL)

Pelusios castaneus), was carried out with the view of deriving its vertebral formula which could be useful in the comparative systematic anatomy of sea and freshwater turtles as well as in paleontological and archaeological investigations. A total ...

75 FR 54698 - Sentencing Guidelines for United States Courts

Science.gov (United States)

2010-09-08

...'' after ``Resources''; by inserting ``or paleontological resource'' before ``, loss''; by striking ``cultural heritage'' after ``to that'' and by striking ``cultural heritage'' after ``of the''. The... Destruction of, Cultural Heritage Resources; Unlawful Sale, Purchase, Exchange, Transportation, or Receipt of...

Increasing knowledge on biodiversity patterns and climate changes in Earth's history by international cooperation: introduction to the proceedings IGCP 596/SDS Meeting Brussels (2015)

Czech Academy of Sciences Publication Activity Database

Mottequin, B.; Slavík, Ladislav; Königshof, P.

2017-01-01

Roč. 97, 3 SI (2017), s. 367-374 ISSN 1867-1594 Institutional support: RVO:67985831 Keywords : editorial material * Earth's history * biodiversity * climate changes Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.278, year: 2016

Nejstarší doklad existence svalové tkáně? Nové zkameněliny z konce starohor

Czech Academy of Sciences Publication Activity Database

Mikuláš, Radek

2015-01-01

Roč. 94, č. 1 (2015), s. 31-34 ISSN 0042-4544 Institutional support: RVO:67985831 Keywords : paleontology * fossil s * Eumetazoa * Cnidaria * Bilateralia * Ediacaran fauna * Proterozoic * muscle tissue * fossil footprints * movement of animals Subject RIV: DB - Geology ; Mineralogy

An endemic ichnoassemblage from a late Miocene paleolake in SE Iceland

Czech Academy of Sciences Publication Activity Database

Pokorný, R.; Krmíček, Lukáš; Sudo, M.

2017-01-01

Roč. 485, 1 November 2017 (2017), s. 761-773 ISSN 0031-0182 Institutional support: RVO:67985831 Keywords : Turbidite * Mermia ichnofacies * Thorichnus-Vatnaspor ichnoassemblage Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 2.578, year: 2016

El hombre como animal: el antropocentrismo en la zoología

Directory of Open Access Journals (Sweden)

Viejo Montesinos, José Luis

1996-12-01

Full Text Available Zoological taxonomy and nomenclature have always been subject to great anthropocentrism. Since Linnaeus, most of classifications place Man in a preeminent and unique position among animals, may be as a Greek culture heritage ("Man is the measure of everything". This prejudice has sometimes given rise to an ethnocentric explanation of the evolution and human paleontology.

La taxonomía y la nomenclatura zoológicas han estado siempre sometidas a un considerable antropocentrismo. Desde Linneo, la mayoría de las clasificaciones colocan al hombre en un lugar preeminente y único entre los animales, quizá como herencia de la cultura griega ("El hombre es la medida de todas las cosas". Este prejuicio ha conducido a veces hacia una interpretación etnocéntrica de la evolución y la paleontología humana.

A Carboniferous chiton (Mollusca, Polyplacophora) at the end of its trail: a unique find from the Czech Republic

Czech Academy of Sciences Publication Activity Database

Mikuláš, Radek; Rindsberg, A. K.; Santos, A.; Pavela, M.

2017-01-01

Roč. 56, č. 2 (2017), s. 171-179 ISSN 0375-7633 Institutional support: RVO:67985831 Keywords : Viséan * Recent * locomotion traces * tracemakers * Proleptochiton Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 0.903, year: 2016

76 FR 46355 - Notice of Statute of Limitations on Claims; Notice of Final Federal Agency Actions on Proposed...

Science.gov (United States)

2011-08-02

...); Rehabilitation Act [29 U.S.C. 794]. 6. Paleontology: Antiquities Act of 1906 [16 U.S.C. 431-433]; Federal-Aid... Bird Treaty Act [16 U.S.C. 703-712]. 12. Executive Orders (EO) 12898 Federal Actions to Address...

Systematics and paleobiogeography of .i.Sardolagus obscurus./i. n. gen. n. sp. (Leporidae, Lagomorpha) from the early Pleistocene of Sardinia

Czech Academy of Sciences Publication Activity Database

Angelone, Ch.; Čermák, Stanislav; Moncunill-Solé, B.; Quintana, J.; Tuveri, C.; Arca, M.; Kotsakis, T.

2018-01-01

Roč. 92, č. 3 (2018) ISSN 0022-3360 Institutional support: RVO:67985831 Keywords : Sardolagus obscurus n. gen. n. sp. * Leporidae * early Pleistocene * Sardinia * systematics Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.591, year: 2016

77 FR 21803 - Notice of Intent To Amend the Resource Management Plan for the Rawlins Field Office and...

Science.gov (United States)

2012-04-11

...; water quality; vegetation management; recreation, cultural resource, and paleontological resource... planning process: Air quality, cultural resources, fire and fuels management, forest management, lands and... fisheries, lands and realty, hydrology, soils, sociology and economics, and wild horses. Authority: 40 CFR...

Bajpai, Prof. Sunil

Indian Academy of Sciences (India)

Home; Fellowship. Fellow Profile. Elected: 2007 Section: Earth & Planetary Sciences. Bajpai, Prof. Sunil Ph.D. (Panjab), FNASc. Council Service: 2016-. Date of birth: 30 September 1961. Specialization: Vertebrate Paleontology, Biostratigraphy and Paleobiogeography Address: Director, Birbal Sahni Institute of ...

Fossil mega- and microflora from the Březno Beds s.s. (Bohemian Cretaceous Basin, Coniacian)

Czech Academy of Sciences Publication Activity Database

Halamski, A. T.; Kvaček, J.; Svobodová, Marcela

2018-01-01

Roč. 253, June 2018 (2018), s. 123-138 ISSN 0034-6667 Institutional support: RVO:67985831 Keywords : fossil plant * Cretaceous * taxonomy * paleobotany * Coniacian * Czech Republic Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.817, year: 2016

Cuticle microstructure as a new tool in systematic paleontology

OpenAIRE

Waugh, David A.; Feldmann, Rodney M.

2003-01-01

Fossil decapod cuticle has received little systematic study. The purpose of the present note is to survey the cuticle architecture of eleven extant decapod crabs arrayed within ten families, and to develop a classification scheme of cuticle types suitable for describing fossil and Recent decapod cuticle morphology.

Cuticle microstructure as a new tool in systematic paleontology

NARCIS (Netherlands)

Waugh, David A.; Feldmann, Rodney M.

2003-01-01

Fossil decapod cuticle has received little systematic study. The purpose of the present note is to survey the cuticle architecture of eleven extant decapod crabs arrayed within ten families, and to develop a classification scheme of cuticle types suitable for describing fossil and Recent decapod

Rostrokonchy z devonských sedimentů moravskoslezské pánve

Czech Academy of Sciences Publication Activity Database

Weinerová, Hedvika; Weiner, Tomáš; Hladil, Jindřich

2017-01-01

Roč. 50, č. 1 (2017), s. 153-157 ISSN 0514-8057 R&D Projects: GA ČR GA14-18183S Institutional support: RVO:67985831 Keywords : Rostroconchia * Mollusca * Devonian * Moravo-Silesian Basin Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology

78 FR 77198 - Notice of Final Federal Agency Actions on Proposed Highway in California

Science.gov (United States)

2013-12-20

.... Land: Section 4(f) of the Department of Transportation Act of 1966 [49 U.S.C. 303]. 4. Paleontology...], Fish and Wildlife Coordination Act (16 U.S.C. 661-667(d)), Migratory Bird Treaty Act (16 U.S.C. 703-712...

Lanternfisches (Myctophidae) with otoliths .i.in situ./i. from the Early Oligocene of the Eastern Paratethys (western Ukraine)

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš; Schwarzhans, W.; Kovalchuk, O.

2017-01-01

Roč. 285, č. 2 (2017), s. 213-225 ISSN 0077-7749 Institutional support: RVO:67985831 Keywords : Myctophidae * Oligophus moravicus * Eomyctophum sp. * otoliths in situ * Oligocene * diversity Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 0.777, year: 2016

77 FR 55222 - Notice of Availability of the Draft Resource Management Plan Amendment and the Draft...

Science.gov (United States)

2012-09-07

... activities at least 15 days in advance through public notices, media releases, and/or mailings. ADDRESSES... considers the creation of new special designations, management of lands with wilderness characteristics, or... and paleontological resources, American Indian concerns, recreation management, social and economic...

Miocene bristlemouths (Teleostei: Stomiiformes: Gonostomatidae) from the Makrilia Formation, Ierapetra, Crete

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš; Carnevale, G.

2017-01-01

Roč. 16, č. 3 (2017), s. 266-277 ISSN 1631-0683 Institutional support: RVO:67985831 Keywords : Teleostei * Gonostomatidae * Crete * Neogene * Tortonian * Cyclothone gaudanti sp. nov. Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.376, year: 2016

.i.Asteriacites./i. and other trace fossils from the Po Formation (Visean–Serpukhovian), Ganmachidam Hill, Spiti Valley (Himalaya) and its paleoenvironmental significance

Czech Academy of Sciences Publication Activity Database

Singh, B. P.; Bhargava, O. N.; Mikuláš, Radek; Prasad, S. K.; Singla, G.; Kaur, R.

2017-01-01

Roč. 68, č. 5 (2017), s. 464-478 ISSN 1335-0552 Institutional support: RVO:67985831 Keywords : Po Formation * Visean–Serpukhovian * Spiti * trace fossils * Cruziana ichnofacies Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.358, year: 2016

Summary of papers included within this commemorative issue

Czech Academy of Sciences Publication Activity Database

Roček, Zbyněk

2016-01-01

Roč. 72, 1/2 (2016), s. 15-16 ISSN 2533-4050 Institutional support: RVO:67985831 Keywords : paleontology * summmary Subject RIV: DB - Geology ; Mineralogy http://www.nm.cz/publikace/archiv-en.php?id=4&rok=72&kcislu=1-2&f_=Show

Tempo and mode in the macroevolutionary reconstruction of Darwinism.

Science.gov (United States)

Gould, S J

1994-01-01

Among the several central meanings of Darwinism, his version of Lyellian uniformitarianism--the extrapolationist commitment to viewing causes of small-scale, observable change in modern populations as the complete source, by smooth extension through geological time, of all magnitudes and sequences in evolution--has most contributed to the causal hegemony of microevolution and the assumption that paleontology can document the contingent history of life but cannot act as a domain of novel evolutionary theory. G. G. Simpson tried to combat this view of paleontology as theoretically inert in his classic work, Tempo and Mode in Evolution (1944), with a brilliant argument that the two subjects of his title fall into a unique paleontological domain and that modes (processes and causes) can be inferred from the quantitative study of tempos (pattern). Nonetheless, Simpson did not cash out his insight to paleontology's theoretical benefit because he followed the strict doctrine of the Modern Synthesis. He studied his domain of potential theory and concluded that no actual theory could be found--and that a full account of causes could therefore be located in the microevolutionary realm after all. I argue that Simpson was unduly pessimistic and that modernism's belief in reductionistic unification (the conventional view of Western intellectuals from the 1920s to the 1950s) needs to be supplanted by a postmodernist commitment to pluralism and multiple levels of causation. Macro- and microevolution should not be viewed as opposed, but as truly complementary. I describe the two major domains where a helpful macroevolutionary theory may be sought--unsmooth causal boundaries between levels (as illustrated by punctuated equilibrium and mass extinction) and hierarchical expansion of the theory of natural selection to levels both below (gene and cell-line) and above organisms (demes, species, and clades). Problems remain in operationally defining selection at non-organismic levels

Ammonites, inoceramids and stable carbon isotopes of the Cenomanian-Turonian OAE2 interval in central Europe: Pecínov quarry, Bohemian Cretaceous Basin (Czech Republic)

Czech Academy of Sciences Publication Activity Database

Košťák, M.; Čech, S.; Uličný, David; Ekrt, B.

(2018) ISSN 0195-6671 R&D Projects: GA ČR GA17-10982S Institutional support: RVO:67985530 Keywords : Mid-European Cretaceous * OAE2 interval * paleontology * geochemistry * stratigraphic correlation Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Geology Impact factor: 2.015, year: 2016

Epistemic values in the Burgess Shale debate

DEFF Research Database (Denmark)

Baron, Christian

2009-01-01

Focusing primarily on papers and books discussing the evolutionary and systematic interpretation of the Cambrian animal fossils from the Burgess Shale fauna, this paper explores the role of epistemic values in the context of a discipline (paleontology) striving to establish scientific authority w...

Fossil .i.Comptonia difformis./i. (Sternberg) Berry (Myricaceae) from the type area in North Bohemia with comments on foliage anatomy and associated fruits

Czech Academy of Sciences Publication Activity Database

Teodoridis, V.; Kvaček, Z.; Mach, K.; Sakala, J.; Dašková, Jiřina; Rojík, P.

2017-01-01

Roč. 92, č. 2 (2017), s. 185-210 ISSN 1214-1119 Institutional support: RVO:67985831 Keywords : Comptonia * fruit * leaf * pollen * wood * morphology * ecology * Paleogene * Neogene * Bohemia * Europe Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.175, year: 2016

The main fish communities of the limnic Permian and Carboniferous basins of the Czech Republic

Czech Academy of Sciences Publication Activity Database

Zajíc, Jaroslav

33-34, - (2006), s. 99-101. ISBN 80-210-4097-1. ISSN 1211-281X. [Paleontological Conference /7./. Brno, 19.10.2006-20.10.2006] Institutional research plan: CEZ:AV0Z30130516 Keywords : ichthyofaunae * Upper Carboniferous * Lower Permian Subject RIV: EG - Zoology

75 FR 47621 - Final Environmental Impact Statement for the North Fork Rancheria's Proposed 305-Acre Trust...

Science.gov (United States)

2010-08-06

... administration space. Food and beverage facilities would include three full service restaurants, a five-tenant... resources, air quality, biological resources, cultural and paleontological resources, socioeconomic..., Cultural Resources Management and Safety, at the address listed in the ADDRESSES section of this notice, or...

From Fossils to Astrobiology Records of Life on Earth and Search for Extraterrestrial Biosignatures

CERN Document Server

Seckbach, Joseph

2008-01-01

From Fossils to Astrobiology reviews developments in paleontology and geobiology that relate to the rapidly-developing field of Astrobiology, the study of life in the Universe. Many traditional areas of scientific study, including astronomy, chemistry and planetary science, contribute to Astrobiology, but the study of the record of life on planet Earth is critical in guiding investigations in the rest of the cosmos. In this varied book, expert scientists from 15 countries present peer-reviewed, stimulating reviews of paleontological and astrobiological studies. The overviews of established and emerging techniques for studying modern and ancient microorganisms on Earth and beyond, will be valuable guides to evaluating biosignatures which could be found in the extraterrestrial surface or subsurface within the Solar System and beyond. This volume also provides discussion on the controversial reports of "nanobacteria" in the Martian meteorite ALH84001. It is a unique volume among Astrobiology monographs in focusi...

Reevaluating the age of the Walden Creek Group and the kinematic evolution of the western Blue Ridge, southern Appalachians

Science.gov (United States)

Thigpen, J. Ryan; Hatcher, Robert D.; Kah, Linda C.; Repetski, John E.

2016-01-01

An integrated synthesis of existing datasets (detailed geologic mapping, geochronologic, paleontologic, geophysical) with new paleontologic and geochemical investigations of rocks previously interpreted as part of the Neoproterozoic Walden Creek Group in southeastern Tennessee suggest a necessary reevaluation of the kinematics and structural architecture of the Blue Ridge Foothills. The western Blue Ridge of Tennessee, North Carolina, and Georgia is composed of numerous northwest-directed early and late Paleozoic thrust sheets, which record pronounced variation in stratigraphic/structural architecture and timing of metamorphism. The detailed spatial, temporal, and kinematic relationships of these rocks have remained controversial. Two fault blocks that are structurally isolated between the Great Smoky and Miller Cove-Greenbrier thrust sheets, here designated the Maggies Mill and Citico thrust sheets, contain Late Ordovician-Devonian conodonts and stable isotope chemostratigraphic signatures consistent with a mid-Paleozoic age. Geochemical and paleontological analyses of Walden Creek Group rocks northwest and southeast of these two thrust sheets, however, are more consistent with a Late Neoproterozoic (550–545 Ma) depositional age. Consequently, the structural juxtaposition of mid-Paleozoic rocks within a demonstrably Neoproterozoic-Cambrian succession between the Great Smoky and Miller Cove-Greenbrier thrust sheets suggests that a simple foreland-propagating thrust sequence model is not applicable in the Blue Ridge Foothills. We propose that these younger rocks were deposited landward of the Ocoee Supergroup, and were subsequently plucked from the Great Smoky fault footwall as a horse, and breached through the Great Smoky thrust sheet during Alleghanian emplacement of that structure.

Outstanding Science Trade Books for Children in 1989.

Science.gov (United States)

Science and Children, 1990

1990-01-01

Listed are 100 trade books with brief descriptions and availability information. Categories include animals, biography, space science and astronomy, anthropology and paleontology, life sciences, earth science, conservation, medical and health sciences, physics, technology, and engineering. Criteria for inclusion in this annual list are presented.…

Neogene Amazonia: Introduction to the special issue Journal of South American Earth Sciences, New contributions on Neogene geography and depositional environments in Amazonia

NARCIS (Netherlands)

Hoorn, C.; Vonhof, H.B.

2006-01-01

The paleontological data presented in this special issue provide a new insight into species migration and radiation in Amazonia during the Miocene. At the time, Amazonia was characterized by a very extensive, long-lived, semi-isolated, freshwater wetland ecosystem that was supplied with water and

Ancient DNA reveals past existence of Eurasian lynx in Spain

DEFF Research Database (Denmark)

Rodríguez-Varela, R.; García, N.; Nores, C.

2016-01-01

. The paleontological record and our data indicate a population replacement of the Iberian lynx by the Eurasian lynx during the Pleistocene/Holocene transition in the Cantabrian cornice of Spain. Phylogeographic patterns of Late Pleistocene and Holocene Eurasian lynx from Iberia, France, Italy and Denmark show...

75 FR 47618 - Final Environmental Impact Statement for the Proposed Enterprise Rancheria Gaming Facility and...

Science.gov (United States)

2010-08-06

... (consisting of a buffet, gourmet restaurant, and bar), meeting space, guest support services, offices, and a... resources, water resources, air quality, biological resources, cultural and paleontological resources..., Cultural Resources Management and Safety, at the BIA address above or at the telephone number provided in...

76 FR 18241 - Notice of Intent To Prepare an Environmental Impact Statement for the Proposed Energy Gateway...

Science.gov (United States)

2011-04-01

..., 5353 Yellowstone Road, Cheyenne, Wyoming 82003, Attention: Tamara Gertsch. FOR FURTHER INFORMATION... height with average spans between towers of 1,000 to 1,500 feet (4 to 5 structures per mile). Permanent... historical sites; Paleontological resources; Changes in visual quality and settings; National Scenic and...

Temperature and isotopic composition of seawater in the epicontinental sea (Central Paratethys) during the Middle Miocene Climate Transition based on Mg/Ca, δ.sup.18./sup.O and δ.sup.13./sup.C from foraminiferal tests

Czech Academy of Sciences Publication Activity Database

Scheiner, Filip; Holcová, K.; Milovský, R.; Kuhnert, H.

2018-01-01

Roč. 495, 15 April 2018 (2018), s. 60-71 ISSN 0031-0182 Institutional support: RVO:67985831 Keywords : Central Paratethys * Langhian * Mg/Ca offset * water mass hydrography * δ 18 O seawater Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 2.578, year: 2016

Sporophytes of polysporangiate land plants from the early Silurian period may have been photosynthetically autonomous

Czech Academy of Sciences Publication Activity Database

Libertín, M.; Kvaček, J.; Bek, Jiří; Žárský, V.; Štorch, Petr

2018-01-01

Roč. 4, 30 April 2018 (2018), s. 269-271 ISSN 2055-026X Institutional support: RVO:67985831 Keywords : earliest vascular plant s * in situ spores * Silurian * polysporangiate plant s Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 10.300, year: 2016

The Holocene in the coastal zone of Uruguay

International Nuclear Information System (INIS)

Garcia Rodriguez, F.

2011-07-01

This book represents a compilation of several scientific Holocene paleoenvironmental aspects of the coastal zone in Uruguay. It includes information about geological, geomorphological, evolutionary genetics, paleontological, paleobotanic, paleoclimatological, paleolimnological, paleoceanographic and archeologic aspects. The chapters presented were arbitrated by national and foreign recognized scientists

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Author Affiliations. K Verma1 S K Bharti1 2 A D Singh1. Center of Advanced Study in Geology, Banaras Hindu University, Varanasi 221 005, India. Paleontology Div. I CHQ, Geological Survey of India, 15 A & B Kyd Street, Kolkata 700 016, India.

77 FR 2999 - Notice of Availability of the Draft Environmental Impact Statement and Notice of Segregation for...

Science.gov (United States)

2012-01-20

... resources, human health, and hazardous materials, lands and realty, noise, noxious weeds, paleontological... Resource Management Plan. The proposed wind turbines would be up to 262-feet-tall from the ground to the... substations, an electrical interconnection facility/switchyard owned and operated by Western Area Power...

Lower Devonian Brachiopods and Stratigraphy of North Palencia (Cantabrian Mountains, Spain)

NARCIS (Netherlands)

Binnekamp, J.G.

1965-01-01

A continuous sequence of Devonian sediments is exposed in the northern part of the province of Palencia (NW-Spain), on the southern slope of the Cantabrian Mountains. This study concerns the stratigraphy and paleontology of the Lower Devonian formations. At the base of the sequence a clastic

Water bird fauna in the Carpathian Basin from the beginnings through historical times

OpenAIRE

Kessler Jenő (Eugen)

2017-01-01

This study aims to summarize the knowledge about the evolution and fossil remains of avian fauna near waterbodies, since ornithologists, who rarely come across or research the paleontology of birds, do not possess significantly detailed knowledge about the evolution and evidence of the current avian fauna.

Křídové uhelnaté jílovce u Vojnova Městce na Českomoravské vrchovině

Czech Academy of Sciences Publication Activity Database

Juráček, J.; Kvaček, J.; Malý, K.; Svobodová, Marcela

2016-01-01

Roč. 19, č. 1 (2016), s. 7-14 E-ISSN 2336-7113 Institutional support: RVO:67985831 Keywords : coal claystones * Bohemian Cretaceous Basin * Eastern Bohemia * mining * paleontology * stratigraphy * sedimentary environment Subject RIV: DB - Geology ; Mineralogy http://actarerumnaturalium.cz/wp-content/uploads/2016/09/ARN_2016__2.pdf

Bericht 2005 über fazielle und biostratigraphishe Untersuchungen in der Gosau der Neualm bei Russbach am Pass Gschütt auf Blatt 95 St. Wolfgang

Czech Academy of Sciences Publication Activity Database

Hradecká, L.; Lobitzer, H.; Svobodová, Marcela; Švábenická, L.

2006-01-01

Roč. 146, 1-2 (2006), s. 132-133 ISSN 0016-7800 Institutional research plan: CEZ:AV0Z30130516 Keywords : sedimentology * paleontology * Gosau Fm., * Northern Calcareous Alps, * Austria Subject RIV: DB - Geology ; Mineralogy http://www.geologie.ac.at/filestore/download/JB1461_132_A.pdf

Life: Here? There? Elsewhere? The Search for Life on Venus and Mars. Life in the Universe Series.

Science.gov (United States)

1996

This classroom kit, designed by curriculum developers working with teachers and scientists from the SETI (Search for Extraterrestrial Intelligence) Institute, helps teachers guide students in the exploration of life through the multidisciplinary sciences of paleontology and exobiology. It reflects the real-life methods of science: making…

Pseudothurmanniid ammonites from quarries near Lietavská Lúčka and their stratigraphical significance (Late Hauterivian,\

Czech Academy of Sciences Publication Activity Database

Vašíček, Zdeněk; Málek, O.

2017-01-01

Roč. 61, č. 3 (2017), s. 613-631 ISSN 1641-7291 Institutional support: RVO:68145535 Keywords : ammonites * taxonomy * stratigraphy * Hauterivian * Western Carpathians Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.129, year: 2016 https://gq.pgi.gov.pl/article/view/25630/pdf

Bajpai, Prof. Sunil

Indian Academy of Sciences (India)

... Paleontology, Biostratigraphy and Paleobiogeography Address: Director, Birbal Sahni Institute of Palaeobotany, 53, University Road, Lucknow 226 007, U.P.. Contact: Office: (0522) 274 0470, (0522) 274 0439. Fax: (0522) 274 0485. Email: directorbsip@gmail.com, director@bsip.res.in. YouTube · Twitter · Facebook ...

Notes on development of the Oligocene trachinid .i.Trachinus minutus./i. (Jonet, 1958)

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš

2017-01-01

Roč. 308, 1-3 (2017), s. 69-87 ISSN 0375-0442 R&D Projects: GA ČR(CZ) GP13-19250P Institutional support: RVO:67985831 Keywords : Teleostei * osteology * ontogeny * Oligocene * Europe Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.615, year: 2016

75 FR 14623 - Notice of Availability of the Draft Imperial Sand Dunes Recreation Area Management Plan and Draft...

Science.gov (United States)

2010-03-26

...; transportation and public access; wildlife and botany; cultural resources and paleontology; renewable energy... by Interstate 8 and the California/Mexico border. The primary activities in the ISDRA include off.... Limitations on use of public lands within the Plank Road ACEC include restrictions on wind and solar energy...

Introduction

Czech Academy of Sciences Publication Activity Database

Roček, Zbyněk

2016-01-01

Roč. 72, 1/2 (2016), s. 3-4 ISSN 2533-4050 Institutional support: RVO:67985831 Keywords : paleontology * Zdeněk Špinar, palaeontologist Subject RIV: DB - Geology ; Mineralogy http://www.nm.cz/publikace/archiv-en.php?id=4&rok=72&kcislu=1-2&f_=Show

Incorporating Informal Learning Environments and Local Fossil Specimens in Earth Science Classrooms: A Recipe for Success

Science.gov (United States)

Clary, Renee M.; Wandersee, James H.

2009-01-01

In an online graduate paleontology course taken by practicing Earth Science teachers, we designed an investigation using teachers' local informal educational environments. Teachers (N = 28) were responsible for photographing, describing, and integrating fossil specimens from two informal sites into a paleoenvironmental analysis of the landscape in…

Deciphering Equine Evolution and Spatial Ancestry with Ancient Data

DEFF Research Database (Denmark)

Jónsson, Hákon

High-throughput sequencing has opened ancient DNA research to genomics, revolutionizing the amount of genetic information retrievable from archaeological and paleontological remains. Paleogenomics is still in infancy and requires substantial improvements in computational methods tailored to the s......High-throughput sequencing has opened ancient DNA research to genomics, revolutionizing the amount of genetic information retrievable from archaeological and paleontological remains. Paleogenomics is still in infancy and requires substantial improvements in computational methods tailored...... in the analysis of environmental bacterial sequences, which generally dominate ancient DNA extracts, and in the first pipeline completely devoted to the computational analysis of raw ancient DNA sequences. We then develop a spatially explicit method for determining which extant populations show the greatest...... genetic anity to ancient individuals, which often represents the key question in human paleogenomic projects. We applied the computational infrastructure developed to complete the genomic characterization of extant members of the genus Equus, which is composed of horses, asses and zebras. We sequenced...

Paleozoic in situ spores and pollen. Lycopsida

Czech Academy of Sciences Publication Activity Database

Bek, Jiří

2017-01-01

Roč. 296, 1/6 (2017), s. 1-111 ISSN 0375-0299 R&D Projects: GA ČR GAP210/12/2053 Institutional support: RVO:67985831 Keywords : in situ spores * reproductive organs * Lycopsida * Paleozoic Sub ject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.333, year: 2016

Water bird fauna in the Carpathian Basin from the beginnings through historical times

Directory of Open Access Journals (Sweden)

Kessler Jenő (Eugen

2017-06-01

Full Text Available This study aims to summarize the knowledge about the evolution and fossil remains of avian fauna near waterbodies, since ornithologists, who rarely come across or research the paleontology of birds, do not possess significantly detailed knowledge about the evolution and evidence of the current avian fauna.

Gaps in the Rock and Fossil Records and Implications for the Rate and Mode of Evolution.

Science.gov (United States)

Smith, Grant Sackett

1988-01-01

Examines three types of gaps in the fossil record: real gaps, imaginary gaps, and temporary gaps. Reviews some recent evidence concerning evolution from the paleontological record of microfossils, invertebrates, and vertebrates in order to make some general conclusions regarding the manner in which life evolved on earth. (CW)

Revision of .i.Dendraena pinnatilobata./i. Němejc from the Pennsylvanian of the Czech Republic

Czech Academy of Sciences Publication Activity Database

Frojdová, Jana; Pšenička, J.; Bek, Jiří; Martínek, K.

2017-01-01

Roč. 92, č. 1 (2017), s. 75-94 ISSN 1214-1119 R&D Projects: GA ČR GAP210/12/2053 Institutional support: RVO:67985831 Keywords : Anachoropteris * Dendraena * fern * in situ spores * Pennsylvanian Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.175, year: 2016

Savčí společenstvo posledního glaciálu z jeskyně Barové - nové poznatky

Czech Academy of Sciences Publication Activity Database

Roblíčková, M.; Káňa, V.; Nývltová Fišáková, Miriam

2017-01-01

Roč. 102, 1-2 (2017), s. 119-142 ISSN 1211-8796 Institutional support: RVO:68081758 Keywords : Quaternary palaeontology * Late Pleistocene * Moravian Karst * Barová Cave * animal assemblage * Ursus ex gr. spelaeus * wintering site * gnawing marks * hunting and scavenging activity * seasonality Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology

Sea-level changes vs. organic productivity as controls on Early and Middle Devonian bioevents: Facies- and gamma-ray based sequence-stratigraphic correlation of the Prague Basin, Czech Republic

Czech Academy of Sciences Publication Activity Database

Bábek, O.; Faměra, M.; Šimíček, D.; Weinerová, H.; Hladil, Jindřich; Kalvoda, J.

2018-01-01

Roč. 160, January (2018), s. 75-95 ISSN 0921-8181 R&D Projects: GA ČR GA14-18183S Institutional support: RVO:67985831 Keywords : Devonian * carbonates * sequence stratigraphy * bioevents * eustatic cyclicity * palaeoclimatology Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 3.915, year: 2016

Managing climate change refugia for climate adaptation

Science.gov (United States)

Toni Lyn Morelli; Christopher Daly; Solomon Z. Dobrowski; Deanna M. Dulen; Joseph L. Ebersole; Stephen T. Jackson; Jessica D. Lundquist; Connie Millar; Sean P. Maher; William B. Monahan; Koren R. Nydick; Kelly T. Redmond; Sarah C. Sawyer; Sarah Stock; Steven R. Beissinger

2016-01-01

Refugia have long been studied from paleontological and biogeographical perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change refugia, here defined as areas relatively buffered from contemporary climate change over time that...

An Oligocene toadfish (Teleostei, Percomorpha) from Moravia, Czech Republic: The earliest skeletal record for the order Batrachoidiformes

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš; Carnevale, G.

2017-01-01

Roč. 92, č. 1 (2017), s. 123-131 ISSN 1214-1119 R&D Projects: GA ČR(CZ) GA16-21523S Institutional support: RVO:67985831 Keywords : Teleostei * Batrachoidiformes * Oligocene * Menilitic Formation * Paratethys Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.175, year: 2016

Paleontología y ambientes sedimentarios del Triásico medio, Muschelkalk, de la Cordillera Ibérica 1: Cuencas y Valencia. España

Directory of Open Access Journals (Sweden)

López Gómez, J.

1989-12-01

Full Text Available The Muscbelkalk Facies of tbe SE. Iberian Ranges is formed by tbe Landete Dolomites (d.L., Mas Sandstones, Marls and Gypsum (a.m.y.M and Cañete Dolomites and Limestone (d.c.C. Formations. This paper deals on tbe paleontology and sedimentary environments of the two carbonatic Formations (d.L. and d.c.C.. Ten sections all over the area have been studied in detail and nine facies associations, each one formed by sequences less than 2m. thick, have been differenciated. Possibly, due to the dolomitization, fossil register is in general considered to be scaree and badly preserved. The analysis of the sequences reveals three different subenvironments (shoal, lagoon and sabkha. Two episodes can be differenciated for each carbonatic formation during the development of the depositional system: first, a short-lived transgression fol1owed by a longer regresive period. By far, the most abundant fossils are Molluscs of Bivalvia Class, forming a benthonic association dominated by suspensivores. The bivalves are found in both carbonated units, although in the upper one the faunistic richness and specific diversity are higher.The taphonomic analysis reveals some autochtonous associations in both formations. The bivalve association found at the last beds of the upper Muschelkalk Facies of the lberian Ranges is known as tbe «Teruel Fauna», well represented in the Villora and Henarejos sections. The association consists on endo and epibisate Bivalves and some cemented ones, and represents different shallow carbonatic marine subenvironments. A Section Type has been cboosen and divided into 4 and 5 main levels or parts (for d.L. and d.c.C. respectively. Each of these parts is dominated by the abundance of one of the facies associations.Las unidades dolomías de Landete (d. L., areniscas, margas y yesos del Mas (a.m.y.M. y dolomías y calizas de Cañete (d.c.C. (Anisiense-parte inferior del Camiense, Triásico mediosuperior de base a techo respectivamente

Human influence on distribution and extinctions of the late Pleistocene Eurasian megafauna.

Science.gov (United States)

Pushkina, Diana; Raia, Pasquale

2008-06-01

Late Pleistocene extinctions are of interest to paleontological and anthropological research. In North America and Australia, human occupation occurred during a short period of time and overexploitation may have led to the extinction of mammalian megafauna. In northern Eurasia megafaunal extinctions are believed to have occurred over a relatively longer period of time, perhaps as a result of changing environmental conditions, but the picture is much less clear. To consider megafaunal extinction in Eurasia, we compare differences in the geographical distribution and commonness of extinct and extant species between paleontological and archaeological localities from the late middle Pleistocene to Holocene. Purely paleontological localities, as well as most extinct species, were distributed north of archaeological sites and of the extant species, suggesting that apart from possible differences in adaptations between humans and other species, humans could also have a detrimental effect on large mammal distribution. However, evidence for human overexploitation applies only to the extinct steppe bison Bison priscus. Other human-preferred species survive into the Holocene, including Rangifer tarandus, Equus ferus, Capreolus capreolus, Cervus elaphus, Equus hemionus, Saiga tatarica, and Sus scrofa. Mammuthus primigenius and Megaloceros giganteus were rare in archaeological sites. Carnivores appear little influenced by human presence, although they become rarer in Holocene archaeological sites. Overall, the data are consistent with the conclusion that humans acted as efficient hunters selecting for the most abundant species. Our study supports the idea that the late Pleistocene extinctions were environmentally driven by climatic changes that triggered habitat fragmentation, species range reduction, and population decrease, after which human interference either by direct hunting or via indirect activities probably became critical.

EARTH’S ROTATIONAL DECELERATION: DETERMINATION OF TIDAL FRICTION INDEPENDENT OF TIMESCALES

International Nuclear Information System (INIS)

Deines, Steven D.; Williams, Carol A.

2016-01-01

This paper determines Earth's rotational deceleration without relying on atomic or ephemeris timescales. Earth's rotation defines the civil time standard called Universal Time (UT). Our previous paper did not examine tidal friction in depth when analyzing the timescale divergence between UT and International Atomic Time (TAI). We examine all available paleontological fossils and deposits for the direct measurements of Earth's past rotation rates, because that record includes all contributing effects. We examine paleontological reports that date Earth's rotation rate using corals, bivalves, brachiopods, rhythmites, and stromatolites. Contributions that vary Earth's moment of inertia, such as continental plate drifts, coastline changes, ice age formations, and viscous glacial rebounds, are superimposed with the secular deceleration. The average deceleration of Earth's rotation rate from all available fossil data is found to be (5.969 ± 1.762) × 10 −7 rad yr −2 . Our value is 99.8% of the total rotational deceleration determined by Christodoulidis et al., who used artificial satellite data, and our value is 96.6% of the expected tidal friction value obtained by Stephenson and Morrison. Taking the derivative of conserved angular momentum, the predicted lunar orbital deceleration caused by the average rotational deceleration corresponds closely to lunar models. When evaluating the significant time gaps between UT and TAI, Earth's rotational deceleration is a minor contributing factor. Also, the secular deceleration rate is necessary to correctly date ancient astronomical events. We strongly encourage that more ocean paleontological evidence be found to supplement the record to separate the many periodic variations embedded in these data

EARTH’S ROTATIONAL DECELERATION: DETERMINATION OF TIDAL FRICTION INDEPENDENT OF TIMESCALES

Energy Technology Data Exchange (ETDEWEB)

Deines, Steven D. [Donatech Corporation, Fairfield, IA 52556 (United States); Williams, Carol A., E-mail: steven.deines@gmail.com, E-mail: cw@math.usf.edu [Department of Mathematics and Statistics (Prof. emeritus), University of South Florida, 4202 E. Fowler Ave., Tampa, FL 33620 (United States)

2016-04-15

This paper determines Earth's rotational deceleration without relying on atomic or ephemeris timescales. Earth's rotation defines the civil time standard called Universal Time (UT). Our previous paper did not examine tidal friction in depth when analyzing the timescale divergence between UT and International Atomic Time (TAI). We examine all available paleontological fossils and deposits for the direct measurements of Earth's past rotation rates, because that record includes all contributing effects. We examine paleontological reports that date Earth's rotation rate using corals, bivalves, brachiopods, rhythmites, and stromatolites. Contributions that vary Earth's moment of inertia, such as continental plate drifts, coastline changes, ice age formations, and viscous glacial rebounds, are superimposed with the secular deceleration. The average deceleration of Earth's rotation rate from all available fossil data is found to be (5.969 ± 1.762) × 10{sup −7} rad yr{sup −2}. Our value is 99.8% of the total rotational deceleration determined by Christodoulidis et al., who used artificial satellite data, and our value is 96.6% of the expected tidal friction value obtained by Stephenson and Morrison. Taking the derivative of conserved angular momentum, the predicted lunar orbital deceleration caused by the average rotational deceleration corresponds closely to lunar models. When evaluating the significant time gaps between UT and TAI, Earth's rotational deceleration is a minor contributing factor. Also, the secular deceleration rate is necessary to correctly date ancient astronomical events. We strongly encourage that more ocean paleontological evidence be found to supplement the record to separate the many periodic variations embedded in these data.

Ontogenetic Shape Change in the Chicken Brain: Implications for Paleontology

OpenAIRE

Kawabe, Soichiro; Matsuda, Seiji; Tsunekawa, Naoki; Endo, Hideki

2015-01-01

Paleontologists have investigated brain morphology of extinct birds with little information on post-hatching changes in avian brain morphology. Without the knowledge of ontogenesis, assessing brain morphology in fossil taxa could lead to misinterpretation of the phylogeny or neurosensory development of extinct species. Hence, it is imperative to determine how avian brain morphology changes during post-hatching growth. In this study, chicken brain shape was compared at various developmental st...

Quaternary continental deposits in north of Uruguay: stratigraphy and paleontology

International Nuclear Information System (INIS)

Goso Aguilar, C.; Ubilla, M.

2004-01-01

Conglomeradic and sandstones lithofacies corresponding to fluvial and alluvial environments were recognized. These sediments partially belong to the quaternary Mataojos Formation. A discordant contact with the upper pelitic deposits identified with the Sopas Formation was detected. This paper deals with sedimentological and stratigraphical considerations in order to explain the sedimentary processes during the genesis of these stratigraphic sections as well as to begin a lithostratigraphical discussion about the operability of those units. In turn, chronologic and paleoenvironment comments are provided taken into account vertebrates fossils and tools to perform chronocorrelation with southern sedimentological units of Uruguay [es

A Field-Based Biomimicry Exercise Helps Students Discover Connections among Biodiversity, Form and Function, and Species Conservation during Earth's Sixth Extinction

Science.gov (United States)

Soja, Constance M.

2014-01-01

In a first-year seminar on mass extinctions, a field-based, paleontology-focused exercise promotes active learning about Earth's biodiversity, form and function, and the biomimicry potential of ancient and modern life. Students study Devonian fossils at a local quarry and gain foundational experience in describing anatomy and relating form to…

Revision of the Pennsylvanian fern .i.Boweria./i. Kidston and the establishment of the new genus .i.Kidstoniopteris./i.

Czech Academy of Sciences Publication Activity Database

Frojdová, Jana; Pšenička, J.; Bek, Jiří; Cleal, Ch. J.

2017-01-01

Roč. 236, January (2017), s. 33-58 ISSN 0034-6667 R&D Projects: GA ČR(CZ) GAP210/12/2053 Institutional support: RVO:67985831 Keywords : Boweria * Kidstoniopteris * fern * Pennsylvanian * in situ spores * taxonomy * cuticles Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.817, year: 2016

Všechno už tu bylo. Jenom trochu menší.

Czech Academy of Sciences Publication Activity Database

Mikuláš, Radek

2016-01-01

Roč. 95, č. 3 (2016), s. 154-157 ISSN 0042-4544 Institutional support: RVO:67985831 Keywords : geology * geological history of the Earth * historical geology * geological eras * Anthropocene * paleontology * ichnology * fossils * trace fossils * fossil animals * sediments Subject RIV: DB - Geology ; Mineralogy http://casopis.vesmir.cz/clanek/vsechno-uz-tu-bylo

The Case for "Big History."

Science.gov (United States)

Christian, David

1991-01-01

Urges an approach to the teaching of history that takes the largest possible perspective, crossing time as well as space. Discusses the problems and advantages of such an approach. Describes a course on "big" history that begins with time, creation myths, and astronomy, and moves on to paleontology and evolution. (DK)

Some perisphinctoid ammonites of the Štramberk Limestone and their dating with associated microfossils (Tithonian to Lower Berriasian, Outer Western Carpathians, Czech Republic)

Czech Academy of Sciences Publication Activity Database

Vašíček, Zdeněk; Reháková, D.; Skupien, P.

2017-01-01

Roč. 68, č. 6 (2017), s. 583-605 ISSN 1335-0552 Institutional support: RVO:68145535 Keywords : Ammonoidea * Calpionellids * calcareous dinoflagellates * Upper Jurassic * Western Carpathians Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.358, year: 2016 http://www.geologicacarpathica.com/browse-journal/volumes/68-6/article-860/

Fossil Explorers

Science.gov (United States)

Moran, Sean; McLaughlin, Cheryl; MacFadden, Bruce; Jacobbe, Elizabeth; Poole, Michael

2015-01-01

Many young learners are fascinated with fossils, particularly charismatic forms such as dinosaurs and giant sharks. Fossils provide tangible, objective evidence of life that lived millions of years ago. They also provide a timescale of evolution not typically appreciated by young learners. Fossils and the science of paleontology can, therefore,…

Anthropometrical Profiles Of The Frontal Sinus In Population Of ...

African Journals Online (AJOL)

The anthropometrical profiles, function and variation of frontal sinus have been poorly understood. Understanding these are important in sinus operation and in paleontology, to understand the puzzle of the meaning of the supra orbital development. In the present study radiographs of 74 males and 46 females of south east ...

†.i.Gonostoma dracula./i. sp. nov. (Teleostei, Gonostomatidae) from the Oligocene deposits of the Central Paratethys (Romania): earliest occurrence of the modern bristlemouths

Czech Academy of Sciences Publication Activity Database

Grădianu, I.; Přikryl, Tomáš; Gregorová, R.; Harold, A. S.

2017-01-01

Roč. 92, č. 3 (2017), s. 323-336 ISSN 1214-1119 R&D Projects: GA ČR(CZ) GA16-21523S Institutional support: RVO:67985831 Keywords : Stomiiformes * Gonostomatidae * †Gonostoma dracula sp. nov. * Paratethys * Oligocene * Romania Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.175, year: 2016

Biomechanical aspects of bone microstructure in vertebrates

Indian Academy of Sciences (India)

2009-10-29

Oct 29, 2009 ... Biomechanical or biophysical principles can be applied to study biological structures in their modern or fossil form. Bone is an important tissue in paleontological studies as it is a commonly preserved element in most fossil vertebrates, and can often allow its microstructures such as lacuna and canaliculi to ...

Burrows of mayflies (Ephemeroptera) in fresh water ecosystems – general comments and examples from recent rivers of the Czech Republic and Poland

Czech Academy of Sciences Publication Activity Database

Uchman, A.; Mikuláš, Radek; Stachacz, M.

2018-01-01

Roč. 52, March 2018 (2018), s. 191-192 ISSN 0078-8554. [International Conference of Continental Ichnology /2./. 01.10.2017-08.10.2017, Nuy Walley, Western Cape] Institutional support: RVO:67985831 Keywords : ichnofossils * mayflies * Eohemeroptera Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology http://wiredspace.wits.ac.za/handle/10539/24150

Coalfields west half Cumberland County, Nova Scotia

Energy Technology Data Exchange (ETDEWEB)

Copeland, M J

1958-01-01

A geologic survey of the coal fields of the western half of Cumberland County, Nova Scotia was performed including studies of the structural geology, stratigraphy, and paleontology of the area. One part of this survey included a spectrographic analysis of 55 coals for 23 elements. These analyses are presented in tabular form.

Creating Deep Time Diaries: An English/Earth Science Unit for Middle School Students

Science.gov (United States)

Jordan, Vicky; Barnes, Mark

2006-01-01

Students love a good story. That is why incorporating literary fiction that parallels teaching goals and standards can be effective. In the interdisciplinary, thematic six-week unit described in this article, the authors use the fictional book "The Deep Time Diaries," by Gary Raham, to explore topics in paleontology, Earth science, and creative…

Short notes and reviews Insect history

NARCIS (Netherlands)

Schram, Frederick R.

2003-01-01

Review of: History of Insects, edited by A. P. Rasnitsyn and D. L. J. Quicke. Kluwer Academic Publ., Dordrecht, Netherlands, 2002, 517 pp., ISBN 14 0200 026 X In the winter of 1977, I visited the Paleontological Institute of the Academy of Sciences in Moscow. I wanted to study the type specimens of

Dinosaur Impressions

Science.gov (United States)

Taquet, Philippe

1998-09-01

Perhaps you are a paleontologist or have always wondered what it is like to be one. Or you are fascinated by fossils and like to read about the origins and natural history of dinosaurs. Or maybe you are an avid traveler and reader of travelogues. If you are any of these things, then this book is for you. Originally published in 1994 in French, Dinosaur Impressions is the engaging account of thirty years of travel and paleontological exploration by Philippe Taquet, one of the world's most noted paleontologists. Dr. Taquet takes the reader on a surprisingly far-flung tour ranging from the Provence countryside to the Niger desert, from the Brazilian bush to the Mongolian Steppes, and from the Laos jungle to the Moroccan mountains in search of dinosaur bones and what they have to tell us about a vanished world. With wry humor and lively anecdotes, Dr. Taquet retraces the history of paleontological research, along the way discussing the latest theories of dinosaur existence and extinction. Elegantly translated by Kevin Padian, Dinosaur Impressions provides a unique, thoughtful perspective not often encountered in American- and English-language works. This insightful, first-hand account of an exceptional career is also a travelogue par excellence that will enthrall enthusiasts and general readers alike. Philippe Taquet is the Director of the National Museum of Natural History in Paris and is a member of the French Academy of Sciences. Kevin Padian is a professor in the Department of Integrative Biology and Curator of the Museum of Paleontology at the University of California, Berkeley. He is also the editor of The Beginning of the Age of Dinosaurs (Cambridge, 1986) and The Encyclopedia of Dinosaurs (1997).

A 25 million year macrofloral record (Carboniferous-Permian) in the Czech part of the Intra-Sudetic Basin, biostratigraphy, plant diversity and vegetation patterns

Czech Academy of Sciences Publication Activity Database

Opluštil, S.; Šimůnek, Z.; Pšenička, J.; Bek, Jiří; Libertín, M.

2017-01-01

Roč. 244, SEP 2017 (2017), s. 241-307 ISSN 0034-6667 R&D Projects: GA ČR GAP210/12/2053 Institutional support: RVO:67985831 Keywords : Early Permian * floral zonation * Intra-Sudetic Basin * Pennsylvanian * plant diversity * plant taphonomy * vegetation patterns Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.817, year: 2016

Publication List - New York State Museum.

Science.gov (United States)

New York State Museum, Albany.

Presented is a list of publications in six areas: (1) Anthropology and Archeology, (2) Botany, (3) Entomology, (4) Zoology, (5) Geology and Paleontology, and (6) Miscellaneous. This list was produced by the New York State Department of Education in cooperation with the New York State Museum. The list includes the publication number, author(s),…

78 FR 4197 - Sentencing Guidelines for United States Courts

Science.gov (United States)

2013-01-18

... calculating the tax loss in a tax case, may subtract the unclaimed deductions that the defendant legitimately... are referenced to both Sec. Sec. 2B1.1 and 2B1.5 (Theft of, Damage to, or Destruction of, Cultural... Receipt of Cultural Heritage Resources or Paleontological Resources). For each of these existing statutes...

Fulltext PDF

Indian Academy of Sciences (India)

Unknown

After a doctorate in Paleontology (1967) at Columbia University, S J Gould went to Harvard where he spent the rest of his career, becoming the Alexander Agassiz Professor of Zoology in 1982. As a paleontologist, he was a specialist of gastropod molluscs from West Indies. But he soon became involved in broader and ...

Museus e a Divulgação Científica no Campo da Paleontologia

Directory of Open Access Journals (Sweden)

Alexander Wilhelm Armin Kellner

2005-12-01

Full Text Available Museums are generally regarded as having high potential for science communication. In Brazil, however, those institutions are still far away from accomplishing this mission, particularly regarding paleontology. Here we discuss several aspects regarding science communication and museums. The three main activities associated to museums are research, repositories of collections and exhibitions. The collections of the Brazilian museums and the exhibits tend to be poor when compared with similar European and North American institutions, causing a distance between museum and society. Among the attempts of changing this picture, the Museu Nacional/UFRJ, in collaboration with the Museu de Ciência da Terra (DNPM, has organized in 1999 the temporary exhibition THE TIME OF THE DINOSAURS, which turned out to be the most visited exposition regarding fossils organized in the country so far. Among the several benefits of this exhibit was to increase the interest of the population regarding paleontology. This experience has shown that the museum must interact more strongly with the society in order to fully develop its potential of science communication.

New insights on .i.Paludotona./i., an insular endemic lagomorph (Mammalia) from the Tusco-Sardinian Palaeoprovince (Italy, Turolian, Late Miocene)

Czech Academy of Sciences Publication Activity Database

Angelone, Ch.; Čermák, Stanislav; Rook, L.

2017-01-01

Roč. 123, č. 3 (2017), s. 455-473 ISSN 0035-6883 Institutional support: RVO:67985831 Keywords : Paludotona minor n. sp. * Paludotona etruria * taxonomy * evolution * insular endemism * palaeobiogeography * MN11–12 Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 0.851, year: 2016 https://riviste.unimi.it/index.php/RIPS/article/view/9082

Stratigraphically significant conodonts from the Lochkovian of the Požáry section (Barrandian area, Czechia)

Czech Academy of Sciences Publication Activity Database

Slavík, Ladislav; Carls, P.; Valenzuela-Ríos, J. I.

2003-2004, 33-34 (2006), s. 81-82. ISBN 80-210-4097-1. ISSN 1211-281X. [Paleontological Conference /7./. Brno, 19.10.2006-20.10.2006] R&D Projects: GA AV ČR(CZ) KJB300130613 Institutional research plan: CEZ:AV0Z30130516 Keywords : Lochkovian * Conodonts * Barrandian * Požáry section * biostratigraphy Subject RIV: EG - Zoology

Abstracts

International Nuclear Information System (INIS)

2001-01-01

The minutes of the Latinamerican Geology Meeting and the 3. Uruguayan Meeting organized by the National Direction of Mining and Geology (DINAMIGE) and Uruguayan Geology Society (Uruguay) includes topics such as: paleontology, sedimentation, stratigraphy, fossils, paleoclimatology, geo tectonics, coal deposits, minerals res sources, tectonic evolution of the Andes Mountain Ranges, IGCP Project, Environmental geology, Hydrogeology, fuels, and geomorphology

DNA, intelligent design and misleading metaphors

CERN Multimedia

Seely, Mark R

2003-01-01

"..the recent fruits of scientific pursuits in areas as diverse as particle physics, paleontology, and neuroscience, has led to an enhanced recognition of the complex order of the natural world. In fact, the organization that is being revealed is so intricate that a few scientists are beginning to believe that it is, well, just not natural" (2 pages).

Geologic youth of galapagos islands confirmed by marine stratigraphy and paleontology.

Science.gov (United States)

Hickman, C S; Lipps, J H

1985-03-29

Six distinctive types of fossiliferous marine deposits occur on the Galádpagos Islands that provide evidence for the age of emergence of the islands above sea level and hence a maximum age for the islands' terrestrial biota. These subtidal to supratidal deposits include (i) volcanic tuffs with fossils, (ii) limestones and sandstones interbedded with basalt, (iii) terrace deposits, (iv) beach rock, (v) supratidal talus deposits, and (vi) recently uplifted tidal and subtidal rocks and sand. With the exception of (vi), the deposits were previously assigned ages varying from Miocene to Pleistocene, but all are less than about 2 million years old. This age, together with independently determined geologic ages, indicate that the islands emerged from the sea relatively recently and that all evolution of the islands' unique terrestrial biota occurred within the past 3 to 4 million years.

Non-invasive imaging methods applied to neo- and paleontological cephalopod research

Science.gov (United States)

Hoffmann, R.; Schultz, J. A.; Schellhorn, R.; Rybacki, E.; Keupp, H.; Gerden, S. R.; Lemanis, R.; Zachow, S.

2013-11-01

Several non-invasive methods are common practice in natural sciences today. Here we present how they can be applied and contribute to current topics in cephalopod (paleo-) biology. Different methods will be compared in terms of time necessary to acquire the data, amount of data, accuracy/resolution, minimum-maximum size of objects that can be studied, of the degree of post-processing needed and availability. Main application of the methods is seen in morphometry and volumetry of cephalopod shells in order to improve our understanding of diversity and disparity, functional morphology and biology of extinct and extant cephalopods.

Organogenesis in deep time: A problem in genomics, development, and paleontology.

Science.gov (United States)

Pieretti, Joyce; Gehrke, Andrew R; Schneider, Igor; Adachi, Noritaka; Nakamura, Tetsuya; Shubin, Neil H

2015-04-21

The fossil record is a unique repository of information on major morphological transitions. Increasingly, developmental, embryological, and functional genomic approaches have also conspired to reveal evolutionary trajectory of phenotypic shifts. Here, we use the vertebrate appendage to demonstrate how these disciplines can mutually reinforce each other to facilitate the generation and testing of hypotheses of morphological evolution. We discuss classical theories on the origins of paired fins, recent data on regulatory modulations of fish fins and tetrapod limbs, and case studies exploring the mechanisms of digit loss in tetrapods. We envision an era of research in which the deep history of morphological evolution can be revealed by integrating fossils of transitional forms with direct experimentation in the laboratory via genome manipulation, thereby shedding light on the relationship between genes, developmental processes, and the evolving phenotype.

Geomagnetic reversal in brunhes normal polarity epoch.

Science.gov (United States)

Smith, J D; Foster, J H

1969-02-07

The magnetic stratigraphly of seven cores of deep-sea sediment established the existence of a short interval of reversed polarity in the upper part of the Brunches epoch of normal polarity. The reversed zone in the cores correlates well with paleontological boundaries and is named the Blake event. Its boundaries are estimated to be 108,000 and 114,000 years ago +/- 10 percent.

X-ray micro-CT and neutron CT as complementary imaging tools for non-destructive 3D imaging of rare silicified fossil plants

Czech Academy of Sciences Publication Activity Database

Karch, J.; Dudák, J.; Žemlička, J.; Vavřík, Daniel; Kumpová, Ivana; Kvaček, J.; Heřmanová, Z.; Šoltés, J.; Viererbl, L.; Morgano, M.; Kaestner, A.; Trtík, P.

2017-01-01

Roč. 12, December (2017), č. článku C12004. ISSN 1748-0221 R&D Projects: GA MŠk(CZ) LO1219 Keywords : inspection with neutrons * X-ray detectors * X ray radiography Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.220, year: 2016 http://iopscience.iop.org/article/10.1088/1748-0221/12/12/C12004/pdf

Old world monkeys

National Research Council Canada - National Science Library

Whitehead, Paul F; Jolly, Clifford J

2000-01-01

... and conservation. It will be the definitive reference on this group for professionals and graduate students in primatology, animal behavior, paleontology, morphology, systematics and physical anthropology, plus it will also be useful to senior undergraduates.  .  is Acting Collections Manager in the Division of Vertebrate Zoology at th...

The Frasnian-Famennian mass killing event(s), methods of identification and evaluation

Science.gov (United States)

Geldsetzer, H. H. J.

1988-01-01

The absence of an abnormally high number of earlier Devonian taxa from Famennian sediments was repeatedly documented and can hardly be questioned. Primary recognition of the event(s) was based on paleontological data, especially common macrofossils. Most paleontologists place the disappearance of these common forms at the gigas/triangularis contact and this boundary was recently proposed as the Frasnian-Famennian (F-F) boundary. Not unexpectedly, alternate F-F positions were suggested caused by temporary Frasnian survivors or sudden post-event radiations of new forms. Secondary supporting evidence for mass killing event(s) is supplied by trace element and stable isotope geochemistry but not with the same success as for the K/T boundary, probably due to additional 300 ma of tectonic and diagenetic overprinting. Another tool is microfacies analysis which is surprisingly rarely used even though it can explain geochemical anomalies or paleontological overlap not detectable by conventional macrofacies analysis. The combination of microfacies analysis and geochemistry was applied at two F-F sections in western Canada and showed how interdependent the two methods are. Additional F-F sections from western Canada, western United States, France, Germany and Australia were sampled or re-sampled and await geochemical/microfacies evaluation.

Last Glacial mammals in South America: a new scenario from the Tarija Basin (Bolivia)

Science.gov (United States)

Coltorti, M.; Abbazzi, L.; Ferretti, M. P.; Iacumin, P.; Rios, F. Paredes; Pellegrini, M.; Pieruccini, P.; Rustioni, M.; Tito, G.; Rook, L.

2007-04-01

The chronology, sedimentary history, and paleoecology of the Tarija Basin (Bolivia), one of the richest Pleistocene mammalian sites in South America, are revised here based on a multidisciplinary study, including stratigraphy, sedimentology, geomorphology, paleontology, isotope geochemistry, and 14C geochronology. Previous studies have indicated a Middle Pleistocene age for this classic locality. We have been able to obtain a series of 14C dates encompassing all the fossil-bearing sequences previously studied in the Tarija Basin. The dated layers range in age from about 44,000 to 21,000 radiocarbon years before present (BP), indicating that the Tarija fauna is much younger than previously thought. Glacial advances correlated to marine isotopic stages (MIS) 4 and 2 (ca. 62 and 20 ka BP, respectively) are also documented at the base and at the very top of the Tarija Padcaya succession, respectively, indicating that the Bolivian Altiplano was not dry but sustained an ice cap during the Last Glacial Maximum. The results of this multidisciplinary study enable us to redefine the chronological limits of the Tarija sequence and of its faunal assemblage and to shift this paleontological, paleoclimatological, and paleoecological framework to the time interval from MIS 4 to MIS 2.

Rodolfo Magin Casamiquela: 1932-2008

Directory of Open Access Journals (Sweden)

Ávila, Luciano Javier

2009-01-01

Full Text Available El pasado 5 de diciembre de 2008 falleció en la ciudad de Cipolletti, Río Negro, el Dr. Rodolfo Magin Casamiquela, investigador retirado del Consejo Nacional de Investigaciones Científicas (CONICET. Casamiquela había nacido en un pequeño pueblo rionegrino, Ingeniero Jacobacci, el 11 de diciembre de 1932. Sin duda alguna, Casamiquela fue uno delos últimos grandes científicos polifacéticos de Argentina dado que sus estudios incluyeron incursiones en la Geología, la Antropología (incluyendo la Arqueología, Lingüística, Etnología, Etnografía, Folklore, Somatología, Zoología, Geología y Paleontología (donde estudió desde la interacción del hombre primitivo con la megafauna, además de reptiles arcosaurios y no arcosaurios, mamíferos, peces, icnitas, tetrápodos en general y anfibios. Es allí en la paleontología, donde hace una excursión hacia la herpetología, publicando una serie de importantes hallazgos de anfibios fósiles, provenientes principalmente de Patagonia.

Big Bend Dam/Lake Sharpe Master Plan, Missouri River, South Dakota: Update of Design Memorandum MB-90

Science.gov (United States)

2003-10-01

and scientifically significant fossil remains which should fill a major gap in the paleontological knowledge of Cretaceous marine deposits...water- skiers and swimmers, ski beaches have been added for convenience, enjoyment, and safety. It is not feasible to provide combined swimming and ski...Only foot traffic, including cross-country skiers and snowshoers, is allowed. A majority of the hikers are from the local Pierre communities. A

Discovery of the oldest .i.Gobius./i. (Teleostei, Gobiiformes) from a marine ecosystem of Early Miocene age

Czech Academy of Sciences Publication Activity Database

Reichenbacher, B.; Gregorová, R.; Holcová, K.; Šanda, R.; Vukić, J.; Přikryl, Tomáš

2018-01-01

Roč. 16, č. 6 (2018), s. 493-513 ISSN 1477-2019 R&D Projects: GA ČR(CZ) GA16-21523S Institutional support: RVO:67985831 Keywords : Gobiidae * Miocene * comparative anatomy * marine ecosystem * Outer Carpathian flysh zone * Outer Carpathian flysch zone * Ždánice-Hustopeče Formation Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 2.963, year: 2016

The mammalian fauna of Barová Cave (Moravian Karst, the Czech Republic)

Czech Academy of Sciences Publication Activity Database

Roblíčková, M.; Káňa, V.; Nývltová Fišáková, Miriam

2017-01-01

Roč. 73, 3-4 (2017), s. 515-532 ISSN 2533-4050 Institutional support: RVO:68081758 Keywords : Quaternary palaeontology * Late Pleistocene * Moravian Karst * Barová Cave * animal assemblage * Ursus ex gr. spelaeus * wintering site * gnawing marks * hunting and scavenging * seasonality * dental age Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology http://fi.nm.cz/wp-content/uploads/2017/12/15_Roblickova_et-al_2017.pdf

Expansion for the Brachylophosaurus canadensis Collagen I Sequence and Additional Evidence of the Preservation of Cretaceous Protein

OpenAIRE

Schroeter, Elena R.; DeHart, Caroline J.; Cleland, Timothy P.; Zheng, Wenxia; Thomas, Paul M.; Kelleher, Neil L.; Bern, Marshall; Schweitzer, Mary H.

2017-01-01

Sequence data from biomolecules such as DNA and proteins, which provide critical information for evolutionary studies, have been assumed to be forever outside the reach of dinosaur paleontology. Proteins, which are predicted to have greater longevity than DNA, have been recovered from two nonavian dinosaurs, but these results remain controversial. For proteomic data derived from extinct Mesozoic organisms to reach their greatest potential for investigating questions of phylogeny and paleobiol...

Geological Society of New Zealand Inc 1999 Annual Conference : programme and abstracts

International Nuclear Information System (INIS)

Wallace, C.

1999-01-01

The call for papers resulted in about 113 oral and 66 poster abstracts being received. These have been loosely assembled under the advertised themes: Hazard Events from a Biological or Paleontological Perspective, Neotectonics of the North Island, Marine Geology, Wanganui Basin, Volcanology, Earth Science Education and Soils, Landscapes and the Environment, Additional to the papers in these themes there has been a wide assortment of General topics. (author)

Extincionismo : catástrofe em massa? Filosofando a ciência ambiental contemporânea através da ideologia pré-eugénica nietzschiana

OpenAIRE

José Filipe P. M. Silva

2016-01-01

This papers aims to realize a philosophical-scientific analysis of the “extinction” problem and, in particular, the «sixth mass extinction». For such, and considering recent paleontological and biological data, we will discuss its scientific realism and epistemic accuracy. We will also have in consideration its theoretical and philosophical vectors, namely the influence of the Nietzschean pre-eugenic (Galtonean) ideology. We will conclude contemporary scientific extinctionism as (...

Archaeological and Historical Investigations of Joe Pool Lake. Recovering Evidence of 6,000 Years of Human Occupation along Mountain Creek in North Central Texas

Science.gov (United States)

1988-04-01

extinct dinosaurs , birds, fish, and humanistic study of man and culture. shells millions of years old are not the subject of scientific inquiry by...archaeologists. Fossils of RESCUE AND CONSERVATION extinct forms of plants and animals are studied by ARCHAEOLOGY specialists educated in paleontology, a...accomplishments achieved to date. Most important- Nile in the 1960s, or the building of the subway ly, it illustrates some of the reasons why our

Galactic Pal-eontology: abundance analysis of the disrupting globular cluster Palomar 5

Science.gov (United States)

Koch, Andreas; Côté, Patrick

2017-05-01

We present a chemical abundance analysis of the tidally disrupted globular cluster (GC) Palomar 5. By co-adding high-resolution spectra of 15 member stars from the cluster's main body, taken at low signal-to-noise with the Keck/HIRES spectrograph, we were able to measure integrated abundance ratios of 24 species of 20 elements including all major nucleosynthetic channels (namely the light element Na; α-elements Mg, Si, Ca, Ti; Fe-peak and heavy elements Sc, V, Cr, Mn, Co, Ni, Cu, Zn; and the neutron-capture elements Y, Zr, Ba, La, Nd, Sm, Eu). The mean metallicity of -1.56 ± 0.02 ± 0.06 dex (statistical and systematic errors) agrees well with the values from individual, low-resolution measurements of individual stars, but it is lower than previous high-resolution results of a small number of stars in the literature. Comparison with Galactic halo stars and other disrupted and unperturbed GCs renders Pal 5 a typical representative of the Milky Way halo population, as has been noted before, emphasizing that the early chemical evolution of such clusters is decoupled from their later dynamical history. We also performed a test as to the detectability of light element variations in this co-added abundance analysis technique and found that this approach is not sensitive even in the presence of a broad range in sodium of 0.6 dex, a value typically found in the old halo GCs. Thus, while methods of determining the global abundance patterns of such objects are well suited to study their overall enrichment histories, chemical distinctions of their multiple stellar populations is still best obtained from measurements of individual stars. Full Table 3 is is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/601/A41

Arroyo del Soldado group: paleontology, dating and Vendian to Lower Cambrian, Uruguay

International Nuclear Information System (INIS)

Gaucher, C.; Sprechmann, P.

1998-01-01

The fossil content of the Vendian to Lower Cambrian Arroyo del Soldado Group of the Nico Perez Terrane of Uruguay is analysed.Organic walled microfossils represented by acritarchs, eukariotic algae (sensu lato) and iron bacteria are recognized. An updated list of these microfossils is presented, which were are now reported in the Yerbal and Barriga Negra formations.Events of weutrphic conditions were reconstructed. The occurrence of Cloudina riemkeae, the earliest known metazoanwith a mineralized skeleton is communicated for the first time in Uruguay. The organic walled microfossils as well as Cloudina riemkeae are indicative of a Vendian age, whereas the trace fossils of the uppermost unit(Cerro Victoria) suggest the Early Cambrian. This would imply that the Group contains the Precambrian-Cambrian boundary. The Arroyo del Soldado Group is correlated with the Jacadiga and Corunba Groups (Brasil) and the Nama Group (Namibia). (author)

A supermatrix analysis of genomic, morphological, and paleontological data from crown Cetacea

Directory of Open Access Journals (Sweden)

Yang Guang

2011-04-01

Full Text Available Abstract Background Cetacea (dolphins, porpoises, and whales is a clade of aquatic species that includes the most massive, deepest diving, and largest brained mammals. Understanding the temporal pattern of diversification in the group as well as the evolution of cetacean anatomy and behavior requires a robust and well-resolved phylogenetic hypothesis. Although a large body of molecular data has accumulated over the past 20 years, DNA sequences of cetaceans have not been directly integrated with the rich, cetacean fossil record to reconcile discrepancies among molecular and morphological characters. Results We combined new nuclear DNA sequences, including segments of six genes (~2800 basepairs from the functionally extinct Yangtze River dolphin, with an expanded morphological matrix and published genomic data. Diverse analyses of these data resolved the relationships of 74 taxa that represent all extant families and 11 extinct families of Cetacea. The resulting supermatrix (61,155 characters and its sub-partitions were analyzed using parsimony methods. Bayesian and maximum likelihood (ML searches were conducted on the molecular partition, and a molecular scaffold obtained from these searches was used to constrain a parsimony search of the morphological partition. Based on analysis of the supermatrix and model-based analyses of the molecular partition, we found overwhelming support for 15 extant clades. When extinct taxa are included, we recovered trees that are significantly correlated with the fossil record. These trees were used to reconstruct the timing of cetacean diversification and the evolution of characters shared by "river dolphins," a non-monophyletic set of species according to all of our phylogenetic analyses. Conclusions The parsimony analysis of the supermatrix and the analysis of morphology constrained to fit the ML/Bayesian molecular tree yielded broadly congruent phylogenetic hypotheses. In trees from both analyses, all Oligocene taxa included in our study fell outside crown Mysticeti and crown Odontoceti, suggesting that these two clades radiated in the late Oligocene or later, contra some recent molecular clock studies. Our trees also imply that many character states shared by river dolphins evolved in their oceanic ancestors, contradicting the hypothesis that these characters are convergent adaptations to fluvial habitats.

Seeking a paleontological signature for mass extinctions caused by flood basalt eruptions

Science.gov (United States)

Payne, J.; Bush, A. M.; Chang, E. T.; Heim, N. A.; Knope, M. L.; Pruss, S. B.

2016-12-01

Flood basalt eruptions coincide with numerous extinction events in the fossil record. Increasingly precise absolute age determinations for both the timing of eruption and of species extinctions have strengthened the case for flood basalt eruptions as the single most important trigger for major mass extinction events in the fossil record. However, the extent to which flood basalt eruptions cause a pattern of biotic loss distinctive from extinctions triggered by other geological or biological processes remains an open question. In the absence of diagnostic mapping between geological triggers and biological losses, establishing the identities of causal agents for mass extinctions will continue to depend primarily on evidence for temporal coincidence. Here we use a synoptic database of marine animal genera spanning the Phanerozoic, including times of first and last occurrence, body size, motility, life position, feeding mode, and respiratory physiology to assess whether extinction events temporally associated with flood basalt eruptions exhibit a diagnostic pattern of extinction selectivity. We further ask whether any events not associated with known large igneous provinces nevertheless display extinction patterns suggestive of such a cause. Finally, we ask whether extinction events associated with other primary causes, such as glaciation or bolide impact, are distinguishable from events apparently triggered by flood basalt eruptions on the basis of extinction selectivity patterns

Paleogene Vertebrate Paleontology, Geology and Remote Sensing in the Wind River Basin

Science.gov (United States)

Stucky, R. K.; Krishtalka, L.

1985-01-01

Biostratigraphic and lithostratigraphic studies were used to correlate different events in the geologic evolution of the northeastern part of the Wind River Basin and have suggested several conclusions. Laterally equivalent exposures of the Lysite member from Cedar Ridge to Bridger Creek show a gradation in lithology from interbedded boulder conglomerates and sandstones to interbedded lenticular sandstones and mudstones to interbedded carbonaceous shales, coals and tabular sandstones. This gradation suggests a shift from alluvial fan to braided stream to paludal or lacustrine sedimentary environments during the late early Eocene. The Lysite and Lost Cabin members of the Wind River Formation are in fault contact in the Bridger Creek area and may intertongue to the east along Cedar Ridge. Ways in which remote sensing could be used in these studies are discussed.

A supermatrix analysis of genomic, morphological, and paleontological data from crown Cetacea

Science.gov (United States)

2011-01-01

Background Cetacea (dolphins, porpoises, and whales) is a clade of aquatic species that includes the most massive, deepest diving, and largest brained mammals. Understanding the temporal pattern of diversification in the group as well as the evolution of cetacean anatomy and behavior requires a robust and well-resolved phylogenetic hypothesis. Although a large body of molecular data has accumulated over the past 20 years, DNA sequences of cetaceans have not been directly integrated with the rich, cetacean fossil record to reconcile discrepancies among molecular and morphological characters. Results We combined new nuclear DNA sequences, including segments of six genes (~2800 basepairs) from the functionally extinct Yangtze River dolphin, with an expanded morphological matrix and published genomic data. Diverse analyses of these data resolved the relationships of 74 taxa that represent all extant families and 11 extinct families of Cetacea. The resulting supermatrix (61,155 characters) and its sub-partitions were analyzed using parsimony methods. Bayesian and maximum likelihood (ML) searches were conducted on the molecular partition, and a molecular scaffold obtained from these searches was used to constrain a parsimony search of the morphological partition. Based on analysis of the supermatrix and model-based analyses of the molecular partition, we found overwhelming support for 15 extant clades. When extinct taxa are included, we recovered trees that are significantly correlated with the fossil record. These trees were used to reconstruct the timing of cetacean diversification and the evolution of characters shared by "river dolphins," a non-monophyletic set of species according to all of our phylogenetic analyses. Conclusions The parsimony analysis of the supermatrix and the analysis of morphology constrained to fit the ML/Bayesian molecular tree yielded broadly congruent phylogenetic hypotheses. In trees from both analyses, all Oligocene taxa included in our study fell outside crown Mysticeti and crown Odontoceti, suggesting that these two clades radiated in the late Oligocene or later, contra some recent molecular clock studies. Our trees also imply that many character states shared by river dolphins evolved in their oceanic ancestors, contradicting the hypothesis that these characters are convergent adaptations to fluvial habitats. PMID:21518443

The diversity and biogeography of late Pleistocene birds from the lowland Neotropics

Science.gov (United States)

Steadman, David W.; Oswald, Jessica A.; Rincón, Ascanio D.

2015-05-01

The Neotropical lowlands sustain the world's richest bird communities, yet little that we know about their history is based on paleontology. Fossils afford a way to investigate distributional shifts in individual species, and thus improve our understanding of long-term change in Neotropical bird communities. We report a species-rich avian fossil sample from a late Pleistocene tar seep (Mene de Inciarte) in northwestern Venezuela. A mere 175 identified fossils from Mene de Inciarte represent 73 species of birds, among which six are extinct, and eight others no longer occur within 100 km. These 14 species consist mainly of ducks (Anatidae), snipe (Scolopacidae), vultures/condors (Vulturidae), hawks/eagles (Accipitridae), and blackbirds (Icteridae). Neotropical bird communities were richer in the late Pleistocene than today; their considerable extinction may be related to collapse of the large mammal fauna at that time. The species assemblage at Mene de Inciarte suggests that biogeographic patterns, even at continental scales, have been remarkably labile over short geological time frames. Mene de Inciarte is but one of 300 + tar seeps in Venezuela, only two of which have been explored for fossils. We may be on the cusp of an exciting new era of avian paleontology in the Neotropics.

The Fact of Evolution: Implications for Science Education

Science.gov (United States)

Hofmann, James R.; Weber, Bruce H.

Creationists who object to evolution in the science curriculum of public schools often cite Jonathan Well's book Icons of Evolution in their support (Wells2000). In the third chapter of his book Wells claims that neither paleontological nor molecular evidence supports the thesis that the history of life is an evolutionary process of descent from preexisting ancestors. We argue that Wells inappropriately relies upon ambiguities inherent in the term `Darwinian' and the phrase `Darwin'stheory'. Furthermore, he does not accurately distinguish between the overwhelming evidence that supports the thesis of common descent and controversies that pertain to causal mechanisms such as natural selection. We also argue that Wells' attempts to undermine the evidence in support of common descent are flawed and his characterization of the relevant data is misleading. In particular, his assessment of the `Cambrian explosion' does not do justice to the fossil record. Nor do his selective references to debate about molecular and paleontological phylogenies constitute a case against common descent. We conclude that the fossil and molecular evidence is more than sufficient to warrant science educators to present common descent as a well-established scientific fact. We also argue that diagrams depicting the `tree of life' can be pedagogically useful as simplified representations of the history of life.

K/Ar dating of the Eastern Rhodope Paleogene magmatism

Energy Technology Data Exchange (ETDEWEB)

Lilov, P.; Yanev, Y.; Marchev, P.

1987-12-01

Paleogene magmatic rocks from the Eastern Rhodope Mountains have seldom been an object of radiogeochronological studies and very few data are available from the geological literature. Until now their dating relied heavily on paleontological data from fossil-bearing sediments, alternating with the lava flows. However, there are also many cross bodies (extrusions, dikes and intrusions) as well as volcanic areas of no sediments or of fossil-free sediments which require the combined use of both methods. This paper aims at characterizing geochronologically the Eastern Rhodope Paleogene volcanism. The K/Ar method was used to date reference volcanoes (mostly with well-defined positions in the Paleogene sequence) associated with the various phases of volcanic activity, as well as some separate intrusive bodies. Nomenclature of volcanics followed the classification of the Soviet Petrographic Commission and that of Peccerillo and Taylor as supplemented by Marchey. The paper characterizes only two of the three main volcanic districts, the Momcilgrad-Arda and the Borovica districts. The third one, Susica district, has restricted exposures near the state boundary between Bulgari and Greece and was excluded from the study. The results obtained are compared with the geochronological scales proposed by Odin and Cavelier and Pomerol which correlate radiogeochronological and paleontological data (nannoplancton data included).

Geologic and geophysical maps of the eastern three-fourths of the Cambria 30' x 60' quadrangle, central California Coast Ranges

Science.gov (United States)

Graymer, R.W.; Langenheim, V.E.; Roberts, M.A.; McDougall, Kristin

2014-01-01

The Cambria 30´ x 60´ quadrangle comprises southwestern Monterey County and northwestern San Luis Obispo County. The land area includes rugged mountains of the Santa Lucia Range extending from the northwest to the southeast part of the map; the southern part of the Big Sur coast in the northwest; broad marine terraces along the southwest coast; and broadvalleys, rolling hills, and modest mountains in the northeast. This report contains geologic, gravity anomaly, and aeromagnetic anomaly maps of the eastern three-fourths of the 1:100,000-scale Cambria quadrangle and the associated geologic and geophysical databases (ArcMap databases), as well as complete descriptions of the geologic map units and the structural relations in the mapped area. A cross section is based on both the geologic map and potential-field geophysical data. The maps are presented as an interactive, multilayer PDF, rather than more traditional pre-formatted map-sheet PDFs. Various geologic, geophysical, paleontological, and base map elements are placed on separate layers, which allows the user to combine elements interactively to create map views beyond the traditional map sheets. Four traditional map sheets (geologic map, gravity map, aeromagnetic map, paleontological locality map) are easily compiled by choosing the associated data layers or by choosing the desired map under Bookmarks.

Quaternary chronostratigraphy and stable isotope paleoecology of Big Bone Lick, Kentucky, USA

Science.gov (United States)

Tankersley, Kenneth Barnett; Murari, Madhav Krishna; Crowley, Brooke E.; Owen, Lewis A.; Storrs, Glenn W.; Mortensen, Litsa

2015-05-01

Big Bone Lick (BBL) in northern Kentucky, USA has been a critical geologic site in the historical development of North American Quaternary vertebrate paleontology since the 1700s. Sedimentology, geoarcheology, paleontology, accelerator mass spectrometry radiocarbon and optically stimulated luminescence dating, and stable carbon and nitrogen isotope analyses were undertaken to develop a chronostratigraphy and history of erosion and deposition for the site to provide a foundation for understanding taphonomy, and species extinction and adaptation to periods of climatic and environmental change. Three geomorphic surfaces are recognized at BBL representing significant periods of floodplain aggradation since the last glacial maximum (26.5-19 ka) dating to the Oldest Dryas (Tazewell, 25-19 ka), the Older Dryas (Cary, 14-12 ka), and late Holocene (5 ka to the present). Unconformities suggest significant periods of degradation during the transitions from cold and dry to warm and moist climates from the Oldest Dryas (Tazewell) to Bølling Oscillation, from the Older Dryas (Cary) to the Allerød, and from the Younger Dryas (Valders) to the Holocene Climatic Optimum. Increased anthropogenic activities since 5 ka may have increased soil upland erosion and floodplain aggradation. Stable isotopes demonstrate that the landscape has been dominated by C3 vegetation since the last glacial maximum.

Důkazy evoluce

OpenAIRE

Korda, Petr

2014-01-01

In this thesis I addressed myself to the literature search of the evidences supporting evolution by natural selection. The aim was to present and describe these evidences. I focused myself on the evidences from the field of paleontology, biogeography and on the similarities based on anatomy, morphology and molecular biology. The conclusion from the literature search is that there exist many arguments supporting evolution by natural selection and further also that proponents of alternative the...

[Key morphofunctional transformations in the evolution of chiropterans (Bats, Chiroptera)].

Science.gov (United States)

Kovaleva, I M

2014-01-01

Study on the morphology and morphogenesis of wing membranes in Bats has revealed some peculiarities in their structure and development. Understanding the embryogenesis of these animals, as well as attraction of data obtained on their molecular genetics and paleontology, allows one to single out some factors that could have initiated evolutionary modifications in development programs. A scenario of the key morphofunctional transformations in the forelimbs during the evolution of chiropterans is given.

Oligocene cetaceans from Baja California Sur, Mexico

OpenAIRE

Hernández Cisneros, Atzcalli Ehécatl; González Barba, Gerardo; Fordyce, Robert Ewan

2017-01-01

Abstract Baja California Sur has an important Cenozoic marine fossil record which includes diverse but poorly known Oligocene cetaceans from Mexico. Here we review the cetacean fossil record including new observations from materials that elucidate the evolution of the Neoceti in the Pacific basin. Fossils were collected from outcrops of the El Cien Formation (Oligocene-Early Miocene) and from San Gregorio Formation (Late Oligocene). The specimens belong to the paleontological collection of Mu...

Mass extinctions and supernova explosions

OpenAIRE

Korschinek, Gunther

2016-01-01

A nearby supernova (SN) explosion could have negatively influenced life on Earth, maybe even been responsible for mass extinctions. Mass extinction poses a significant extinction of numerous species on Earth, as recorded in the paleontologic, paleoclimatic, and geological record of our planet. Depending on the distance between the Sun and the SN, different types of threats have to be considered, such as ozone depletion on Earth, causing increased exposure to the Sun's ultraviolet radiation, o...

Some examples of spin-off technologies: San Carlos de Bariloche

International Nuclear Information System (INIS)

Meyer, Gabriel O.

2001-01-01

The Bariloche Atomic Center (CAB) and the Balseiro Institute, both in San Carlos de Bariloche, are mainly devoted to scientific research and development, the first one; and to education and training the second one. Besides providing specialists in physics and nuclear engineering for research centers in Argentina and abroad, both establishments are transferring technologies and providing services in different fields such as waste management, metallurgy, forensic sciences, medicine, geology, modeling, archaeology, paleontology, etc

Some examples of spin-off technologies: San Carlos de Bariloche; Algunos ejemplos de tecnologias derivadas: San Carlos de Bariloche

Energy Technology Data Exchange (ETDEWEB)

Meyer, Gabriel O [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche

2001-07-01

The Bariloche Atomic Center (CAB) and the Balseiro Institute, both in San Carlos de Bariloche, are mainly devoted to scientific research and development, the first one; and to education and training the second one. Besides providing specialists in physics and nuclear engineering for research centers in Argentina and abroad, both establishments are transferring technologies and providing services in different fields such as waste management, metallurgy, forensic sciences, medicine, geology, modeling, archaeology, paleontology, etc.

Theropoda dinosaurs tracks from Triassic basin nd Ischigualasto - Villa Union, western Argentina

International Nuclear Information System (INIS)

Contreras, V.; Bracco, A.

2004-01-01

The Anchisauripus isp. and Theropoda indet. dinosaurs tracks from the Triassic Los Rastros and Ischigualasto formations, at the Ischigualasto-Villa Union Basin, Western Argentina, are described in this paper. This record completes the paleontological data provided by rest of bones and increases the stratigraphic range of some taxa in which bones are either missing or scarse. On the other hand, this report also allows us to enlarge the faunistic assemblage of some vertebrate assemblages [es

SDAR 1.0 a New Quantitative Toolkit for Analyze Stratigraphic Data

Science.gov (United States)

Ortiz, John; Moreno, Carlos; Cardenas, Andres; Jaramillo, Carlos

2015-04-01

Since the foundation of stratigraphy geoscientists have recognized that data obtained from stratigraphic columns (SC), two dimensional schemes recording descriptions of both geological and paleontological features (e.g., thickness of rock packages, grain size, fossil and lithological components, and sedimentary structures), are key elements for establishing reliable hypotheses about the distribution in space and time of rock sequences, and ancient sedimentary environmental and paleobiological dynamics. Despite the tremendous advances on the way geoscientists store, plot, and quantitatively analyze sedimentological and paleontological data (e.g., Macrostrat [http://www.macrostrat.org/], Paleobiology Database [http://www.paleodb.org/], respectively), there is still a lack of computational methodologies designed to quantitatively examine data from a highly detailed SCs. Moreover, frequently the stratigraphic information is plotted "manually" using vector graphics editors (e.g., Corel Draw, Illustrator), however, this information although store on a digital format, cannot be used readily for any quantitative analysis. Therefore, any attempt to examine the stratigraphic data in an analytical fashion necessarily takes further steps. Given these issues, we have developed the sofware 'Stratigraphic Data Analysis in R' (SDAR), which stores in a database all sedimentological, stratigraphic, and paleontological information collected from a SC, allowing users to generate high-quality graphic plots (including one or multiple features stored in the database). SDAR also encompasses quantitative analyses helping users to quantify stratigraphic information (e.g. grain size, sorting and rounding, proportion of sand/shale). Finally, given that the SDAR analysis module, has been written in the open-source high-level computer language "R graphics/statistics language" [R Development Core Team, 2014], it is already loaded with many of the crucial features required to accomplish basic and

The Nördlingen-Ries Geopark and nearby museums as a natural teaching laboratory for Geoscience students

Science.gov (United States)

Kaminski, Michael; Kaka, SanLinn; Kaminski, Matthew

2017-04-01

The hypervelocity impact of an asteroid in southern Germany around 15 million years ago not only caused an environmental catastrophe, but it also created a scenario that provides us with a world-class natural laboratory for teaching the basic Principles of Geology. The combination of museum visits and observation of rock outcrops enables the student to reinforce or rediscover the basic principles of physical and historical Geology that are presented in first- or second-year Geoscience courses. At KFUPM, our visit to the Ries Geopark begins at the Ries Crater Museum in Nördlingen, where students review knowledge learned in their Physical Geology course: the Nebular Theory, origin of the solar system, and the classification of meteorites based on real examples. Students then learn the stages of impact crater formation, shock metamorphism, and the products of impact crater formation such as tectites, impact breccia and suevite. Students also become familiar with the Mesozoic stratigraphy of Southern Germany, reviewing basic principals of stratigraphy. Visits to local outcrops reinforce the knowledge gained at the Museum. A visit to the nearby Solnhofen Museum and quarries provides insight into the nature of the late Jurassic animals that lived at the edge of the Tethys Sea, reinforcing many topics learned during their second-year Paleontology course, such as taphonomy, and the idea of a death assemblage. At the Museum of the Geosciences Department of the University of Tübingen, the students become familiar with Mesozoic ammonoids as part of their second-year Paleontology course. A visit to the Urwelt Museum and quarry in Holzmaden explores animal life during the Early Jurassic, stratigraphic principles as presented on the museum's "geological staircase", and the origin of petroleum source rocks. The museum houses spectacular examples of Early Jurassic marine reptiles. All knowledge gained in the Jurassic of southern Germany enriches the students' understanding of

Environmental auditing for oil drilling projects

International Nuclear Information System (INIS)

Zambrano Solarte, Hugo Ibsen; Olaya Amaya, Alfredo

2003-01-01

The enforcement of legal regulations on the environment requires some mechanisms related to preservation and conservation of natural resources, as well as paleontological and archaeological wealth, in order to allow their use without endangering their integrity. This article reviews legal regulations, activities and performance indicators, which should be taken into account by Environmental Auditors in oil projects. Additionally, a Plan for Environmental management is analyzed with its main components and procedures for performing the environmental auditing

Identification of the Early Permian (Autunian) in the subsurface of the Ebro Basin, NE Spain, and its paleogeographic consequences

OpenAIRE

Arche, A.; Díez, J.B.; López-Gómez, José

2007-01-01

[EN] The Early Permian (Autunian) has not been identifi ed up to now in the subsurface of the Tertiary Ebro Basin because of the scarcity of oil well boreholes reaching the Variscan basement and the systematic attribution of a Carboniferous age, without any paleontological data, to the unmetamorfosed siliciclastic sediments found at the base of some of them, clearly above the Early Paleozoic basement. Grey and black shale samples recovered from cores preserved in the REPSOL-YPF archi...

230Th/234U age of a Mousterian site in France

International Nuclear Information System (INIS)

Schwarcz, H.P.; Blackwell, B.

1983-01-01

The 230 Th/ 234 U dating method has been used to determine the age of a travertine layer in the Pech 1 cave of Sarlat, South-West France. The reported age of 123 +- 15 kyr is consistent with deposition of this travertine during isotope state 5e, the warmest substage of the last inter-glacial. It is shown that this result is consistent with geological and paleontological estimates of the age of sediments filling the cave. (U.K.)

Corrected placement of Mus-Rattus fossil calibration forces precision in the molecular tree of rodents

OpenAIRE

Kimura, Yuri; Hawkins, Melissa T. R.; McDonough, Molly M.; Jacobs, Louis L.; Flynn, Lawrence J.

2015-01-01

Time calibration derived from the fossil record is essential for molecular phylogenetic and evolutionary studies. Fossil mice and rats, discovered in the Siwalik Group of Pakistan, have served as one of the best-known fossil calibration points in molecular phylogenic studies. Although these fossils have been widely used as the 12 Ma date for the Mus/Rattus split or a more basal split, conclusive paleontological evidence for the nodal assignments has been absent. This study analyzes newly reco...

Stratigraphy and paleontology of Lower Permian rocks north of Cananea, northern Sonora, Mexico

Science.gov (United States)

Blodgett, R.B.; Moore, T.E.; Gray, F.

2002-01-01

Lower Permian carbonate and overlying red bed clastic rocks are present in a 2 km2 stratigraphic window in the vicinity of Rancho La Cueva, Santa Cruz sheet (scale 1:50,000), northern Sonora, Mexico. This exposure lies unconformably beneath predominantly intermediate Upper Cretaceous volcanics yielding 40Ar/39Ar ages of 73.4?? 0.18 and 71.1 ?? 0.35 Ma. The lower part of the Permian succession consists of light- to medium-gray colored limestones of the Colina Limestone, with a minimum thickness of 235 m. Sedimentary features suggest shallow water, slightly restricted depositional environments. Although lacking observable fossils for the most part, two intervals of richly fossiliferous, silicified shell beds are present near the base and top of the Colina Limestone. The lower fauna consist mostly of gastropods and bivalves. The presence of a new microdomatid gastropod species. Glyptospira sonorensis n. sp., close to Glytospira arelela Plas, suggests a late Wolfcampian age for this horizon. The upper fauna are predominantly molluscan dominated (gastropods and bivalves), but some brachiopods (productids and the rhynchonellid genus Pontisia) are also present. Gastropod genera include Bellerophon, Warthia, Euomphalus (represented by the species, Euomphalus kaibabensis Chronic), Baylea, Worthenia, Naticopsis, Goniasma, Kinishbia, Cibecuia, and Glyptospira. The gastropods suggest a Leonardian (late Early Permian) age for this horizon, and many of the species have previously been recorded from the Supai Group and Kaibab Formation of northern and central Arizona. The Colina Limestone is conformably overlain by 11.2 m of light-gray lime mudstone and dolostone, assigned here to the Epitaph Dolomite, which in turn is succeeded by 58.8 m of red-colored sandstone and gray lime mudstone, assigned here to the Scherrer Formation. This Lower Permian succession is significant because it further strengthens the stratigraphic ties of southeastern Arizona rocks with those of northern Sonora and confirms the presence of North American cratonal stratigraphy in the northern part of the state of Sonora, Mexico. Published by Elsevier Science Ltd.

The Pangaean megamonsoon - evidence from the Upper Triassic Chinle Formation, Colorado Plateau

Science.gov (United States)

Dubiel, R.F.; Totman, Parrish J.; Parrish, J.M.; Good, S.C.

1991-01-01

The Chinle was deposited between about 5?? to 15??N paleolatitude in the western equatorial region of Pangaea, a key area for documenting the effects of the monsoonal climate. This study summarizes sedimentological and paleontologic data from the Chinle Formation on the Colorado Plateau and integrates that data with paleoclimatic models. The evidence for abundant moisture and seasonality attest to the reversal of equatorial flow and support the hypothesis that the Triassic Pangaean climate was dominated by monsoonal circulation. -from Authors

Climatic influences on species: Evidence from the fossil record

Science.gov (United States)

Cronin, T. M.; Schneider, C.E.

1990-01-01

The detailed Neogene and Quaternary paleoclimatic reconstructions now available provide a means to test how species respond to environmental change. Paleontologic studies of marine organisms show that climatic change causes evolution (via cladogenesis and anagenesis), ecophenotypic variation, migration, morphologic stasis and extinction. Evolution during climatic change is a rare event relative to the number of climatic cycles that have occurred, but climate-related environmental barriers, usually temperature, may play an important role in the isolation of populations during allopatric speciation.

Genetic evidence for patrilocal mating behavior among Neandertal groups

DEFF Research Database (Denmark)

Lalueza-Fox, Carles; Rosas, Antonio; Estalrrich, Almudena

2011-01-01

The remains of 12 Neandertal individuals have been found at the El Sidrón site (Asturias, Spain), consisting of six adults, three adolescents, two juveniles, and one infant. Archaeological, paleontological, and geological evidence indicates that these individuals represent all or part of a contem...... of the three adult females carried different mtDNA lineages. These findings provide evidence to indicate that Neandertal groups not only were small and characterized by low genetic diversity but also were likely to have practiced patrilocal mating behavior....

Edad de la formación vijes en el pozo v3a, oligoceno del piedemonte oriental de la cordillera occidental, departamento del valle del cauca, colombia

OpenAIRE

Dueñas, Hernando; Navarrete, Rosa Esther; Mojica, Jairo; Pardo, Mauricio; Camargo, Roger

2012-01-01

Outcrops of the Vijes Formation are restricted to the Vijes and Mulaló areas, which are located in the northwestern part of the Valle del Cauca Basin. Based on its micro-paleontological content (palynomorphs and forams) an Oligocene age has been assigned for this Marine Unit for long time considered as an Eocene to Miocene Formation. The Vijes Formation, has a thickness close to 180 m. It is made up of limestones, dirty sandstones and calcareous siltstones, that allow to sub-divide it in four...

Por qué el ser humano crea obras artísticas

OpenAIRE

Velasco, Pedro

2004-01-01

Con base en los resultados que aportan la paleontología, los hallazgos neunoanatómicos cerebrales y el estudio neuroexperimental de las emociones, cuyos resultados se extrapolan a la que es esencial, específicamente humana, la angustía, se plantea que el hominido en su largo camino de la evolución desarrolló las estructuras y funciones necesarias para enfrentar exitosamente al medio ambiente, siempre hostil, y que estimulado por la angustia dejó (y sigue dejando) constancia de su paso por el ...

Oxygen - A Four Billion Year History

DEFF Research Database (Denmark)

Canfield, Donald Eugene

of fields, including geology, paleontology, geochemistry, biochemistry, animal physiology, and microbiology, to explain why our oxygenated Earth became the ideal place for life. Describing which processes, both biological and geological, act to control oxygen levels in the atmosphere, Canfield traces...... guides readers through the various lines of scientific evidence, considers some of the wrong turns and dead ends along the way, and highlights the scientists and researchers who have made key discoveries in the field. Showing how Earth's atmosphere developed over time, Oxygen takes readers...

Radioecological studies at the National Accelerator Centre based on the determination of 129I by accelerator mass spectrometry (AMS)

International Nuclear Information System (INIS)

Lopez-Gutierrez, J. M.; Gomez-Guzman, J. M.; Chamizo, E.; Santos, F. J.; Garcia-Leon, M.; Garcia-Tenorio, R.

2013-01-01

Since 2006 a compact system of mass spectrometry with Accelerator (AMS) is installed at the National Center of Accelerators, Seville. After an initial set-up and study have been opening many lines of research in fields such as archeology, geology, paleontology, oceanography, oceanography, internal dosimetry and characterization of radioactive waste, among others. In particular, based on the measurement of 1 29I have made contributions to the field of radioecology and radiation protection. In this work they are summarized and presented some of these investigations. (Author)

Mapping prehistoric ghosts in the synchrotron

Energy Technology Data Exchange (ETDEWEB)

Edwards, N.P.; Wogelius, R.A. [University of Manchester, School of Earth, Atmospheric, and Environmental Sciences, Manchester (United Kingdom); University of Manchester, Williamson Research Centre for Molecular Environmental Science, Manchester (United Kingdom); Bergmann, U. [SLAC National Accelerator Laboratory, Linac Coherent Light Source, Menlo Park, CA (United States); Larson, P. [Black Hills Institute of Geological Research, Inc., Hill City, SD (United States); Sellers, W.I. [University of Manchester, Faculty of Life Sciences, Manchester (United Kingdom); Manning, P.L. [University of Manchester, School of Earth, Atmospheric, and Environmental Sciences, Manchester (United Kingdom); University of Manchester, Williamson Research Centre for Molecular Environmental Science, Manchester (United Kingdom); University of Pennsylvania, Department of Earth and Environmental Science, Philadelphia, PA (United States)

2013-04-15

The detailed chemical analysis of fossils has the potential to reveal great insight to the composition, preservation and biochemistry of ancient life. Such analyses would ideally identify, quantify, and spatially resolve the chemical composition of preserved bone and soft tissue structures, but also the embedding matrix. Mapping the chemistry of a fossil in situ can place constraints on mass transfer between the enclosing matrix and the preserved organism(s), and therefore aid in distinguishing taphonomic processes from original chemical zonation remnant within the fossils themselves. Conventional analytical methods, such as scanning electron microscopy (SEM) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) have serious limitations in this case, primarily, an inability to provide large (i.e., decimeter) scale chemical maps. Additionally, vacuum chamber size and the need for destructive sampling preclude analysis of large and precious fossil specimens. However, the recent development of Synchrotron Rapid Scanning X-ray Fluorescence (SRS-XRF) at the Stanford Synchrotron Radiation Lightsource (SSRL) allows the non-destructive chemical analysis and imaging of major, minor, and trace element concentrations of large paleontological and archeological specimens in rapid scanning times. Here we present elemental maps of a fossil reptile produced using the new SRS-XRF method. Our results unequivocally show that preserved biological structures are not simply impressions or carbonized remains, but possess a remnant of the original organismal biochemistry. We show that SRS-XRF is a powerful new tool for the study of paleontological and archaeological samples. (orig.)

Simple versus complex models of trait evolution and stasis as a response to environmental change

Science.gov (United States)

Hunt, Gene; Hopkins, Melanie J.; Lidgard, Scott

2015-04-01

Previous analyses of evolutionary patterns, or modes, in fossil lineages have focused overwhelmingly on three simple models: stasis, random walks, and directional evolution. Here we use likelihood methods to fit an expanded set of evolutionary models to a large compilation of ancestor-descendant series of populations from the fossil record. In addition to the standard three models, we assess more complex models with punctuations and shifts from one evolutionary mode to another. As in previous studies, we find that stasis is common in the fossil record, as is a strict version of stasis that entails no real evolutionary changes. Incidence of directional evolution is relatively low (13%), but higher than in previous studies because our analytical approach can more sensitively detect noisy trends. Complex evolutionary models are often favored, overwhelmingly so for sequences comprising many samples. This finding is consistent with evolutionary dynamics that are, in reality, more complex than any of the models we consider. Furthermore, the timing of shifts in evolutionary dynamics varies among traits measured from the same series. Finally, we use our empirical collection of evolutionary sequences and a long and highly resolved proxy for global climate to inform simulations in which traits adaptively track temperature changes over time. When realistically calibrated, we find that this simple model can reproduce important aspects of our paleontological results. We conclude that observed paleontological patterns, including the prevalence of stasis, need not be inconsistent with adaptive evolution, even in the face of unstable physical environments.

Formation of tomographic images with neutrons

International Nuclear Information System (INIS)

Duarte, A.; Tenreiro, C; Valencia, J; Steinman, G.; Henriquez, C

2000-01-01

The possibility of having a non-destructive method of analysis for archaeological and paleontological samples is of interest. A special group of fossil samples has come to our attention, which because of their value should be preserved and, therefore, the availability of an indirect, non-destructive, non contaminating analytical technique is important. The strong absorption of usual kinds of radiation by a fossilized sample restricts the application of conventional methods of analysis. A type of radiation that is not completely attenuated by thick samples, in sizes that are typical in paleontology, is necessary. Neutrons may be considered as an ideal non-invasive probe with the possibility of developing a technique for the formation and analysis of images. A technique has been developed for the spatial reconstruction of the contents of a fossilized sample (tomography) with neutrons, without touching or altering the sample in any way. The neutron beam was extracted from the RECH-1 reactor belonging to the CCHEN, La Reina. The tomographic images of the contents of a fossilized egg are presented for the first time and represent views or cuts of the content as well as a set that permits the three dimensional reconstruction of the inside of the object and its subsequent animation in graphic format. This project developed a technique for taking neutron radiographs of this kind of sample including the numerical algorithms and the treatment and formation of the images (CW)

A Contribuição dos Museus para a Institucionalização e Difusão da Paleontologia.

Directory of Open Access Journals (Sweden)

Ana Carolina Maciel Vieira

2007-07-01

Full Text Available Since the calls “cabinets of curiosities", the essence of natural history was consolidating itself with the birth of the museums and the development of the Museums of Natural History. This consolidation was reached through following activities: expeditions, field trips, collection classification works, catalogues of diffusion of scientific knowledge, educativ activities and expositions. The present paper intends to discuss the importance of the museal institutions for the studies of Paleontology; since the museums of Natural History had exerted a pioneering paper in the institutionalization of certain areas of knowledge, as Palaeontology, Anthropology and Experimental Physiology, in Brazil. The Paleontological studies in museums had collaborated in the specialization and modernization of the appearance of "new museum idea". As this new concept the museum is a space of diffusion of scientific knowledge, represented as an object that reflects the identity of the society without an obligator linking with physical constructions. However, the Brazilian museums have been sufficientlyobsolete, with problems that involve acquisition and maintenance of collections to production of temporary or permanent exhibitions. When the Brazilian institutions of natural history are analyzed they are not organized on the new museum conception and the digital age as the North American and European ones. Despite the difficulties found by the Museums since its birth as Institution in the 18th century, the contemporary development of Museology and Palaeontology as Science had contributed for the consolidation and institutionalization of both, helping the diffusion of scientific knowledge.

The identification of proteoglycans and glycosaminoglycans in archaeological human bones and teeth.

Science.gov (United States)

Coulson-Thomas, Yvette M; Coulson-Thomas, Vivien J; Norton, Andrew L; Gesteira, Tarsis F; Cavalheiro, Renan P; Meneghetti, Maria Cecília Z; Martins, João R; Dixon, Ronald A; Nader, Helena B

2015-01-01

Bone tissue is mineralized dense connective tissue consisting mainly of a mineral component (hydroxyapatite) and an organic matrix comprised of collagens, non-collagenous proteins and proteoglycans (PGs). Extracellular matrix proteins and PGs bind tightly to hydroxyapatite which would protect these molecules from the destructive effects of temperature and chemical agents after death. DNA and proteins have been successfully extracted from archaeological skeletons from which valuable information has been obtained; however, to date neither PGs nor glycosaminoglycan (GAG) chains have been studied in archaeological skeletons. PGs and GAGs play a major role in bone morphogenesis, homeostasis and degenerative bone disease. The ability to isolate and characterize PG and GAG content from archaeological skeletons would unveil valuable paleontological information. We therefore optimized methods for the extraction of both PGs and GAGs from archaeological human skeletons. PGs and GAGs were successfully extracted from both archaeological human bones and teeth, and characterized by their electrophoretic mobility in agarose gel, degradation by specific enzymes and HPLC. The GAG populations isolated were chondroitin sulfate (CS) and hyaluronic acid (HA). In addition, a CSPG was detected. The localization of CS, HA, three small leucine rich PGs (biglycan, decorin and fibromodulin) and glypican was analyzed in archaeological human bone slices. Staining patterns were different for juvenile and adult bones, whilst adolescent bones had a similar staining pattern to adult bones. The finding that significant quantities of PGs and GAGs persist in archaeological bones and teeth opens novel venues for the field of Paleontology.

A phylogenetic blueprint for a modern whale.

Science.gov (United States)

Gatesy, John; Geisler, Jonathan H; Chang, Joseph; Buell, Carl; Berta, Annalisa; Meredith, Robert W; Springer, Mark S; McGowen, Michael R

2013-02-01

The emergence of Cetacea in the Paleogene represents one of the most profound macroevolutionary transitions within Mammalia. The move from a terrestrial habitat to a committed aquatic lifestyle engendered wholesale changes in anatomy, physiology, and behavior. The results of this remarkable transformation are extant whales that include the largest, biggest brained, fastest swimming, loudest, deepest diving mammals, some of which can detect prey with a sophisticated echolocation system (Odontoceti - toothed whales), and others that batch feed using racks of baleen (Mysticeti - baleen whales). A broad-scale reconstruction of the evolutionary remodeling that culminated in extant cetaceans has not yet been based on integration of genomic and paleontological information. Here, we first place Cetacea relative to extant mammalian diversity, and assess the distribution of support among molecular datasets for relationships within Artiodactyla (even-toed ungulates, including Cetacea). We then merge trees derived from three large concatenations of molecular and fossil data to yield a composite hypothesis that encompasses many critical events in the evolutionary history of Cetacea. By combining diverse evidence, we infer a phylogenetic blueprint that outlines the stepwise evolutionary development of modern whales. This hypothesis represents a starting point for more detailed, comprehensive phylogenetic reconstructions in the future, and also highlights the synergistic interaction between modern (genomic) and traditional (morphological+paleontological) approaches that ultimately must be exploited to provide a rich understanding of evolutionary history across the entire tree of Life. Copyright © 2012 Elsevier Inc. All rights reserved.

Preparing new Earth Science teachers via a collaborative program between Research Scientists and Educators

Science.gov (United States)

Grcevich, Jana; Pagnotta, Ashley; Mac Low, Mordecai-Mark; Shara, Michael; Flores, Kennet; Nadeau, Patricia A.; Sessa, Jocelyn; Ustunisik, Gokce; Zirakparvar, Nasser; Ebel, Denton; Harlow, George; Webster, James D.; Kinzler, Rosamond; MacDonald, Maritza B.; Contino, Julie; Cooke-Nieves, Natasha; Howes, Elaine; Zachowski, Marion

2015-01-01

The Master of Arts in Teaching (MAT) Program at the American Museum of Natural History is a innovative program designed to prepare participants to be world-class Earth Science teachers. New York State is experiencing a lack of qualified Earth Science teachers, leading in the short term to a reduction in students who successfully complete the Earth Science Regents examination, and in the long term potential reductions in the number of students who go on to pursue college degrees in Earth Science related disciplines. The MAT program addresses this problem via a collaboration between practicing research scientists and education faculty. The faculty consists of curators and postdoctoral researchers from the Departments of Astrophysics, Earth and Planetary Sciences, and the Division of Paleontology, as well as doctoral-level education experts. During the 15-month, full-time program, students participate in a residency program at local urban classrooms as well as taking courses and completing field work in astrophysics, geology, earth science, and paleontology. The program targets high-needs schools with diverse populations. We seek to encourage, stimulate interest, and inform the students impacted by our program, most of whom are from traditionally underrepresented backgrounds, about the rich possibilities for careers in Earth Science related disciplines and the intrinsic value of the subject. We report on the experience of the first and second cohorts, all of whom are now employed in full time teaching positions, and the majority in high needs schools in New York State.

The evolutionary origin of the turtle shell and its dependence on the axial arrest of the embryonic rib cage.

Science.gov (United States)

Hirasawa, Tatsuya; Pascual-Anaya, Juan; Kamezaki, Naoki; Taniguchi, Mari; Mine, Kanako; Kuratani, Shigeru

2015-05-01

Turtles are characterized by their possession of a shell with dorsal and ventral moieties: the carapace and the plastron, respectively. In this review, we try to provide answers to the question of the evolutionary origin of the carapace, by revising morphological, developmental, and paleontological comparative analyses. The turtle carapace is formed through modification of the thoracic ribs and vertebrae, which undergo extensive ossification to form a solid bony structure. Except for peripheral dermal elements, there are no signs of exoskeletal components ontogenetically added to the costal and neural bones, and thus the carapace is predominantly of endoskeletal nature. Due to the axial arrest of turtle rib growth, the axial part of the embryo expands laterally and the shoulder girdle becomes encapsulated in the rib cage, together with the inward folding of the lateral body wall in the late phase of embryogenesis. Along the line of this folding develops a ridge called the carapacial ridge (CR), a turtle-specific embryonic structure. The CR functions in the marginal growth of the carapacial primordium, in which Wnt signaling pathway might play a crucial role. Both paleontological and genomic evidence suggest that the axial arrest is the first step toward acquisition of the turtle body plan, which is estimated to have taken place after the divergence of a clade including turtles from archosaurs. The developmental relationship between the CR and the axial arrest remains a central issue to be solved in future. © 2014 Wiley Periodicals, Inc.

Microbial Mats: the implication of these microbial communities in early stages of fossilization

OpenAIRE

Iniesto Rodríguez, Miguel

2016-01-01

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Ecología. Fecha de lectura: 03-03-2016 Esta tesis tiene embargado el acceso al texto completo hasta el 03-09-2017 Durante décadas la paleontología ha tratado de establecer los mecanismos que pudieran explicar la génesis de los Konservat-Lagerstätten, yacimientos paleontológicos que se caracterizan por la excepcional preservación de sus restos. Estos fósiles mantienen en algu...

Sr isotope stratigraphy of some Rupelian carbonated laminites from the Limagne Basin: influence of seawater in the rift of the French Massif central?

International Nuclear Information System (INIS)

Briot, D.; Poidevin, J.L.

1998-01-01

87 Sr/ 86 Sr ratios of biogenic and abiotic calcites Upper Rupelian sediments in the Limagne rift (French Massif Central) define a smooth and regular negative correlation with time interrupted by repetitive sharp peaks; the progressive drop in isotopic ratio can be explained by the geological evolution of the river basin through time. Negative peaks are explained by synsedimentary volcanism, repeated marine incursions, or leaching of ancient evaporites. Comparison with available paleontologic data does not favour the volcanic explanation, but rather the influence of Rupelian marine waters. (authors)

Vertebrate paleontology, stratigraphy, and paleohydrology of Tule Springs Fossil Beds National Monument, Nevada (USA)

Science.gov (United States)

Springer, Kathleen; Pigati, Jeffery S.; Scott, Eric

2017-01-01

Tule Springs Fossil Beds National Monument (TUSK) preserves 22,650 acres of the upper Las Vegas Wash in the northern Las Vegas Valley (Nevada, USA). TUSK is home to extensive and stratigraphically complex groundwater discharge (GWD) deposits, called the Las Vegas Formation, which represent springs and desert wetlands that covered much of the valley during the late Quaternary. The GWD deposits record hydrologic changes that occurred here in a dynamic and temporally congruent response to abrupt climatic oscillations over the last ~300 ka (thousands of years). The deposits also entomb the Tule Springs Local Fauna (TSLF), one of the most significant late Pleistocene (Rancholabrean) vertebrate assemblages in the American Southwest. The TSLF is both prolific and diverse, and includes a large mammal assemblage dominated by Mammuthus columbi and Camelops hesternus. Two (and possibly three) distinct species of Equus, two species of Bison, Panthera atrox, Smilodon fatalis, Canis dirus, Megalonyx jeffersonii, and Nothrotheriops shastensis are also present, and newly recognized faunal components include micromammals, amphibians, snakes, and birds. Invertebrates, plant macrofossils, and pollen also occur in the deposits and provide important and complementary paleoenvironmental information. This field compendium highlights the faunal assemblage in the classic stratigraphic sequences of the Las Vegas Formation within TUSK, emphasizes the significant hydrologic changes that occurred in the area during the recent geologic past, and examines the subsequent and repeated effect of rapid climate change on the local desert wetland ecosystem.

Testing sequential extraction methods for the analysis of multiple stable isotope systems from a bone sample

Science.gov (United States)

Sahlstedt, Elina; Arppe, Laura

2017-04-01

Stable isotope composition of bones, analysed either from the mineral phase (hydroxyapatite) or from the organic phase (mainly collagen) carry important climatological and ecological information and are therefore widely used in paleontological and archaeological research. For the analysis of the stable isotope compositions, both of the phases, hydroxyapatite and collagen, have their more or less well established separation and analytical techniques. Recent development in IRMS and wet chemical extraction methods have facilitated the analysis of very small bone fractions (500 μg or less starting material) for PO43-O isotope composition. However, the uniqueness and (pre-) historical value of each archaeological and paleontological finding lead to preciously little material available for stable isotope analyses, encouraging further development of microanalytical methods for the use of stable isotope analyses. Here we present the first results in developing extraction methods for combining collagen C- and N-isotope analyses to PO43-O-isotope analyses from a single bone sample fraction. We tested sequential extraction starting with dilute acid demineralization and collection of both collagen and PO43-fractions, followed by further purification step by H2O2 (PO43-fraction). First results show that bone sample separates as small as 2 mg may be analysed for their δ15N, δ13C and δ18OPO4 values. The method may be incorporated in detailed investigation of sequentially developing skeletal material such as teeth, potentially allowing for the investigation of interannual variability in climatological/environmental signals or investigation of the early life history of an individual.

The evolutionary continuum of limb function from early theropods to birds.

Science.gov (United States)

Hutchinson, John R; Allen, Vivian

2009-04-01

The bipedal stance and gait of theropod dinosaurs evolved gradually along the lineage leading to birds and at some point(s), flight evolved. How and when did these changes occur? We review the evidence from neontology and paleontology, including pectoral and pelvic limb functional morphology, fossil footprints/trackways and biomechanical models and simulations. We emphasise that many false dichotomies or categories have been applied to theropod form and function, and sometimes, these impede research progress. For example, dichotomisation of locomotor function into 'non-avian' and 'avian' modes is only a conceptual crutch; the evidence supports a continuous transition. Simplification of pelvic limb function into cursorial/non-cursorial morphologies or flexed/columnar poses has outlived its utility. For the pectoral limbs, even the classic predatory strike vs. flight wing-stroke distinction and separation of theropods into non-flying and flying--or terrestrial and arboreal--categories may be missing important subtleties. Distinguishing locomotor function between taxa, even with quantitative approaches, will always be fraught with ambiguity, making it difficult to find real differences if that ambiguity is properly acknowledged. There must be an 'interpretive asymptote' for reconstructing dinosaur limb function that available methods and evidence cannot overcome. We may be close to that limit, but how far can it be stretched with improved methods and evidence, if at all? The way forward is a combination of techniques that emphasises integration of neontological and paleontological evidence and quantitative assessment of limb function cautiously applied with validated techniques and sensitivity analysis of unknown variables.

Phylogeography of screaming hairy armadillo Chaetophractus vellerosus: Successive disjunctions and extinctions due to cyclical climatic changes in southern South America.

Science.gov (United States)

Poljak, Sebastián; Ferreiro, Alejandro M; Chiappero, Marina B; Sánchez, Julieta; Gabrielli, Magalí; Lizarralde, Marta S

2018-01-01

Little is known about phylogeography of armadillo species native to southern South America. In this study we describe the phylogeography of the screaming hairy armadillo Chaetophractus vellerosus, discuss previous hypothesis about the origin of its disjunct distribution and propose an alternative one, based on novel information on genetic variability. Variation of partial sequences of mitochondrial DNA Control Region (CR) from 73 individuals from 23 localities were analyzed to carry out a phylogeographic analysis using neutrality tests, mismatch distribution, median-joining (MJ) network and paleontological records. We found 17 polymorphic sites resulting in 15 haplotypes. Two new geographic records that expand known distribution of the species are presented; one of them links the distributions of recently synonimized species C. nationi and C. vellerosus. Screaming hairy armadillo phylogeographic pattern can be addressed as category V of Avise: common widespread linages plus closely related lineages confined to one or a few nearby locales each. The older linages are distributed in the north-central area of the species distribution range in Argentina (i.e. ancestral area of distribution). C. vellerosus seems to be a low vagility species that expanded, and probably is expanding, its distribution range while presents signs of genetic structuring in central areas. To explain the disjunct distribution, a hypothesis of extinction of the species in intermediate areas due to quaternary climatic shift to more humid conditions was proposed. We offer an alternative explanation: long distance colonization, based on null genetic variability, paleontological record and evidence of alternance of cold/arid and temperate/humid climatic periods during the last million years in southern South America.

The identification of proteoglycans and glycosaminoglycans in archaeological human bones and teeth.

Directory of Open Access Journals (Sweden)

Yvette M Coulson-Thomas

Full Text Available Bone tissue is mineralized dense connective tissue consisting mainly of a mineral component (hydroxyapatite and an organic matrix comprised of collagens, non-collagenous proteins and proteoglycans (PGs. Extracellular matrix proteins and PGs bind tightly to hydroxyapatite which would protect these molecules from the destructive effects of temperature and chemical agents after death. DNA and proteins have been successfully extracted from archaeological skeletons from which valuable information has been obtained; however, to date neither PGs nor glycosaminoglycan (GAG chains have been studied in archaeological skeletons. PGs and GAGs play a major role in bone morphogenesis, homeostasis and degenerative bone disease. The ability to isolate and characterize PG and GAG content from archaeological skeletons would unveil valuable paleontological information. We therefore optimized methods for the extraction of both PGs and GAGs from archaeological human skeletons. PGs and GAGs were successfully extracted from both archaeological human bones and teeth, and characterized by their electrophoretic mobility in agarose gel, degradation by specific enzymes and HPLC. The GAG populations isolated were chondroitin sulfate (CS and hyaluronic acid (HA. In addition, a CSPG was detected. The localization of CS, HA, three small leucine rich PGs (biglycan, decorin and fibromodulin and glypican was analyzed in archaeological human bone slices. Staining patterns were different for juvenile and adult bones, whilst adolescent bones had a similar staining pattern to adult bones. The finding that significant quantities of PGs and GAGs persist in archaeological bones and teeth opens novel venues for the field of Paleontology.

Revised geochronology, correlation, and dinosaur stratigraphic ranges of the Santonian-Maastrichtian (Late Cretaceous) formations of the Western Interior of North America.

Science.gov (United States)

Fowler, Denver Warwick

2017-01-01

Interbasinal stratigraphic correlation provides the foundation for all consequent continental-scale geological and paleontological analyses. Correlation requires synthesis of lithostratigraphic, biostratigraphic and geochronologic data, and must be periodically updated to accord with advances in dating techniques, changing standards for radiometric dates, new stratigraphic concepts, hypotheses, fossil specimens, and field data. Outdated or incorrect correlation exposes geological and paleontological analyses to potential error. The current work presents a high-resolution stratigraphic chart for terrestrial Late Cretaceous units of North America, combining published chronostratigraphic, lithostratigraphic, and biostratigraphic data. 40Ar / 39Ar radiometric dates are newly recalibrated to both current standard and decay constant pairings. Revisions to the stratigraphic placement of most units are slight, but important changes are made to the proposed correlations of the Aguja and Javelina formations, Texas, and recalibration corrections in particular affect the relative age positions of the Belly River Group, Alberta; Judith River Formation, Montana; Kaiparowits Formation, Utah; and Fruitland and Kirtland formations, New Mexico. The stratigraphic ranges of selected clades of dinosaur species are plotted on the chronostratigraphic framework, with some clades comprising short-duration species that do not overlap stratigraphically with preceding or succeeding forms. This is the expected pattern that is produced by an anagenetic mode of evolution, suggesting that true branching (speciation) events were rare and may have geographic significance. The recent hypothesis of intracontinental latitudinal provinciality of dinosaurs is shown to be affected by previous stratigraphic miscorrelation. Rapid stepwise acquisition of display characters in many dinosaur clades, in particular chasmosaurine ceratopsids, suggests that they may be useful for high resolution biostratigraphy.

Amphibians as indicators of early tertiary "out-of-India" dispersal of vertebrates.

Science.gov (United States)

Bossuyt, F; Milinkovitch, M C

2001-04-06

Sixty-five million years ago, massive volcanism produced on the India-Seychelles landmass the largest continental lava deposit (Deccan Traps) of the past 200 million years. Using a molecular clock-independent approach for inferring dating information from molecular phylogenies, we show that multiple lineages of frogs survived Deccan Traps volcanism after millions of years of isolation on drifting India. The collision between the Indian and Eurasian plates was followed by wide dispersal of several of these lineages. This "out-of-India" scenario reveals a zoogeographical pattern that might reconcile paleontological and molecular data in other vertebrate groups.

The Wunstorf Drilling Project: Coring a Global Stratigraphic Reference Section of the Oceanic Anoxic Event 2

Directory of Open Access Journals (Sweden)

Markus Wilmsen

2007-03-01

Full Text Available The Wunstorf drilling project aims at establishing a high resolution stable isotope record for the black shale succession (OAE 2 of the CTBI and developing this into a globally applicable high resolutionbio- and chemostratigraphic reference section. Disciplines involved include micropaleontology (calcareous nannofossils, planktonic foraminifera, macropaleontology (ammonites, inoceramids, stable isotopes and cyclostratigraphy mainly based on borehole logging, multisensor core logging, and x-ray flflfluorescence (XRF scanning data. The combination of geochemical, paleontological, and logging data will allow high resolution chemo- and biostratigraphy for the CTBI which may in the future serve as an international standard.

Characterization of fossil remains using XRF, XPS and XAFS spectroscopies

International Nuclear Information System (INIS)

Zougrou, I M; Katsikini, M; Pinakidou, F; Paloura, E C; Brzhezinskaya, M; Papadopoulou, L; Vlachos, E; Tsoukala, E

2016-01-01

Synchrotron radiation micro-X-Ray Fluorescence (μ-XRF), X-ray photoelectron (XPS) and X-ray Absorption Fine Structure (XAFS) spectroscopies are applied for the study of paleontological findings. More specifically the costal plate of a gigantic terrestrial turtle Titanochelon bacharidisi and a fossilized coprolite of the cave spotted hyena Crocuta crocuta spelaea are studied. Ca L 2,3 -edge NEXAFS and Ca 2p XPS are applied for the identification and quantification of apatite and Ca containing minerals. XRF mapping and XAFS are employed for the study of the spatial distribution and speciation of the minerals related to the deposition environment. (paper)

Surface Model and Tomographic Archive of Fossil Primate and Other Mammal Holotype and Paratype Specimens of the Ditsong National Museum of Natural History, Pretoria, South Africa.

Directory of Open Access Journals (Sweden)

Justin W Adams

Full Text Available Nearly a century of paleontological excavation and analysis from the cave deposits of the Cradle of Humankind UNESCO World Heritage Site in northeastern South Africa underlies much of our understanding of the evolutionary history of hominins, other primates and other mammal lineages in the late Pliocene and early Pleistocene of Africa. As one of few designated fossil repositories, the Plio-Pleistocene Palaeontology Section of the Ditsong National Museum of Natural History (DNMNH; the former Transvaal Museum curates much of the mammalian faunas recovered from the fossil-rich deposits of major South African hominin-bearing localities, including the holotype and paratype specimens of many primate, carnivore, and other mammal species (Orders Primates, Carnivora, Artiodactyla, Eulipotyphla, Hyracoidea, Lagomorpha, Perissodactyla, and Proboscidea. Here we describe an open-access digital archive of high-resolution, full-color three-dimensional (3D surface meshes of all 89 non-hominin holotype, paratype and significant mammalian specimens curated in the Plio-Pleistocene Section vault. Surface meshes were generated using a commercial surface scanner (Artec Spider, Artec Group, Luxembourg, are provided in formats that can be opened in both open-source and commercial software, and can be readily downloaded either via an online data repository (MorphoSource or via direct request from the DNMNH. In addition to providing surface meshes for each specimen, we also provide tomographic data (both computerized tomography [CT] and microfocus [microCT] for a subset of these fossil specimens. This archive of the DNMNH Plio-Pleistocene collections represents the first research-quality 3D datasets of African mammal fossils to be made openly available. This simultaneously provides the paleontological community with essential baseline information (e.g., updated listing and 3D record of specimens in their current state of preservation and serves as a single resource of

Surface Model and Tomographic Archive of Fossil Primate and Other Mammal Holotype and Paratype Specimens of the Ditsong National Museum of Natural History, Pretoria, South Africa.

Science.gov (United States)

Adams, Justin W; Olah, Angela; McCurry, Matthew R; Potze, Stephany

2015-01-01

Nearly a century of paleontological excavation and analysis from the cave deposits of the Cradle of Humankind UNESCO World Heritage Site in northeastern South Africa underlies much of our understanding of the evolutionary history of hominins, other primates and other mammal lineages in the late Pliocene and early Pleistocene of Africa. As one of few designated fossil repositories, the Plio-Pleistocene Palaeontology Section of the Ditsong National Museum of Natural History (DNMNH; the former Transvaal Museum) curates much of the mammalian faunas recovered from the fossil-rich deposits of major South African hominin-bearing localities, including the holotype and paratype specimens of many primate, carnivore, and other mammal species (Orders Primates, Carnivora, Artiodactyla, Eulipotyphla, Hyracoidea, Lagomorpha, Perissodactyla, and Proboscidea). Here we describe an open-access digital archive of high-resolution, full-color three-dimensional (3D) surface meshes of all 89 non-hominin holotype, paratype and significant mammalian specimens curated in the Plio-Pleistocene Section vault. Surface meshes were generated using a commercial surface scanner (Artec Spider, Artec Group, Luxembourg), are provided in formats that can be opened in both open-source and commercial software, and can be readily downloaded either via an online data repository (MorphoSource) or via direct request from the DNMNH. In addition to providing surface meshes for each specimen, we also provide tomographic data (both computerized tomography [CT] and microfocus [microCT]) for a subset of these fossil specimens. This archive of the DNMNH Plio-Pleistocene collections represents the first research-quality 3D datasets of African mammal fossils to be made openly available. This simultaneously provides the paleontological community with essential baseline information (e.g., updated listing and 3D record of specimens in their current state of preservation) and serves as a single resource of high

Upper Proterozoic (1800-570 Ma) stratigraphy: a survey of lithostratigraphic, paleontological, radiochronological and magnetic correlations

International Nuclear Information System (INIS)

Trompette, R.

1982-01-01

Classical stratigraphy which was conceived in relation to the Phanerozoic, can be extended into the Precambrian, particularly the upper part. Stromatolite biostratigraphy provides natural subdivisions of the Upper Proterozoic, as indicated by studies on the Riphean of the U.S.S.R. The correlation techniques are identical to those used in the Phanerozoic. Imperfections in the biostratigraphic record, however, have encouraged the development of lithostratigraphic, radiochronological and paleomagnetic techniques. The possibility of dating argillaceous sedimentary rocks largely depends on the care taken in the selection of samples. The samples should have the necessary mineralogy and should not contain inherited 40 Ar or 87 Sr. Good results have been obtained on glauconites rich in K 2 O and particularly on illite and smectite, using the Rb-Sr method. Geochronology is the most precise of the four methods of correlation considered. It also provides a framework on which to hang the results of lithostratigraphy and magnetostratigraphy. (Auth.)

Task 50 - deposition of lignites in the Fort Union Group and related strata of the northern Great Plains

Energy Technology Data Exchange (ETDEWEB)

Hartman, J.H.; Roth, B.; Kihm, A.J.

1997-08-11

Late Cretaceous, Paleocene, and early Eocene geologic and paleontologic studies were undertaken in western North Dakota, eastern and south-central Montana, and northwestern and northeastern Wyoming. These study areas comprise the Williston, Bighorn, and Powder River Basins, all of which contain significant lignite resources. Research was undertaken in these basins because they have the best geologic sections and fossil record for the development of a chronostratigraphic (time-rock) framework for the correlation of lignite beds and other economic resources. A thorough understanding of the precise geologic age of the deposition of sediments permits a powerful means of interpreting the record of geologic events across the northern Great Plains. Such an understanding allows for rigorous interpretation of paleoenviromnents and estimates of resource potential and quality in this area of economically significant deposits. This work is part of ongoing research to document change in the composition of molluscan fossil faunas to provide a paleoenvironmentally sensitive independent means of interpreting time intervals of brief duration during the Late Cretaceous, Paleocene, and Eocene. This study focuses on the record of mollusks and, to a lesser extent, mammals in the (1) Hell Creek-Tullock Formations, which include the Cretaceous-Paleocene boundary, in the western portion of the Williston Basin, Montana; (2) uppermost Cretaceous, Paleocene, and lowermost Eocene strata in western North Dakota, which -includes the last interior seaway in North Dakota; (3) upper Paleocene and lowermost Eocene of the northern portion of the Bighorn Basin of south-central Montana and northwestern Wyoming; and (4) Powder River Basin of northeastern Wyoming and southeastern Montana. The geologic record provides different physical and paleontological information to aid in interpreting the geologic record through the study interval.

Phylogeography of screaming hairy armadillo Chaetophractus vellerosus: Successive disjunctions and extinctions due to cyclical climatic changes in southern South America.

Directory of Open Access Journals (Sweden)

Sebastián Poljak

Full Text Available Little is known about phylogeography of armadillo species native to southern South America. In this study we describe the phylogeography of the screaming hairy armadillo Chaetophractus vellerosus, discuss previous hypothesis about the origin of its disjunct distribution and propose an alternative one, based on novel information on genetic variability. Variation of partial sequences of mitochondrial DNA Control Region (CR from 73 individuals from 23 localities were analyzed to carry out a phylogeographic analysis using neutrality tests, mismatch distribution, median-joining (MJ network and paleontological records. We found 17 polymorphic sites resulting in 15 haplotypes. Two new geographic records that expand known distribution of the species are presented; one of them links the distributions of recently synonimized species C. nationi and C. vellerosus. Screaming hairy armadillo phylogeographic pattern can be addressed as category V of Avise: common widespread linages plus closely related lineages confined to one or a few nearby locales each. The older linages are distributed in the north-central area of the species distribution range in Argentina (i.e. ancestral area of distribution. C. vellerosus seems to be a low vagility species that expanded, and probably is expanding, its distribution range while presents signs of genetic structuring in central areas. To explain the disjunct distribution, a hypothesis of extinction of the species in intermediate areas due to quaternary climatic shift to more humid conditions was proposed. We offer an alternative explanation: long distance colonization, based on null genetic variability, paleontological record and evidence of alternance of cold/arid and temperate/humid climatic periods during the last million years in southern South America.

High-resolution stratigraphy with strontium isotopes.

Science.gov (United States)

Depaolo, D J; Ingram, B L

1985-02-22

The isotopic ratio of strontium-87 to strontium-86 shows no detectable variation in present-day ocean water but changes slowly over millions of years. The strontium contained in carbonate shells of marine organisms records the ratio of strontium-87 to strontium-86 of the oceans at the time that the shells form. Sedimentary rocks composed of accumulated fossil carbonate shells can be dated and correlated with the use of high precision measurements of the ratio of strontium-87 to strontium-86 with a resolution that is similar to that of other techniques used in age correlation. This method may prove valuable for many geological, paleontological, paleooceanographic, and geochemical problems.

The autonomy of the University and political intervention in the trajectories of leadership and academics groups in Natural Science of The Universidad Nacional de La Plata. 1930-1955

Directory of Open Access Journals (Sweden)

Germán Flavio Soprano Manzo

2009-11-01

Full Text Available This article analyze two process connect in one university institution. In the first part, study the autonomy's forms of the institutional organization discipline produced for the professors and investigators of the Institute of the Museum and the Superior School/ Faculty of the Natural Sciences in the Universidad Nacional de La Plata between 1935 and 1946. In the second part, study two social situations - the university interventions of the years 1946 and 1955- where the political of the National State produced changes in the trajectories of this academics. We explore this relationship in the leadership and academics groups in geology, paleontology, zoology, botanic and anthropology.

Biodiversity and Topographic Complexity: Modern and Geohistorical Perspectives

Science.gov (United States)

Badgley, Catherine; Smiley, Tara M.; Terry, Rebecca; Davis, Edward B.; DeSantis, Larisa R.G.; Fox, David L.; Hopkins, Samantha S.B.; Jezkova, Tereza; Matocq, Marjorie D.; Matzke, Nick; McGuire, Jenny L.; Mulch, Andreas; Riddle, Brett R.; Roth, V. Louise; Samuels, Joshua X.; Strömberg, Caroline A.E.; Yanites, Brian J.

2018-01-01

Topographically complex regions on land and in the oceans feature hotspots of biodiversity that reflect geological influences on ecological and evolutionary processes. Over geologic time, topographic diversity gradients wax and wane over millions of years, tracking tectonic or climatic history. Topographic diversity gradients from the present day and the past can result from the generation of species by vicariance or from the accumulation of species from dispersal into a region with strong environmental gradients. Biological and geological approaches must be integrated to test alternative models of diversification along topographic gradients. Reciprocal illumination among phylogenetic, phylogeographic, ecological, paleontological, tectonic, and climatic perspectives is an emerging frontier of biogeographic research. PMID:28196688

The geological, isotopic, botanical, invertebrate, and lower vertebrate contexts for aripithecus ramidus

Energy Technology Data Exchange (ETDEWEB)

Woldegabriel, Giday [Los Alamos National Laboratory; Ambrose, Stanley H [UNIV OF ILLINOIS; Barboni, Doris [CEREGE, FRANCE; Bonneffille, Raymond [CEREGE, FRANCE; Bremond, Laurent [MONTPELLIER, FRANCE; Currie, Brian [MIAMI UNIV, OXFORD, OHIO; Degusta, David [STANFORD UNIV.; Hart, William K [MIAMI UNIV, OXFORD, OHIO; Murray, Alison M [UNIV OF ALBERTA; Renne, Paul R [UC/BERKELEY; Jolly - Saad, M C [NANTERRE, FRANCE; Stewart, Kathlyn M [CANADA; White, Tim D [UC/BERKELEY

2009-01-01

Sediments containing Ardipithecus ramidus were deposited 4.4 million years ago on an alluvial floodplain in Ethiopia's western Afar rift. The Lower Aramis Member hominid-bearing unit, now exposed across a >9-kilometer structural arc, is sandwiched between two volcanic tuffs that have nearly identical {sup 40}Ar/{sup 39}Ar ages. Geological data presented here, along with floral, invertebrate, and vertebrate paleontological and taphonomic evidence associated with the hominids, suggest that they occupied a wooded biotope over the western three-fourths of the paleotransect. Phytoliths and oxygen and carbon stable isotopes of pedogenic carbonates provide evidence of humid cool woodlands with a grassy substrate.

Neutron Imaging in Cultural Heritage Research at the FRM II Reactor of the Heinz Maier-Leibnitz Center

Directory of Open Access Journals (Sweden)

Burkhard Schillinger

2018-01-01

Full Text Available Neutron Imaging is ideally suited for applications in cultural heritage even at small reactors with moderate image resolution. However, recently, high resolution imaging is being increasingly used for advanced studies, especially in paleontology. The special contrast for hydrogen and between neighboring elements in the periodic system allows for new applications that are not accessible for X-rays, like organic material in enclosed containers made of ceramics or metals, fossilized bones in chalk rock or in ferrous “red” beds, and even for animal and hominid teeth. Fission neutrons permit the examination of large samples that otherwise show large attenuation for thermal neutrons.

Elementos para una filogeografía de la cabra montés ibérica (Capra pyrenaica schinz, 1838

Directory of Open Access Journals (Sweden)

García-González, Ricardo

2011-12-01

Full Text Available In order to provide some issues for a future study of Capra pyrenaica phylogeography I review classic and recent works considering data of genetic studies known to date, as well as recent findings related to paleontology and biometrics. C. pyrenaica has experienced several population bottlenecks throughout its history that have led to a loss of genetic diversity. In addition, numerous recent translocations and population reinforcements can complicate the clarification of intraspecific genetic differentiation. I review current theories about the evolution of the species. One of them establishes a recent evolution (past 18,000 years from ancestors related to C. caucasica. I analyze in some detail the morphological characters (mainly teeth and horns on which this theory is based, showing their high variability. Present genetic studies show a clear relationship between C. pyrenaica and Alpine ibex (C. i. ibex. They also show a north-south genetic differentiation between Iberian goats, occupying the Pyrenean goats (C. p. pyrenaica an intermediate position between Alpine ibex and southern Iberian goats. Recent paleontological findings evidence an ancient presence (Lower Pleistocene of Capra in the Iberian Peninsula. I propose the hypothesis that the descendants of these ancient goats, may have come into contact with C. ibex in the Pyrenees and southern France, one or more times during the Upper Pleistocene. Intermediate characteristics, both genetic and biometric, of the extinct Pyrenean goats, would agree with this hypothesis. New paleontological records and more genetic studies (including fossil and recent materials are necessary, to elucidate both the phylogeny of C. pyrenaica and its intraspecific diversification.En este trabajo se realiza una revisión sintética de los trabajos clásicos y recientes que conciernen a la filogeografía de Capra pyrenaica, aportando datos de los estudios genéticos conocidos hasta la fecha, así como de nuevos

Hans-Peter Schultze, a great paleoichthyologist for whom work is synonymous with enjoyment

Directory of Open Access Journals (Sweden)

R. Cloutier

2002-01-01

Full Text Available In the summer of 1982, Hans-Peter Schultze and Gloria Arratia were invited to a small museum located on a fossiliferous site of the Devonian Escuminac Formation in Miguasha, Quebec, eastern Canada, Hans-Peter was to work with Marius Arsenault, the director of the Miguasha Museum, on the skull of the elpistostegalid Elpistostege watsoni, a species closely related to basal tetrapod. In addition, he went through the collections to describe and measure numerous juvenile specimens of the osteolepiform. Eusthenopteran foordi. As expected, there two projects turned out to be important contributions in lower vertebrate paleontology and systematics: one on the origin of tetrapods (1985, and the second one on growth patterns of a Late Devonian fish (1984. During his visit to Miguasha, Hans-Peter also spent time digging for fossils and drawing numerous specimens in the collection. In addition, in order to help the personnel of the museum to identify some of the Escuminac fished, he created an identification key based on the gross morphology of the scales. For a small group of undergraduate students, hired at the museum during the summer as naturalists, it was a unique opportunity to discuss paleontology with a leading researcher. We were amazed by his willingness to talk to us, even if then most of us only spoke French! For the first time, we were exposed to Hennigian methodology and its usage in vertebrate paleontology during and evening lecture that Hans-Peter prepared for us. His lecture was delightful; it was an intensive course in lower vertebrate anatomy, and an intellectual journey among the philosophers Karl Marx and Karl Popper, the entomologists Willy Hennig and Lars Brundin, and "The Band of Four" (Rosen et al., 1981. It was for most of us our first exposure to science, as it should be done. We were all impressed by his knowledge and above all by his simplicity and friendliness. Two years later I started my Ph.D. at The University of Kansas

First known feeding trace of the eocene bottom-dwelling fish Notogoneus osculus and its paleontological significance.

Directory of Open Access Journals (Sweden)

Anthony J Martin

Full Text Available BACKGROUND: The Green River Formation (early Eocene, about 42-53 Ma at and near Fossil Butte National Monument in Wyoming, USA, is world famous for its exquisitely preserved freshwater teleost fish in the former Fossil Lake. Nonetheless, trace fossils attributed to fish interacting with the lake bottom are apparently rare, and have not been associated directly with any fish species. Here we interpret the first known feeding and swimming trace fossil of the teleost Notogoneus osculus Cope (Teleostei: Gonorynchidae, which is also represented as a body fossil in the same stratum. METHODOLOGY/PRINCIPAL FINDINGS: A standard description of the trace fossil, identified as Undichna cf. U. simplicatas, was augmented by high-resolution digital images and spatial and mathematical analyses, which allowed for detailed interpretations of the anatomy, swimming mode, feeding behavior, and body size of the tracemaker. Our analysis indicates that the tracemaker was about 45 cm long; used its caudal, anal, and pelvic fins (the posterior half of its body to make the swimming traces; and used a ventrally oriented mouth to make overlapping feeding marks. We hypothesize that the tracemaker was an adult Notogoneus osculus. CONCLUSIONS/SIGNIFICANCE: Our results are the first to link a specific teleost tracemaker with a trace fossil from the Green River Formation, while also interpreting the size and relative age of the tracemaker. The normal feeding and swimming behaviors indicated by the trace fossil indicate temporarily oxygenated benthic conditions in the deepest part of Fossil Lake, counter to most paleoecological interpretations of this deposit. Lastly, our spatial and mathematical analyses significantly update and advance previous approaches to the study of teleost trace fossils.

The genesis and environ-mental significance of redand black sedimentaryinterlayers in coral reef of well Nanyong 2

Institute of Scientific and Technical Information of China (English)

无

2002-01-01

The results of paleogeomagnetics and geochemistry of the coral reef in well Nanyong 2 of Nansha Islands showed that the bottom of the black sedimentary interlayer corresponds to the conversion boundary line between Brunhes Postive Polarity and Matuyama Reversed Polarity (B/M) and the cold/warm (19/20) climatic conversion bounds on δ18O curve, 0.78 Ma ago; and the red sedimentary interlayer corresponds to the Reunion Ⅰ polarity excursion (reversion) of the geomagnetic field, 2.01-2.04 Ma ago. Comparing with the normal llght-coloured coral reef rock, the magnetic susceptibility (X), residual magnetization intensity (Mr) and the content of MnO and Fe2O3 of the black sedimentary layer appeared obviously positive abnormity. The magnetic susceptibility (x), residual magnetization intensity (Mr) and the content of Fe2O3 of the red sedimentary layer also appeared positive abnormity. Combining with the analyzing results of paleontology, we hold that this pair of special and typical sedimentary interlayers was relative to the sudden change of paleoclimate, i.e. the global climatic change and its incidental polarity reversal of the geomagnetic field directly affected the living environment of the paleontological species as well as the dispersion and enrichment of some chemical elements, especially the elements sensitive to redox such as Fe and Mn. For example, the elements Fe and Mn concentrated in the glacial period would be largely oxidized and diluted when the climate warmed up suddenly, and the originally oxidized high valence Fe would be condensed again when the climate cooled suddenly. This is possibly one of the important reasons of appearing and disappearing of the red and black sedimentary events of coral reef in well Nanyong 2.

Age, origins and extinctions of the avifauna of Macaronesia: a synthesis of phylogenetic and fossil information

Science.gov (United States)

Illera, Juan Carlos; Rando, Juan Carlos; Richardson, David S.; Emerson, Brent C.

2012-09-01

Understanding the age, origins and extinction of oceanic island biota has captivated the interest of evolutionary biologists since Darwin and Wallace. Because oceanic islands are discrete entities of small geographical size but with considerable habitat diversity, they provide ideal templates within which to study evolutionary processes. The peripheral North Atlantic islands, collectively referred to as Macaronesia, are considered a hot spot of biodiversity due to the fact that they contain a large proportion of endemic taxa (ca 25%). Recent molecular studies are providing insight into the patterns of colonization and radiation within the extant avifauna, while paleontological studies have described many extinct avian species, sometimes identifying the causes and chronology of extinction. The aim of this review is to develop an understanding of the evolutionary and biogeographic history of the macaronesian avifauna, combining information from phylogenetic and paleontological studies. We then compare patterns for Macaronesia with those of other oceanic archipelagos to evaluate to what extent patterns may be generalised across regions. Phylogenetic analyses have confirmed the close relationships between endemic macaronesian avifauna and the closest mainland areas (Europe and Africa), however, in contrast to other archipelagos of a similar age, we show that most extant birds appear to have colonized macaronesian archipelagos relatively recently, within the last four million years, despite some islands being approximately 30 million years old. Fossil records support the idea that higher species richness previously existed, with recent dating on bone collagen of selected extinct species suggesting that their extinction coincided with the arrival of aboriginal people ca 2500 years ago in the Canary Islands, or the arrival of Europeans across all the macaronesian islands in the 14th century. It is plausible that these human mediated extinctions may have selectively acted

Fossil struthionid eggshells from Laetoli, Tanzania: Taxonomic and biostratigraphic significance

Science.gov (United States)

Harrison, Terry; Msuya, Charles P.

2005-04-01

Recent paleontological investigations at Laetoli and neighboring localities in northern Tanzania have produced a large collection of fossil ostrich eggshells from the Pliocene-aged Laetolil Beds (˜3.5-4.5 Ma) and Ndolanya Beds (˜2.6-2.7 Ma). A detailed analysis of the morphology of the eggshells and their taxonomic affinities indicates that two different species of Struthio are represented. In the Lower Laetolil Beds and in the Upper Laetolil Beds below Tuff 3 a new species is recognized— Struthio kakesiensis. This is replaced in the Upper Laetolil Beds by Struthio camelus, the modern species of ostrich. Since radiometric age determinations are available for the stratigraphic sequence at Laetoli, it is possible to precisely date the first appearance of S. camelus at ˜3.6-3.8 Ma. Comparisons of the Laetoli material with specimens from the well-dated sequences at Lothagam and Kanapoi in northern Kenya, allow the taxonomic and biochronological analysis to be extended back in time to the late Miocene. At about 6.5 Ma, Diamantornis and elephant birds were replaced in East Africa by ostriches belonging to the genus Struthio. Three time-successive species of ostriches are identified in the fossil record of East Africa, beginning with Struthio. cf. karingarabensis (˜6.5-4.2 Ma), followed by S. kakesiensis (˜4.5-3.6 Ma) and then S. camelus (˜3.8 Ma onwards). A similar sequence of taxa has previously been recorded from localities in Namibia, but at these sites there is no possibility to precisely calibrate the ages of the different species using radiometric dating. Nevertheless, the broadly similar evolutionary sequence and the close correspondence in inferred ages for the succession of species in East Africa and Namibia suggest that ostrich eggshells are a very useful tool for biochronological correlation of paleontological sites in sub-Saharan Africa.

Robust time estimation reconciles views of the antiquity of placental mammals.

Directory of Open Access Journals (Sweden)

Yasuhiro Kitazoe

2007-04-01

Full Text Available Molecular studies have reported divergence times of modern placental orders long before the Cretaceous-Tertiary boundary and far older than paleontological data. However, this discrepancy may not be real, but rather appear because of the violation of implicit assumptions in the estimation procedures, such as non-gradual change of evolutionary rate and failure to correct for convergent evolution.New procedures for divergence-time estimation robust to abrupt changes in the rate of molecular evolution are described. We used a variant of the multidimensional vector space (MVS procedure to take account of possible convergent evolution. Numerical simulations of abrupt rate change and convergent evolution showed good performance of the new procedures in contrast to current methods. Application to complete mitochondrial genomes identified marked rate accelerations and decelerations, which are not obtained with current methods. The root of placental mammals is estimated to be approximately 18 million years more recent than when assuming a log Brownian motion model. Correcting the pairwise distances for convergent evolution using MVS lowers the age of the root about another 20 million years compared to using standard maximum likelihood tree branch lengths. These two procedures combined revise the root time of placental mammals from around 122 million years ago to close to 84 million years ago. As a result, the estimated distribution of molecular divergence times is broadly consistent with quantitative analysis of the North American fossil record and traditional morphological views.By including the dual effects of abrupt rate change and directly accounting for convergent evolution at the molecular level, these estimates provide congruence between the molecular results, paleontological analyses and morphological expectations. The programs developed here are provided along with sample data that reproduce the results of this study and are especially

ASSESSING THE INFLUENCE OF THE SOLAR ORBIT ON TERRESTRIAL BIODIVERSITY

International Nuclear Information System (INIS)

Feng, F.; Bailer-Jones, C. A. L.

2013-01-01

The terrestrial record shows a significant variation in the extinction and origination rates of species during the past half-billion years. Numerous studies have claimed an association between this variation and the motion of the Sun around the Galaxy, invoking the modulation of cosmic rays, gamma rays, and comet impact frequency as a cause of this biodiversity variation. However, some of these studies exhibit methodological problems, or were based on coarse assumptions (such as a strict periodicity of the solar orbit). Here we investigate this link in more detail, using a model of the Galaxy to reconstruct the solar orbit and thus a predictive model of the temporal variation of the extinction rate due to astronomical mechanisms. We compare these predictions as well as those of various reference models with paleontological data. Our approach involves Bayesian model comparison, which takes into account the uncertainties in the paleontological data as well as the distribution of solar orbits consistent with the uncertainties in the astronomical data. We find that various versions of the orbital model are not favored beyond simpler reference models. In particular, the distribution of mass extinction events can be explained just as well by a uniform random distribution as by any other model tested. Although our negative results on the orbital model are robust to changes in the Galaxy model, the Sun's coordinates, and the errors in the data, we also find that it would be very difficult to positively identify the orbital model even if it were the true one. (In contrast, we do find evidence against simpler periodic models.) Thus, while we cannot rule out there being some connection between solar motion and biodiversity variations on the Earth, we conclude that it is difficult to give convincing positive conclusions of such a connection using current data.

Geologic literature on North America, 1785-1918; Part I, Bibliography

Science.gov (United States)

Nickles, John M.

1923-01-01

The bibliography forming Part I of this compilation includes papers relating to the geology paleontology, petrology, and mineralogy of North America-specifically, the United States, the Dominion of Canada and Newfoundland, the Arctic regions north of the continent, Greenland, Mexico Central America, Panama, and the West Indies including Trinidad-and also the Hawaiian Islands. Geographic and descriptive writings and accounts of travels with incidental mention of geologic facts are not included. Textbooks published in America and work general in character by American authors are given but general papers by foreign writers are excluded unless they have appeared in American publications. Papers by American writers on the geology of other parts of the world are not listed.

Morfologia de Osteodermos de Crocodilomorfos do Sítio Paleontológico de Peirópolis (Bacia Bauru, Cretáceo Superior.

Directory of Open Access Journals (Sweden)

Thiago da Silva Marinho

2006-07-01

Full Text Available Osteoderms are dermal bony plates situated over the epiderm andcovered by queratin layer. Until now are recognized at the Paleontological Site of Peirópolis three distinct crocodylomorph species, the Peirosauridae Peirosaurus termini Price, 1955 and Uberabasuchus terrificus Carvalho; Ribeiro & Ávilla, 2004 and the Trematochampsidae Itasuchus jesuinoi Price, 1955. The peirosaurids have nostrils frontally positioned within the skull and are regarded as terrestrial crocodylomorphs. The trematochampsids differentlyfrom the peirosaurids have the nostrils positioned at the dorsal portion of the skull, similar to the extant crocodiles with aquatic habits. The osteoderms morphological analysis of P. tormini, U. terrificus and I. jesuinoi corroborate, with the cranial evidences, for the terrestrial or aquatic lifestyle of these animals.

How long ago did smallpox virus emerge?

Science.gov (United States)

Shchelkunov, Sergei N

2009-01-01

Unlike vertebrates, for which paleontological data are available, and RNA viruses, which display a high rate of genetic variation, an objective estimate of time parameters for the molecular evolution of DNA viruses, which display a low rate of accumulation of mutations, is a complex problem. Genomic studies of a set of smallpox (variola) virus (VARV) isolates demonstrated the patterns of phylogenetic relationships between geographic variants of this virus. Using archival data on smallpox outbreaks and the results of phylogenetic analyses of poxvirus genomes, different research teams have obtained contradictory data on the possible time point of VARV origin. I discuss the approaches used for dating of VARV evolution and adduce the arguments favoring its historically recent origin.

Cultural resources: Deaf Smith and Swisher County locations, Palo Duro Basin, Texas

International Nuclear Information System (INIS)

1984-12-01

Cultural resources are prehistoric and historic sites, including archeological and paleontological sites, that are important to a group of people. They are protected by both federal and state legislation. In the area covered by the Deaf Smith and Swisher County locations, four stages of cultural development have been identified: Paleo-Indian, Archaic, Ceramic (Neo-Indian or Neo-American), and Historic. Areas where undiscovered cultural resources are most likely to be found include sources of water, playa lakes, and historic trails. Because extensive surveying has not been done in either location, the number of identified sites is low. However, the potential for finding undiscovered sites is high for significant parts of both locations

U/Pb dating: brioverian age of the Erquy series (Armorican massif, France)

International Nuclear Information System (INIS)

Cocherie, A.; Chantraine, J.; Egal, E.; Fanning, C.M.; Dabard, M.P.; Paris, F.; Le Herisse, A.

2001-01-01

New U/Pb analyses obtained with a high-resolution ion microprobe (SHRIMP) fix an age of 608 ± 7 Ma for spilites of the Erquy series, in Cadomian rocks of the Armorican massif, France. This Neo-proterozoic age re-integrates this unit into the Brioverian, the age it was initially assigned to. A Rb/sr whole-rock dating in the 1970's had undermined the regional Cadomian model, by suggesting an Ordovician age for these rocks; this was apparently further supported by the discovery of organic remains, interpreted as Paleozoic micro-fossils. The reassessment of this paleontologic attribution and the new isotope dating are a final confirmation of the age of this series. (authors)

Biodiversity and Topographic Complexity: Modern and Geohistorical Perspectives.

Science.gov (United States)

Badgley, Catherine; Smiley, Tara M; Terry, Rebecca; Davis, Edward B; DeSantis, Larisa R G; Fox, David L; Hopkins, Samantha S B; Jezkova, Tereza; Matocq, Marjorie D; Matzke, Nick; McGuire, Jenny L; Mulch, Andreas; Riddle, Brett R; Roth, V Louise; Samuels, Joshua X; Strömberg, Caroline A E; Yanites, Brian J

2017-03-01

Topographically complex regions on land and in the oceans feature hotspots of biodiversity that reflect geological influences on ecological and evolutionary processes. Over geologic time, topographic diversity gradients wax and wane over millions of years, tracking tectonic or climatic history. Topographic diversity gradients from the present day and the past can result from the generation of species by vicariance or from the accumulation of species from dispersal into a region with strong environmental gradients. Biological and geological approaches must be integrated to test alternative models of diversification along topographic gradients. Reciprocal illumination among phylogenetic, phylogeographic, ecological, paleontological, tectonic, and climatic perspectives is an emerging frontier of biogeographic research. Copyright © 2017 Elsevier Ltd. All rights reserved.

Abstracts of the GAC-MAC annual meeting : for a change of climate

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-07-01

This joint meeting of the Geological Association of Canada and the Mineralogical Association of Canada provided a forum to discuss a broad range of issues dealing with geosciences and resource exploration. Topics of discussion included economic geology; structural geology and tectonics; mineralogy, crystallography and mineral chemistry; igneous petrology, volcanology and metamorphic petrology; and, sedimentology, paleontology and micropaleontology. New tools and technologies for mineral exploration were highlighted. Specialists in Earth sciences from Canada, the United States and Europe participated in the general session as well as conference exhibits, symposia, special courses, workshops, poster sessions, field trips and an outreach program. The conference featured more than 150 presentations, of which 8 have been catalogued separately for inclusion in this database.

Spicules of Litistidic sponges from the upper Eocene Verhivtsevska depression (Miiddle Dniprean

Directory of Open Access Journals (Sweden)

Ivanova T.A.

2014-12-01

Full Text Available For the first time a taxonomic composition of lithistid sponges which are lived in the Late Eocene basin of Verchovtzev depression Ukrainian Shield is supposed by the spicules morphological analysis. There are sponges of ten geneses and seven families presented in paleocoenosis, but families Theonellidae (geneses Lerouxia, Rhagadinia andPlinthosellidae (genusPlinthosella are dominated. Threenewmorphospeciesof spicules aredescribed: Phyllotriaenapartita T.A.Ivanova morphosp.n., Ph. araneola T.A.Ivanova, morphosp.n., Tetracrepides semiornatus T.A.Ivanova, morphosp.n. Their stratigraphical meaning is determined. These spicules are characteristic for the Obuchovian Suite and would be used as the paleontological criterion of the Obuchovian Suite determination in geological sections of the Middle Dnieper region.

Morphogenesis and pattern formation in biological systems experiments and models

CERN Document Server

Noji, Sumihare; Ueno, Naoto; Maini, Philip

2003-01-01

A central goal of current biology is to decode the mechanisms that underlie the processes of morphogenesis and pattern formation. Concerned with the analysis of those phenomena, this book covers a broad range of research fields, including developmental biology, molecular biology, plant morphogenesis, ecology, epidemiology, medicine, paleontology, evolutionary biology, mathematical biology, and computational biology. In Morphogenesis and Pattern Formation in Biological Systems: Experiments and Models, experimental and theoretical aspects of biology are integrated for the construction and investigation of models of complex processes. This collection of articles on the latest advances by leading researchers not only brings together work from a wide spectrum of disciplines, but also provides a stepping-stone to the creation of new areas of discovery.

Ust-Ishim Bone: Mineralogical and Geochemical Characteristics as the Source of the Paleontological, Paleoecological, and Paleoanthropological Information

Directory of Open Access Journals (Sweden)

V. I. Silaev

2017-03-01

Full Text Available Ust-Ishim man was the representative of one of the ancestral groups of the Homo sapiens, Neanderthals and Denisovans. The first results of a comprehensive mineralogical and geochemical study of fossil bones using a wide range of physical, chemical and physico-chemical methods: thermal analysis, optical microscopy, scanning electron microscopy, atomic-force microscopy, nitrogen capillary condensation method, X-ray fluorescence analysis, ISP-MS, gas chromatography method, amino acid chromatography analysis’s, X-ray microprobe method, X-ray diffraction method, Raman and infrared spectroscopy, isotope spectrometry are presented in this article. The studied fragment of the skeleton is of higher preservation rate than the common bone detritus of this age and even the fossils of younger Pleistocene animals that allowed determining almost all its primary properties. The unique preservation presumably was provided by the favorable environment and a special way the Ust-Ishim man originally was buried. Results of study of the chemical and mineral composition of the bone fossils allowed a reconstruction of the Ust-Ishim man life history.

Including autapomorphies is important for paleontological tip-dating with clocklike data, but not with non-clock data.

Science.gov (United States)

Matzke, Nicholas J; Irmis, Randall B

2018-01-01

Tip-dating, where fossils are included as dated terminal taxa in Bayesian dating inference, is an increasingly popular method. Data for these studies often come from morphological character matrices originally developed for non-dated, and usually parsimony, analyses. In parsimony, only shared derived characters (synapomorphies) provide grouping information, so many character matrices have an ascertainment bias: they omit autapomorphies (unique derived character states), which are considered uninformative. There has been no study of the effect of this ascertainment bias in tip-dating, but autapomorphies can be informative in model-based inference. We expected that excluding autapomorphies would shorten the morphological branchlengths of terminal branches, and thus bias downwards the time branchlengths inferred in tip-dating. We tested for this effect using a matrix for Carboniferous-Permian eureptiles where all autapomorphies had been deliberately coded. Surprisingly, date estimates are virtually unchanged when autapomorphies are excluded, although we find large changes in morphological rate estimates and small effects on topological and dating confidence. We hypothesized that the puzzling lack of effect on dating was caused by the non-clock nature of the eureptile data. We confirm this explanation by simulating strict clock and non-clock datasets, showing that autapomorphy exclusion biases dating only for the clocklike case. A theoretical solution to ascertainment bias is computing the ascertainment bias correction (M k parsinf ), but we explore this correction in detail, and show that it is computationally impractical for typical datasets with many character states and taxa. Therefore we recommend that palaeontologists collect autapomorphies whenever possible when assembling character matrices.

A Literature Review of Archaeological, Historical, and Paleontological Resources of the Sheyenne River Basin in North Dakota

Science.gov (United States)

1977-01-01

description of the Red River valley area was derived from Shay (1967: 231-237) and Scoby et. al. (1973). The Red River valley per se is flat except where...it is inter- rupted by the Sheyenne delta escarpment and the glacial Lake Agassiz shorelines ( Scoby et. al. 1973: 16). Surface drainage in the area is...very poor with runoff tending to collect in low lying areas ( Scoby et. al. 1973: 23). Prior to inten- sive drainage the area may have possessed many

Mid-infrared spectroscopy for characterization of Baltic amber (succinite)

Science.gov (United States)

Wagner-Wysiecka, Ewa

2018-05-01

Natural Baltic amber (succinite) is the most appreciated fossil resin of the rich cultural traditions dating back to prehistoric times. Its unequivocal identification is extremely important in many branches of science and trades including archeology, paleontology, chemistry and finally mineralogical and gemological societies. Current methods of modification of natural succinite are more and more sophisticated making the identification of natural Baltic amber often challenging. In article the systematic analytical approach for identification of natural and modified under different conditions succinite, using mid-infrared spectroscopy (transmission, Drifts and ATR techniques) is presented. The correlation between spectral characteristics and properties of succinite is discussed pointing that the understanding of the nature of changes is the key of identification of this precious material.

Hanford Cultural Resources Laboratory annual report for fiscal year 1994

International Nuclear Information System (INIS)

Nickens, P.R.; Wright, M.K.; Cadoret, N.A.; Dawson, M.V.; Harvey, D.W.; Simpson, E.M.

1995-09-01

The Hanford Site occupies 560 sq. miles of land along the Columbia River in SE Washington. The Hanford Reach of the river is one of the most archaeologically rich areas in the western Columbia Plateau. To manage the Hanford Site's archaeological, historical, and cultural resources, the Hanford Cultural Resources Laboratory (HCRL) was established in 1987. HCRL ensures DOE complies with federal statutes, regulations, and guidelines. In FY 1994, HCRL conducted cultural resource reviews, conducted programs to identify and monitor historic and archaeological sites, etc. HCRL staff conducted 511 reviews, 29 of which required archaeological surveys and 10 of which required building documentation. Six prehistoric sites, 23 historic sites, one paleontological site, and two sites with historic and prehistoric components were discovered

The hand of birds revealed by early ostrich embryos

Science.gov (United States)

Feduccia, Alan; Nowicki, Julie

2002-08-01

The problem of resolving the homology of the digits of the avian hand has been framed as a conflict between paleontological and embryological evidence, the former thought to support a hand composed of digits I, II, III, because of similarity of the phalangeal formulae of the earliest known bird Archaeopteryx to that of Mesozoic pentadactyl archosaurs, while embryological evidence has traditionally favored a II, III, IV avian hand. We have identified the critical developmental period for the major features of the avian skeleton in a primitive bird, the ostrich. Analysis of digit anlagen in the avian hand has revealed those for digits/metacarpals I and V, thus confirming previous embryological studies that indirectly suggested that the avian hand comprises digits II, III, IV, and was primitively pentadactyl.

Petroleum resources assessment 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-01

This report consists of two articles. (1) Petroleum resources assessment of the Okinawa Trough: The hydrocarbon potential has been evaluated for the Tertiary strata in the northwestern margin of the Okinawa Trough on the basis of the pale-ontological, petrological, geochemical data from two wells (Nikkan 8-9 and JDZ 7-3), and geophysical data. (2) Petroliferous basin analysis in Jinju area (2): Petroleum geological studies such as stratigraphy, sedimentology, petrology and organic geochemistry were carried out in the Gyeongsang Supergroup, Junju area. Based on lithofacies and rock color, the sequence can be divided into seven formations which can be organized into two groups (Sindong Group: Nagdong, Hasandong and Jinju formations in ascending order; Hayang Group: Chilgog, Silla Conglomerate, Haman and Jindong formations). (author). 57 refs.

LUTETIAN LIMESTONES IN THE PARIS REGION: PETROGRAPHIC AND COMPOSITIONAL EXAMINATION

International Nuclear Information System (INIS)

BLANC, A.; HOLMES, L.L.; HARBOTTLE, G.

1998-01-01

Stone for building and decorating monuments in the Paris Basin from antiquity to the present came from numerous quarries in the Lutetian limestone formations of the region. To identify specific-stone sources used for masonry and sculptures in these monuments, a team of geologists and archaeologists has investigated 300 quarries and collected 2,300 limestone samples for study in a collaborative effort by geologists and chemists. Petrographic and paleontologic examinations of thin sections enable geologists to distinguish the Tertiary Lutetian limestones from similar stone in Jurassic and Cretaceous strata. The methods of the geologist have been supplemented by those of the chemist whose compositional studies by neutron activation analysis can differentiate among the fine-grained upper Lutetian limestones extracted from specific ancient quarries

Necrópolis Ibérica de «El Cigarralejo» : estudio osteológico (comparado con los ajuares

Directory of Open Access Journals (Sweden)

M. Santonja Alonso

1993-01-01

Full Text Available Se expone detalladamente la «historia» osteológica de 187 cremados de la Necrópolis Ibérica de «El Cigarralejo»: sexo, edad, medidas de epífisis y grosores de pared en ios fragmentos más frecuentes, paleontología que presentan, sus interrogantes y conclusiones. Igualmente, sobre la identificación de las tumbas dobles y de las infantiles.The osteologic «history» of 187 cremations from the «Necrópolis Ibérica de el Cigarralejo» is expounded in detall: sex, age, epiphysis, measurements, thickness of the most frequent pieces, and palaeopathology features, as well as some and conclusions. At the same time, it will deal with Children's and double graves Identification.

Hanford Cultural Resources Laboratory annual report for fiscal year 1994

Energy Technology Data Exchange (ETDEWEB)

Nickens, P.R.; Wright, M.K.; Cadoret, N.A.; Dawson, M.V.; Harvey, D.W.; Simpson, E.M.

1995-09-01

The Hanford Site occupies 560 sq. miles of land along the Columbia River in SE Washington. The Hanford Reach of the river is one of the most archaeologically rich areas in the western Columbia Plateau. To manage the Hanford Site`s archaeological, historical, and cultural resources, the Hanford Cultural Resources Laboratory (HCRL) was established in 1987. HCRL ensures DOE complies with federal statutes, regulations, and guidelines. In FY 1994, HCRL conducted cultural resource reviews, conducted programs to identify and monitor historic and archaeological sites, etc. HCRL staff conducted 511 reviews, 29 of which required archaeological surveys and 10 of which required building documentation. Six prehistoric sites, 23 historic sites, one paleontological site, and two sites with historic and prehistoric components were discovered.

Lithostratigraphy, sedimentology and paleography from The Arroyo del Soldado group

International Nuclear Information System (INIS)

Gaucher, C.; Sprechmann, P.; Montana, J.; Martinez, S.

1998-01-01

The lithostratigraphy of the Vendian to Lower Cambrian Arroyo del Soldado Group of the Nico Perez Terrane is presented. The Yerbal Formation is defined and the Barriga Negra Formation is included in the Group. The Arroyo del Soldado Group represents a transgressive - regressive sequence developed on a passive continental margin, reaching a thickness of 5000m. The lithofacies succession is mainly explained by the combination of tectonic processes, global climatic - and sea level changes. Its geographic extension allows the determination of the eastern and southern boundaries of the Nico Perez Terrane. The known surface of this Terrane is therefore considerably increased. Several outcroups previously assigned to the Lavalleja Group are in this paper included in the Arroyo del Soldado Group, using sedimentalogical and paleontological criteria

X-ray computed tomography datasets for forensic analysis of vertebrate fossils

Science.gov (United States)

Rowe, Timothy B.; Luo, Zhe-Xi; Ketcham, Richard A.; Maisano, Jessica A.; Colbert, Matthew W.

2016-01-01

We describe X-ray computed tomography (CT) datasets from three specimens recovered from Early Cretaceous lakebeds of China that illustrate the forensic interpretation of CT imagery for paleontology. Fossil vertebrates from thinly bedded sediments often shatter upon discovery and are commonly repaired as amalgamated mosaics grouted to a solid backing slab of rock or plaster. Such methods are prone to inadvertent error and willful forgery, and once required potentially destructive methods to identify mistakes in reconstruction. CT is an efficient, nondestructive alternative that can disclose many clues about how a specimen was handled and repaired. These annotated datasets illustrate the power of CT in documenting specimen integrity and are intended as a reference in applying CT more broadly to evaluating the authenticity of comparable fossils. PMID:27272251

Abstracts of the GAC-MAC-CSPG-CSSS 2005 joint meeting : building bridges across science, through time, around the world

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

This joint meeting of the Geological Association of Canada, the Mineralogical Association of Canada, the Canadian Society of Petroleum Geologists, and the Canadian Society of Soil Science addressed many topical issues dealing with geosciences, with particular reference to resource exploration. The 7 sessions within the general session were: (1) economic geology, (2) structural geology and tectonics, (3) mineralogy, crystallography and crystal chemistry, (4) igneous petrology, volcanology and metamorphic petrology, (5) sedimentology, paleontology and micropaleontology, (6) geophysics, and (7) soil science. In addition to the general session, the conference included exhibits, symposia, special courses, workshops, poster sessions, field trips and an outreach program. The conference featured approximately 80 presentations, of which 45 have been catalogued separately for inclusion in this database.

Abstracts of the GAC-MAC-CSPG-CSSS 2005 joint meeting : building bridges across science, through time, around the world

International Nuclear Information System (INIS)

2005-01-01

This joint meeting of the Geological Association of Canada, the Mineralogical Association of Canada, the Canadian Society of Petroleum Geologists, and the Canadian Society of Soil Science addressed many topical issues dealing with geosciences, with particular reference to resource exploration. The 7 sessions within the general session were: (1) economic geology, (2) structural geology and tectonics, (3) mineralogy, crystallography and crystal chemistry, (4) igneous petrology, volcanology and metamorphic petrology, (5) sedimentology, paleontology and micropaleontology, (6) geophysics, and (7) soil science. In addition to the general session, the conference included exhibits, symposia, special courses, workshops, poster sessions, field trips and an outreach program. The conference featured approximately 80 presentations, of which 45 have been catalogued separately for inclusion in this database. (author)

Characterization of a branch of the phylogenetic tree

International Nuclear Information System (INIS)

Samuel, Stuart A.; Weng, Gezhi

2003-04-01

We use a combination of analytic models and computer simulations to gain insight into the dynamics of evolution. Our results suggest that certain interesting phenomena should eventually emerge from the fossil record. For example, there should be a 'tortoise and hare effect': Those genera with the smallest species death rate are likely to survive much longer than genera with large species birth and death rates. A complete characterization of the behavior of a branch of the phylogenetic tree corresponding to a genus and accurate mathematical representations of the various stages are obtained. We apply our results to address certain controversial issues that have arisen in paleontology such as the importance of punctuated equilibrium and whether unique Cambrian phyla have survived to the present

Present knowledge on the fossil mammals record from Chile; Estado actual del conocimiento de los mamiferos fosiles de Chile

Energy Technology Data Exchange (ETDEWEB)

Canto, J.; Yanez, J.; Rovira, J.

2010-07-01

An updated revision is presented regarding fossil mammals of aquatic and terrestrial environments. This update includes up to year 2008. Those registrations of doubtful assignation or that couldn't be confirmed were not considered in this review. These new registrations are classified in four groups of time that extend from the Late Eocene-Early Oligocene to the Pleistocene-Recent. The evidence shows that the greatest quantity of fossils are concentrated from the Early Miocene to the Middle Miocene reaching 37 (41.5%) genus of a total of 77 and 54 (49.5%) fossil species of a total of 89. It is observed a significant increase in works devoted to paleontology of mammal fossils in Chile between 1981-2008. (Author)

The sedimentary record of dinoflagellate cysts: looking back into the future of phytoplankton blooms

Directory of Open Access Journals (Sweden)

Barrie Dale

2001-12-01

Full Text Available Marine systems are not as well understood as terrestrial systems, and there is still a great need for more primary observations, in the tradition of the old-time naturalists, before newer methods such as molecular genetics and modeling can be fully utilized. The scientific process whereby the smaller, detailed building blocks of observation are ultimately linked towards better understanding natural systems is illustrated from my own career experience, especially with regard to the dinoflagellates and plankton blooms. Some dinoflagellates produce a fossilizable resting stage (cyst in their life cycle, and dinoflagellate cysts have become one of the most important groups of microfossils used in geological exploration (e.g. oil and gas. This has stimulated both paleontological and biological research producing detailed building blocks of information, currently scattered throughout the respective literature. Here, I attempt to bring together the present day perspective, from biology, with the past, from paleontology, as the most comprehensive basis for future work on the group. This shows the cysts to be the critical link needed for focusing future molecular genetics studies towards a more verifiable view of evolutionary pathways, and it also suggests new integrated methods for studying past, present, and future blooms. The large, rapidly growing field of harmful algal bloom studies is producing many different building blocks, but plankton blooms as episodic phenomena are still poorly understood. This is largely due to the general lack of long-term datasets allowing identification of the changing environmental factors that permit certain species to bloom at unpredictable intervals of time. Cysts in sediments are useful environmental indicators today, e.g. reflecting aspects of climate and pollution, and provide information directly relevant to some dinoflagellate blooms. They therefore may be used for obtaining retrospective information from the

Continuity or discontinuity in the European Early Pleistocene human settlement: the Atapuerca evidence

Science.gov (United States)

Bermúdez de Castro, José María; Martinón-Torres, María; Blasco, Ruth; Rosell, Jordi; Carbonell, Eudald

2013-09-01

The nature, timing, pattern, favourable circumstances and impediments of the human occupation of the European continent during the Early Pleistocene are hot topics in Quaternary studies. In particular, the problem of the (dis) continuity of the settlement of Europe in this period is an important matter of discussion, which has been approached in the last decade from different points of view. The Gran Dolina (TD) and Sima del Elefante (TE) cave sites in the Sierra de Atapuerca, (Spain) include large and quasi-continuous stratigraphic sequences that stretch back from at least 1.2 million years ago (Ma) to the Matuyama/Brunhes boundary. The archaeological and paleontological record from these sites can help to test different hypotheses about the character of the human settlement in this region and period. Furthermore, the TD6 level has yielded a large collection of human fossil remains attributed to Homo antecessor. According to different geochronological methods, as well as to paleomagnetic and biostratigraphical analyses, these hominins belong to an age range of 0.96-0.80 Ma. Unfortunately, the finding in 2007 of some human fossil remains in the TE9 level, dated to about 1.22 Ma, was not enough to conclude whether H. antecessor had deep roots in the European Early Pleistocene. A set of derived features of H. antecessor shared with both the Neanderthal lineage and modern humans suggests that this species is related, and not far, from the most recent common ancestor (MRCA) of Homo neanderthalensis and Homo sapiens. If we assume that there was a lineal biological relationship between the TE9 and TD6 hominins, we should reconsider many of the conclusions achieved in previous paleontological and genetic studies. In addition, we would be obliged to build a highly complicated paleogeographical scenario for the origin of the MRCA. Although continuity in the settlement of Europe during the entire late Early Pleistocene is not discarded (e.g. in refuge areas), it seems that

The Quequén Salado river basin: Geology and biochronostratigraphy of the Mio-Pliocene boundary in the southern Pampean plain, Argentina

Science.gov (United States)

Beilinson, E.; Gasparini, G. M.; Tomassini, R. L.; Zárate, M. A.; Deschamps, C. M.; Barendregt, R. W.; Rabassa, J.

2017-07-01

The Quequén Salado river basin has been the focus of several contributions since the first decades of the XX century, namely dealing with the general geological features of the deposits and with the vertebrate remains. In this paper, the Neogene geological history documented by the Quequén Salado river exposures is reconstructed by means of stratigraphic, sedimentological and paleomagnetic studies along with the paleontological analysis of vertebrate remains. The study area is a crucial setting not only to better understand the evolution of the southern Pampas basin during the late Miocene-early Pliocene interval, but also to test the validity of the biochronologic and biostratigraphic schemes, especially the "Irenense". A geological model for the Quequén Salado river valley is proposed: a case of downcutting and headward erosion that contributes with a coherent interpretation to explain the spatial distribution of facies and fossil taxa: the younger in the distal sector of the Quequén Salado middle basin and the older in the lower basin. The sedimentary record is believed to represent the distal reaches of a distributary fluvial system that drained from the Ventania ranges. The stratigraphic section of Paso del Indio Rico results a key stratigraphic site to fully understand the stratigraphic nature of the boundary between the Miocene and the Pliocene (the Huayquerian and Montehermosan stages/ages). In this sense, two stratigraphically superposed range zones have been recognized in the area: Xenodontomys ellipticus Range Zone (latest Miocene-early Pliocene; late Huayquerian), and Eumysops laeviplicatus Range Zone (early Pliocene; Montehermosan). Taking into account the available geological and paleontological evidences, the "Irenense" would not represent a valid biostratigraphic unit, since, according to the geological model here proposed, it would be represented by elements of the Xenodontomys ellipticus Range Zone in the lower QS basin and by elements of the

Can we avoid the Sixth Mass Extinction? Setting today's extinction crisis in the context of the Big Five

Science.gov (United States)

Barnosky, A. D.

2012-12-01

While the ultimate extinction driver now—Homo sapiens—is unique with respect to the drivers of past extinctions, comparison of parallel neontological and paleontological information helps calibrate how far the so-called Sixth Mass Extinction has progressed and whether it is inevitable. Such comparisons document that rates of extinction today are approaching or exceeding those that characterized the Big Five Mass Extinctions. Continuation of present extinction rates for vertebrates, for example, would result in 75% species loss—the minimum benchmark exhibited in the Big Five extinctions—within 3 to 22 centuries, assuming constant rates of loss and no threshold effects. Preceding and during each of the Big Five, the global ecosystem experienced major changes in climate, atmospheric chemisty, and ocean chemistry—not unlike what is being observed presently. Nevertheless, only 1-2% of well-assessed modern species have been lost over the past five centuries, still far below what characterized past mass extinctions in the strict paleontological sense. For mammals, adding in the end-Pleistocene species that died out would increase the species-loss percentage by some 5%. If threatened vertebrate species were to actually go extinct, losses would rise to between 14 and 40%, depending on the group. Such observations highlight that, although many species have already had their populations drastically reduced to near-critical levels, the Sixth Mass Extinction has not yet progressed to the point where it is unavoidable. Put another way, the vast majority of species that have occupied the world in concert with Homo sapiens are still alive and are possible to save. That task, however, will require slowing the abnormally high extinction rates that are now in progress, which in turn requires unified efforts to cap human population growth, decrease the average human footprint, reduce fossil fuel use while simultaneously increasing clean energy technologies, integrate

MUSEUM GEOLOGI DAN PRASEJARAH DI MAKASSAR DENGAN PENDEKATAN ARSITEKTUR HIGH TECH

Directory of Open Access Journals (Sweden)

Saefullah Saefullah

2015-12-01

Full Text Available Abstrak—Indonesia kaya akan sumber daya geologi yang terdiri dari batuan, mineral dan bahan tambang. Berbicara mengenai geologi sangat erat kaitannya dengan zaman prasejarah.karena belum ditemukannya bukti-bukti tertulis dari zaman prasejarah tersebut, keterangan mengenai zaman ini diperoleh melalui bidang-bidang seperti paleontologi, astronomi, biologi, geologi, antropologi, dan arkeologi pentingnya melestarikan dan menjaga peninggalan-peninggalan prasejarah. Sehingga akan menumbuhkan rasa tanggungjawab terhadapnya. Hal ini sejalan dengan tugas Direktorat Jendral Kebudayaan Kementrian Pendidikan dan Kebudyaaan Indonesia dalam laporan kinerjanya .yang mengemukakan bahwa sisa-sisa peninggalan sejarah penting dipelihara sebagai pelajaran hidup bagi generasi berikutnya.Tujuan penelitian menyusun suatu landasan konseptual desain perancangan Museum Geologi dan prasejarah dengan pendekatan arsitektur high-tech, menerapkan system Double fasade, Ligth Pipe dan system fotovoltaic pada bangunan, mengaplikasikan intelegent system pada utilitas pada bangunan.Hasil Laporan ini adalah mendesain bangunan museum geologi dan prasejarah di Makassar dengan pendekatan arsitektur high-tech. Kata Kunci :Museum geologi, prasejarah, high-tech Abstract-Indonesia is rich geological resources consisting of rocks, minerals and minerals. Talking about the geology is very closely related to prehistoric times because of not finding written evidence from prehistoric times, the information concerning this age obtained through fields like paleontology, astronomy, biology, geology, anthropology, and archeology importance of preserving and maintaining prehistoric relics. So will foster a sense of responsibility to it. This is in line with the duties of the Directorate General of Culture Ministry of Education and Indonesian culture in its performance report which suggested that the remains of important historical remains preserved as a living lesson for the next generation. The

A Science Centre as a Geoturism promoter - the Lagos Ciência Viva examples (Portugal).

Science.gov (United States)

Azevedo Rodrigues, Luis; Leote, Catarina

2017-04-01

Science outreach and engagement are crucial core objectives of the Lagos Ciência Viva Science Centre (CCVL). By engaging audiences in the real world a link is made between their science centre experience and the environment in which they live. Therefore, it has been an option of the CCVL to offer geological outdoor activities, both in the natural environment and urban context. Dinosaurs are an appealing science subject for both students and tourists. Thus, the CCVL has a long tradition in organizing and guiding field trips to two dinosaur track sites - Salema and Santa beaches (Vila do Bispo, southwest Algarve). These sites, both from the Lower Cretaceous reveal at least two types of tracks - theropod and iguanodontian footprints. Often in combination with the paleontology field trips, the CCVL also offers different geological field trips both for formal (school) and informal (tourism) education. This allows students and tourists to be introduced to dinosaur paleobiology and ichnology and to the structural geology and stratigraphy of the area. Our science outreach is being further developed by contractual agreement with a regional tour operator, in which the CCVL is responsible for the scientific content and guidance of the visits. Aiming at an urban context, the CCVL produced three Urban Geology and Paleontology Guide Books for three Algarve cities (Lagos, Faro and Tavira), which can be acquired in the three Ciência Viva Science Centres shops as well as in the tourist information offices serving this way as a basis for guided urban tours also offered by the CCVL. Based on our experience, we review and contextualise these geoscience activities and their potential for science outreach, communication and tourism. We discuss and propose a classification of different possibilities in geoscience communication and outreach based on three vertices: Science, Heritage and Geotourism. Some particularities of these visits, such as the merge between geosciences and other

Status of NEPA activities in the (Nevada Nuclear Waste Storage Investigation) program

International Nuclear Information System (INIS)

Bertram, S.G.

1981-01-01

Sandia National Laboratories, in the role of Technical Overview Contractor for the Nevada Nuclear Waste Storage Investigation (NNWSI) is, among other things, responsible for: (1) coordinating the development and integration of technical data and criteria for environmental documentation; (2) performing repository environmental analyses; and (3) preparing environmental documentation as required by the National Siting Plan and the NWTS Licensing Plan. The objective of the FY 81 studies was to prepare an Environmental Area Characterization Report (EACR) that will be the initial data base for subsequent impact analyses and to identify environmental factors and information significant for area-to-location screening. A comprehensive literature survey and evaluation was performed for each of eight topics: biology, meteorology/air quality, cultural resources, water resources, background radiation, socioeconomics, energy and mineral resources and paleontology

Assessing the proposed pre-last glacial maximum human occupation of North America at Coats-Hines-Litchy, Tennessee, and other sites

Science.gov (United States)

Tune, Jesse W.; Waters, Michael R.; Schmalle, Kayla A.; DeSantis, Larisa R. G.; Kamenov, George D.

2018-04-01

Genomic studies indicate that the first Pleistocene foragers who entered North America diverged from ancestral populations in Beringia sometime after the Last Glacial Maximum (LGM); however, several archaeological sites in North America have been proposed to predate the LGM. We present the results of our excavation and analysis of one such site, Coats-Hines-Litchy, Tennessee, which show that this site is a paleontological locality containing a geofact assemblage that pre-dates the LGM. Other sites in North America that purportedly predate the LGM occur in geomorphic contexts that are also conducive to the formation of geofact assemblages. As such, we propose that the reported artifacts from these sites were created by natural processes. No sites in North America currently provide credible evidence of a pre-LGM occupation.

Patterns and Processes of Vertebrate Evolution

Science.gov (United States)

Carroll, Robert Lynn

1997-04-01

This new text provides an integrated view of the forces that influence the patterns and rates of vertebrate evolution from the level of living populations and species to those that resulted in the origin of the major vertebrate groups. The evolutionary roles of behavior, development, continental drift, and mass extinctions are compared with the importance of variation and natural selection that were emphasized by Darwin. It is extensively illustrated, showing major transitions between fish and amphibians, dinosaurs and birds, and land mammals to whales. No book since Simpson's Major Features of Evolution has attempted such a broad study of the patterns and forces of evolutionary change. Undergraduate students taking a general or advanced course on evolution, and graduate students and professionals in evolutionary biology and paleontology will find the book of great interest.

An advanced, new long-legged bird from the Early Cretaceous of the Jehol Group (northeastern China): insights into the temporal divergence of modern birds.

Science.gov (United States)

Liu, Di; Chiappe, Luis M; Zhang, Yuguang; Bell, Alyssa; Meng, Qingjin; Ji, Qiang; Wang, Xuri

2014-11-14

We describe a new ornithuromorph bird species, Gansus zheni from the Lower Cretaceous lacustrine deposits of the Jiufotang Formation (Jehol Group), Liaoning Province, China. A cladistic analysis resolves Gansus zheni as the sister taxon of the roughly contemporaneous Gansus yumenensis (Xiagou Formation, Gansu Province), and together as the most immediate outgroup to Ornithurae. Gansus zheni is the most advanced bird known today for the Jehol Biota. Its discovery provides the best-documented case of inter-basinal correlations (Jehol and Changma basins of Liaoning and Gansu provinces, respectively) using low-taxonomic clades of fossil birds. The existence of close relatives of Ornithurae in deposits formed at about 120 million years ago helps to mitigate the long-standing controversy between molecular and paleontological evidence for the temporal divergence of modern birds (Neornithes).

Crinoid ancestry without blastozoans

Directory of Open Access Journals (Sweden)

Thomas E. Guensburg

2016-06-01

Full Text Available At present, a debate in the paleontologic literature focuses on whether or not the immediate ancestry of the Crinoidea lies in an unidentified member of the Blastozoa, which includes eocrinoids and an assemblage known variously as the “cystoids”. Those proposing to derive crinoids from within the blastozoans have recently argued for homologies in the construction of the oral region of certain derived taxa from both groups. An opposing viewpoint, outlined here, finds evidence that aside from plesiomorphies, proposed similarities are superficial and homoplastic. We suggest these superficialities represent convergent adaptive strategies. Earliest crinoids express ambulacral traits unlike any blastozoan but that are expressed in the only other pentaradial echinoderms with a known record early enough to be considered in the context of crinoid origins, edrioasteroids and edrioasteroid-like stem echinoderms.

Managing Climate Change Refugia for Climate Adaptation

Science.gov (United States)

Daly, Christopher; Dobrowski, Solomon Z.; Dulen, Deanna M.; Ebersole, Joseph L.; Jackson, Stephen T.; Lundquist, Jessica D.; Millar, Constance I.; Maher, Sean P.; Monahan, William B.; Nydick, Koren R.; Redmond, Kelly T.; Sawyer, Sarah C.; Stock, Sarah; Beissinger, Steven R.

2016-01-01

Refugia have long been studied from paleontological and biogeographical perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change refugia, here defined as areas relatively buffered from contemporary climate change over time that enable persistence of valued physical, ecological, and socio-cultural resources. We differentiate historical and contemporary views, and characterize physical and ecological processes that create and maintain climate change refugia. We then delineate how refugia can fit into existing decision support frameworks for climate adaptation and describe seven steps for managing them. Finally, we identify challenges and opportunities for operationalizing the concept of climate change refugia. Managing climate change refugia can be an important option for conservation in the face of ongoing climate change. PMID:27509088

Ancient Biomolecules from Deep Ice Cores Reveal a Forested Southern Greenland

Science.gov (United States)

Willerslev, Eske; Cappellini, Enrico; Boomsma, Wouter; Nielsen, Rasmus; Hebsgaard, Martin B.; Brand, Tina B.; Hofreiter, Michael; Bunce, Michael; Poinar, Hendrik N.; Dahl-Jensen, Dorthe; Johnsen, Sigfus; Steffensen, Jørgen Peder; Bennike, Ole; Schwenninger, Jean-Luc; Nathan, Roger; Armitage, Simon; de Hoog, Cees-Jan; Alfimov, Vasily; Christl, Marcus; Beer, Juerg; Muscheler, Raimund; Barker, Joel; Sharp, Martin; Penkman, Kirsty E.H.; Haile, James; Taberlet, Pierre; Gilbert, M. Thomas P.; Casoli, Antonella; Campani, Elisa; Collins, Matthew J.

2009-01-01

One of the major difficulties in paleontology is the acquisition of fossil data from the 10% of Earth’s terrestrial surface that is covered by thick glaciers and ice sheets. Here we reveal that DNA and amino acids from buried organisms can be recovered from the basal sections of deep ice cores and allow reconstructions of past flora and fauna. We show that high altitude southern Greenland, currently lying below more than two kilometers of ice, was once inhabited by a diverse array of conifer trees and insects that may date back more than 450 thousand years. The results provide the first direct evidence in support of a forested southern Greenland and suggest that many deep ice cores may contain genetic records of paleoenvironments in their basal sections. PMID:17615355

Managing climate change refugia for climate adaptation

Science.gov (United States)

Morelli, Toni L.; Jackson, Stephen T.

2016-01-01

Refugia have long been studied from paleontological and biogeographical perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change refugia, here defined as areas relatively buffered from contemporary climate change over time that enable persistence of valued physical, ecological, and socio-cultural resources. We differentiate historical and contemporary views, and characterize physical and ecological processes that create and maintain climate change refugia. We then delineate how refugia can fit into existing decision support frameworks for climate adaptation and describe seven steps for managing them. Finally, we identify challenges and opportunities for operationalizing the concept of climate change refugia. Managing climate change refugia can be an important option for conservation in the face of ongoing climate change.

Eric Davidson and deep time.

Science.gov (United States)

Erwin, Douglas H

2017-10-13

Eric Davidson had a deep and abiding interest in the role developmental mechanisms played in generating evolutionary patterns documented in deep time, from the origin of the euechinoids to the processes responsible for the morphological architectures of major animal clades. Although not an evolutionary biologist, Davidson's interests long preceded the current excitement over comparative evolutionary developmental biology. Here I discuss three aspects at the intersection between his research and evolutionary patterns in deep time: First, understanding the mechanisms of body plan formation, particularly those associated with the early diversification of major metazoan clades. Second, a critique of early claims about ancestral metazoans based on the discoveries of highly conserved genes across bilaterian animals. Third, Davidson's own involvement in paleontology through a collaborative study of the fossil embryos from the Ediacaran Doushantuo Formation in south China.

The idea of human prehistory: the natural sciences, the human sciences, and the problem of human origins in Victorian Britain.

Science.gov (United States)

Goodrum, Matthew R

2012-01-01

The idea of human prehistory was a provocative and profoundly influential new notion that took shape gradually during the nineteenth century. While archaeology played an important role in providing the evidence for this idea many other sciences such as geology, paleontology, ethnology, and physical anthropology all made critical contributions to discussions about human prehistory. Many works have explored the history of prehistoric archaeology but this paper examines the conceptual content of the idea of "human prehistory" as it developed in the British scientific community. Both the natural and the human sciences contributed to what was in fact a complex collection of individual elements that together constituted the prevailing idea of human prehistory, although there were other competing conceptions of human prehistory endorsed by various scientists and critics of the new view of early human history.

Correlation of proterozoic sediments of Western and Central Africa and South America based upon radiochronological and paleontological data

International Nuclear Information System (INIS)

Bonhomme, M.G.

1982-01-01

Nearly 70 new Rb-Sr isochron ages and many K-Ar conventional ages have been determined between 1975 and 1980 on Proterozoic sedimentary or metasedimentary sequences in western and Central Africa and South America. Some stratigraphic results have been established: (1) five formations have been dated of the Lower Proterozoic; (2) a long sedimentation gap occurs, mainly in western Africa and in some regions of Central Africa and South America between nearly 1600 and 1100 Ma; (3) the upper Riphean assemblages of stromatolites have been dated and compared to those of the Eurasian craton; (4) two main glacial events have been dated, the first one placed at ca. 950 Ma, the second during the Vendian, at ca. 650-620 Ma; (5) it can be stated that, when applied to Precambrian sequences, all stratigraphic methods must be used together. (Auth.)

Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology

Science.gov (United States)

Dorsey, Rebecca J.; O’Connell, Brennan; McDougall-Reid, Kristin; Homan, Mindy B.

2018-01-01

The Colorado River in the southwestern U.S. provides an excellent natural laboratory for studying the origins of a continent-scale river system, because deposits that formed prior to and during river initiation are well exposed in the lower river valley and nearby basinal sink. This paper presents a synthesis of regional stratigraphy, sedimentology, and micropaleontology from the southern Bouse Formation and similar-age deposits in the western Salton Trough, which we use to interpret processes that controlled the birth and early evolution of the Colorado River. The southern Bouse Formation is divided into three laterally persistent members: basal carbonate, siliciclastic, and upper bioclastic members. Basal carbonate accumulated in a tide-dominated marine embayment during a rise of relative sea level between ~ 6.3 and 5.4 Ma, prior to arrival of the Colorado River. The transition to green claystone records initial rapid influx of river water and its distal clay wash load into the subtidal marine embayment at ~ 5.4–5.3 Ma. This was followed by rapid southward progradation of the Colorado River delta, establishment of the earliest through-flowing river, and deposition of river-derived turbidites in the western Salton Trough (Wind Caves paleocanyon) between ~ 5.3 and 5.1 Ma. Early delta progradation was followed by regional shut-down of river sand output between ~ 5.1 and 4.8 Ma that resulted in deposition of marine clay in the Salton Trough, retreat of the delta, and re-flooding of the lower river valley by shallow marine water that deposited the Bouse upper bioclastic member. Resumption of sediment discharge at ~ 4.8 Ma drove massive progradation of fluvial-deltaic deposits back down the river valley into the northern Gulf and Salton Trough.These results provide evidence for a discontinuous, start-stop-start history of sand output during initiation of the Colorado River that is not predicted by existing models for this system. The underlying controls on punctuated sediment discharge are assessed by comparing the depositional chronology to the record of global sea-level change. The lower Colorado River Valley and Salton Trough experienced marine transgression during a gradual fall in global sea level between ~ 6.3 and 5.5 Ma, implicating tectonic subsidence as the main driver of latest Miocene relative sea-level rise. A major fall of global sea level at 5.3 Ma outpaced subsidence and drove regional delta progradation, earliest flushing of Colorado River sand into the northern Gulf of California, and erosion of Bouse basal carbonate and siliciclastic members. The lower Colorado River valley was re-flooded by shallow marine waters during smaller changes in global sea level ~ 5.1–4.8 Ma, after the river first ran through it, which requires a mechanism to stop delivery of sand to the lower river valley. We propose that tectonically controlled subsidence along the lower Colorado River, upstream of the southern Bouse study area, temporarily trapped sediment and stopped delivery of sand to the lower river valley and northern Gulf of California for ~ 200–300 kyr. Massive progradation of the fluvial-deltaic system back down the river valley into the Salton Trough starting ~ 4.8–4.5 Ma apparently was driven by a huge increase in sediment discharge that overwhelmed the sediment-storage capacity of sub-basins along the lower river corridor and established the fully integrated river channel network.

Statistical shape analysis using 3D Poisson equation--A quantitatively validated approach.

Science.gov (United States)

Gao, Yi; Bouix, Sylvain

2016-05-01

Statistical shape analysis has been an important area of research with applications in biology, anatomy, neuroscience, agriculture, paleontology, etc. Unfortunately, the proposed methods are rarely quantitatively evaluated, and as shown in recent studies, when they are evaluated, significant discrepancies exist in their outputs. In this work, we concentrate on the problem of finding the consistent location of deformation between two population of shapes. We propose a new shape analysis algorithm along with a framework to perform a quantitative evaluation of its performance. Specifically, the algorithm constructs a Signed Poisson Map (SPoM) by solving two Poisson equations on the volumetric shapes of arbitrary topology, and statistical analysis is then carried out on the SPoMs. The method is quantitatively evaluated on synthetic shapes and applied on real shape data sets in brain structures. Copyright © 2016 Elsevier B.V. All rights reserved.

The Upper Eocene oncolitic bioherms of Rybalsky quarry (Dnepropetrovsk as indicator facies Mandrikovka beds

Directory of Open Access Journals (Sweden)

Stefanskyy V.L.

2014-12-01

Full Text Available This is the first description of oncolites and theirs bioherms from Mandrikovka layers (Rybalskiy quarry, Dnepropetrovsk. In the Mandrykovka layers of Rybalsky career Dnepropetrovsk there are numerous remains of cyanobacterial paleocoenosis (oncolites fossil covers bacteria, fossilized microbial mat. Nodule oncolites here are rock-forming and greatly affect the lithological composition Mandrykovka rocks, sometimes exceeding half he total and forming bioherms. But as currently paleobaktery taxonomy is still under development, the presence of residues nannoorganizmes in the Mandrykovka layers (fossils and fossilized bacteria covers cyanobacterial mats does not allow us to draw any stratigraphic conclusions. The Mandrykovka layers formed in the littoral environment, characterized by a unique set of paleontological and locally common in the southern part of the Dnipropetrovsk city. At present the Mandrykovka layers are not adequately investigated and require complex additional exploration.

A preliminary study of paleotsunami deposit along the south coast of East Java: Pacitan-Banyuwangi

International Nuclear Information System (INIS)

Anugrah, Suci D.; Istiyanati; Zaim, Yahdi; Rizal, Yan; Aswan

2015-01-01

Along the southern coast of East Java Indonesia, at a number of localities, it can be identified and attempted to assign the age of tsunami deposit. Laboratory analyses were conducted also to support this study such as Granulometry, Paleontology and radiometric dating analysis. The presence of tsunami 1994 deposit in the area of Pancer, Lampon, Prigi and Grajagan was found, as a result of 7.8 Magnitude Banyuwangi Earthquake. The radiometric dating analysis also identified some paleotsunami deposit of about 1921 and 1930 in the area of Prigi and Teleng. This paleotsunami is assumed to have a correlation with an earthquake in the south of Java at the same time. An outcrop in the Prigi and Teleng strongly convinced the fact of an earthquake generated tsunami in the south of Java in the year of about 1921 and 1930

Regional magnetic anomaly constraints on continental rifting

Science.gov (United States)

Vonfrese, R. R. B.; Hinze, W. J.; Olivier, R.; Bentley, C. R.

1985-01-01

Radially polarized MAGSAT anomalies of North and South America, Europe, Africa, India, Australia and Antarctica demonstrate remarkably detailed correlation of regional magnetic lithospheric sources across rifted margins when plotted on a reconstruction of Pangea. These major magnetic features apparently preserve their integrity until a superimposed metamorphoric event alters the magnitude and pattern of the anomalies. The longevity of continental scale magnetic anomalies contrasts markedly with that of regional gravity anomalies which tend to reflect predominantly isostatic adjustments associated with neo-tectonism. First observed as a result of NASA's magnetic satellite programs, these anomalies provide new and fundamental constraints on the geologic evolution and dynamics of the continents and oceans. Accordingly, satellite magnetic observations provide a further tool for investigating continental drift to compliment other lines of evidence in paleoclimatology, paleontology, paleomagnetism, and studies of the radiometric ages and geometric fit of the continents.

The role of SANRAD facility in quantitative and morphological investigation

International Nuclear Information System (INIS)

Nshimirimana, Robert; Beer, Frikkie de; Radebe, Mabuti

2011-01-01

The SANRAD (South African Neutron Radiography) facility hosts a neutron/X-ray tomography system, which is extensively being utilized in non-destructive examination experiments where it is necessary to determine the properties (e.g. size, porosity, permeability and morphology) of samples. Those properties have a great importance in a variety of fields such as nuclear shielding, paleontology, geosciences, anatomy and reverse engineering studies. Quantitative and morphological investigations require a tomography system capable of producing tomograms with a high spatial resolution and free of artefacts where specialized imaging software is applied in the investigations. The SANRAD facility is used by the scientific and engineering communities in their qualitative, quantitative and morphological investigations. The capability of the SANRAD facility to investigate qualitatively and quantitatively the internal structure of several objects non-destructively is demonstrated with special emphasis on the precision and accuracy of the system.

Earliest Pleistocene hominid cranial remains from Dmanisi, Republic of Georgia: taxonomy, geological setting, and age.

Science.gov (United States)

Gabunia, L; Vekua, A; Lordkipanidze, D; Swisher, C C; Ferring, R; Justus, A; Nioradze, M; Tvalchrelidze, M; Antón, S C; Bosinski, G; Jöris, O; Lumley, M A; Majsuradze, G; Mouskhelishvili, A

2000-05-12

Archaeological excavations at the site of Dmanisi in the Republic of Georgia have uncovered two partial early Pleistocene hominid crania. The new fossils consist of a relatively complete cranium and a second relatively complete calvaria from the same site and stratigraphic unit that yielded a hominid mandible in 1991. In contrast with the uncertain taxonomic affinity of the mandible, the new fossils are comparable in size and morphology with Homo ergaster from Koobi Fora, Kenya. Paleontological, archaeological, geochronological, and paleomagnetic data from Dmanisi all indicate an earliest Pleistocene age of about 1.7 million years ago, supporting correlation of the new specimens with the Koobi Fora fossils. The Dmanisi fossils, in contrast with Pleistocene hominids from Western Europe and Eastern Asia, show clear African affinity and may represent the species that first migrated out of Africa.

History and development of ABCDEFG: a data standard for geosciences

Directory of Open Access Journals (Sweden)

M. Petersen

2018-01-01

Full Text Available Museums and their collections have specially customized databases in order to optimally gather and record their contents and associated metadata associated with their specimens. To share, exchange, and publish data, an appropriate data standard is essential. ABCD (Access to Biological Collection Data is a standard for biological collection units, including living and preserved specimen, together with field observation data. Its extension, EFG (Extension for Geoscience, enables sharing and publishing data related to paleontological, mineralogical, and petrological objects. The standard is very granular and allows detailed descriptions, including information about the collection event itself, the holding institution, stratigraphy, chemical analysis, and host rock. The standard extension was developed in 2006 and has been used since then by different initiatives and applied for the publication of collection-related data in domain-specific and interdisciplinary portals.

Topology with applications topological spaces via near and far

CERN Document Server

Naimpally, Somashekhar A

2013-01-01

The principal aim of this book is to introduce topology and its many applications viewed within a framework that includes a consideration of compactness, completeness, continuity, filters, function spaces, grills, clusters and bunches, hyperspace topologies, initial and final structures, metric spaces, metrization, nets, proximal continuity, proximity spaces, separation axioms, and uniform spaces. This book provides a complete framework for the study of topology with a variety of applications in science and engineering that include camouflage filters, classification, digital image processing, forgery detection, Hausdorff raster spaces, image analysis, microscopy, paleontology, pattern recognition, population dynamics, stem cell biology, topological psychology, and visual merchandising. It is the first complete presentation on topology with applications considered in the context of proximity spaces, and the nearness and remoteness of sets of objects. A novel feature throughout this book is the use of near and...

Quantitative Analysis of Neogene Foraminfera in the Central Niger Delta

International Nuclear Information System (INIS)

Ojo, A. O.; Salami, M. B.

2003-01-01

A ranking and Scaling (RASC) computer programme for zonation and normality testing of paleontological events was employed to identify assemblages of foraminifera species in the sections studied. The emphasis is on ease of zonal recognition and reliability in correlation. A four fold interval zonation of benthonic and some planktonic foraminifera were established. Two distinct temporal and four depositional environments are recognizable. A few benthonic foraminifera appear to have biostratigraphic significance. Bulumina elegans is present in the early Miocene. Cyclammina cancellata, in the middle-late Miocene, while Brizalina beyrichi and Bolivina variabilis are restricted to late Miocene in the studied samples. However, these distributions may be environmentally controlled and therefore may be tell zones. The presence and abundance of neritic fauna with lignitic materials indicate alternating shallow marine and non-marine conditions during deposition in parts of the Niger-delta

Abstracts of the GAC-MAC annual meeting : planet Earth

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

A broad range of issues dealing with geosciences were discussed at this joint meeting of the Geological Association of Canada and the Mineralogical Association of Canada, with particular emphasis on resource exploration. Other topics of discussion included economic geology; structural geology and tectonics; mineralogy, crystallography and mineral chemistry; igneous petrology, volcanology and metamorphic petrology; and, sedimentology, paleontology and micropaleontology. The challenges facing the Canadian geoscience community regarding greenhouse gases and global change were outlined along with new tools and technologies for mineral exploration. Over a thousand specialists in Earth sciences from Canada, the United States and Europe participated in the general session as well as conference exhibits, symposia, special courses, workshops, poster sessions, field trips and an outreach program. The conference featured more than 150 presentations, of which 8 have been catalogued separately for inclusion in this database.

A preliminary study of paleotsunami deposit along the south coast of East Java: Pacitan-Banyuwangi

Energy Technology Data Exchange (ETDEWEB)

Anugrah, Suci D.; Istiyanati [Tsunami Mitigation Division - Meteorogical Climatologycal and Geophysical Agency, Jakarta (Indonesia); Zaim, Yahdi; Rizal, Yan; Aswan [Geology Department, Faculty of Earth Sciences and Technology - Bandung Institute of Technolog, Bandung (Indonesia)

2015-04-24

Along the southern coast of East Java Indonesia, at a number of localities, it can be identified and attempted to assign the age of tsunami deposit. Laboratory analyses were conducted also to support this study such as Granulometry, Paleontology and radiometric dating analysis. The presence of tsunami 1994 deposit in the area of Pancer, Lampon, Prigi and Grajagan was found, as a result of 7.8 Magnitude Banyuwangi Earthquake. The radiometric dating analysis also identified some paleotsunami deposit of about 1921 and 1930 in the area of Prigi and Teleng. This paleotsunami is assumed to have a correlation with an earthquake in the south of Java at the same time. An outcrop in the Prigi and Teleng strongly convinced the fact of an earthquake generated tsunami in the south of Java in the year of about 1921 and 1930.

La Ruta de los Origenes stops in Montsec: observations and other educational activities

Science.gov (United States)

Ribas, S. J.

2013-05-01

La Ruta de los Origenes is an European Cooperation Project POCTEFA funded by FEDER- UE. The main objective of this project is to establish a touristic route on both sides of the Pyrenees to approach Origins topic to the public. This project is developed by six partners, three in Catalonia and three in Midi-Pyrenees, and is focused in Astronomy, Paleontology and Archaelogy. Montsec mountains are placed in the Pre-Pyrenees area of Lleida province and they are a very good place for astronomy (dark skies, good seeing, good weather conditions). Parc Astronomic Montsec is the major astronomy project in that area and it includes a research astronomical observatory and an outreach and education center. So Montsec mountains and their Parc Astronomic are one of the stops of this route with an important number of activities to approach astronomy to public.

Oxygen - A Four Billion Year History

DEFF Research Database (Denmark)

Canfield, Donald Eugene

The air we breathe is twenty-one percent oxygen, an amount higher than on any other known world. While we may take our air for granted, Earth was not always an oxygenated planet. How did it become this way? Oxygen is the most current account of the history of atmospheric oxygen on Earth. Donald...... Canfield--one of the world's leading authorities on geochemistry, earth history, and the early oceans--covers this vast history, emphasizing its relationship to the evolution of life and the evolving chemistry of the Earth. With an accessible and colorful first-person narrative, he draws from a variety...... of fields, including geology, paleontology, geochemistry, biochemistry, animal physiology, and microbiology, to explain why our oxygenated Earth became the ideal place for life. Describing which processes, both biological and geological, act to control oxygen levels in the atmosphere, Canfield traces...

Optical dating of the anastasia formation, northeastern florida, USA

Science.gov (United States)

Burdette, K.E.; Rink, J.W.; Means, G.H.; Portell, R.W.

2009-01-01

The single-aliquot regenerative-dose (SAR) procedure was used to obtain optically stimulated luminescence ages to determine the depositional age of the upper part of the Anastasia Formation. This unit, which crops out along the east coast of Florida, is one of the most culturally and economically important coquina deposits in North America. Rock samples from the upper three meters of exposure at three locations were collected. Additional materials for paleontological analysis were also taken. Based on our samples, the luminescence ages of the Anastasia Formation are well within marine isotope stage 5, which is supported by the results of Osmond et al. (1970) based on U/Th ages. The associated fossil assemblages support our luminescence age determinations. Associated fossils fall within the Rancholabrean North American Land Mammal Age (300 10 ka) and the fossil mollusk assemblage consists entirely of modern species.

Isotope techniques in studies of paleontology environmental reconstruction (vegetation and climate) in the delayed quaternario of two Brazilian regions

International Nuclear Information System (INIS)

Gouveia, Susy E.M.; Pessenda, Luiz C.R.; Freitas, Hermes A.; Silva, Vanessa F.; Pellegrinotti, Thais C.; Aravena, Ramon; Scheel-Ybert, Rita; Bendassolli, Jose A.

2000-01-01

This paper presents an attempt to reconstruct vegetation and climate changes in the central region of the state of Sao Paulo (Jaguariuna) and west of the state of Mato Grosso (Pontes e Lacerda) during the last 12,000 years BP, based on δ 13 C values of soil organic matter (SOM), 14 C dating and botanical identification of buried charcoal in the soil profiles. Sampling site in Sao Paulo was located under natural vegetation ('cerradao'), along the slope of small hills and in the top of slope under the semi-deciduous forest in Mato Grosso. Charcoal was found predominantly between 150 and 50 cm depth, indicating a period of greater frequency of fires in these regions, between 6,000 and 3,000 years BP. More enriched values of δ 13 C of SOM (predominance of C 4 plants) were observed from approximately 12,000 to 7,000 years BP in Jaguariuna, indicating drier climate when compared with nowadays conditions. The charcoal analyses indicated the predominance of cerrado species. In Pontes e Lacerda site, the δ 13 C profile suggests the presence of C 3 vegetation (forest) during the last 10,000 years and the most of identified charcoal fragments indicated the presence of semi-deciduous forest as well as cerrado species. (author)

Las áreas de mitosis forjan nuevos estilos en los estudios sobre paleontología de mamíferos

Directory of Open Access Journals (Sweden)

Ruiz Bustos, A.

2006-12-01

Full Text Available Descriptive and comparative morphology supports mammal phylogeny. Since the 19th century, molars have been compared in order to pinpoint the characteristics which best define lineages. This information is assembled in the classic theories (Cope, 1883; Osborn, 1907. The lack of any explicit assessment on the genetic and embryonic development of the phenotypic criteria makes subjective its taxonomic valuation, creating conflictive hypotheses, and the taxonomy must be constantly revised. The solution comes with establishing the genesis of each molar cusp as a result of the morphogenesis of a specific area in the dental papilla, with high cellular density and intense mitotic activity. This allows us to establish an ontogenetic development which relates each adult characteristic with its corresponding embryonic morphology, where is possible to link the biotechnological data. A reference sequence (SR is the arrangement of the molar’s assessed characteristics forming an unalterable series and which can be correlated with genotype sequences. Phylogenies are described using reference sequences, with their similarity weighted and located in time and habitat. This specific ontogeny creates a new conceptual base in classic morphology, which is able to correlate the phenotype with DNA sequences, including the use of ancient DNA techniques.Desde el siglo XIX, la morfología descriptiva y comparada de los molares, basada en la observación directa y comparación morfológica, es utilizada para elegir los caracteres, que mejor fundamenta la filogenia de los linajes de mamíferos. Los datos obtenidos muestran una conceptuación mediante las teorías clásicas (Cope, 1883; Osborn, 1907. La falta de valoración explícita de la naturaleza biológica de los caracteres elegidos como filogenéticamente significativos en las teorías clásicas, es causa de analogías falsas, que crean paradojas en los linajes y obligan a revisar constantemente la taxonomía. A partir de las observaciones que constatan la génesis de cada tubérculo, como resultado de la morfogénesis de un área específica en la papila dental con elevada densidad celular e intensa actividad mitótica, que es petrificada por una capa de esmalte, es enunciado un desarrollo ontogenético donde cada carácter adulto está relacionado con su correspondiente morfología embrionaria. Esta ontogenia donde están integrados: morfología adulta, información genética, bioquímica y procesos de adaptación ecológica, crea un ámbito conceptual de morfología descriptiva que valora la naturaleza biológica de cada carácter por: capacidad para ser heredado y grado de participación en la función masticadora. Los caracteres de un molar con su naturaleza biológica valorada, dispuestos en una serie inalterable, forman la serie de referencia (SR. Las series de referencia cuando es ponderada su similitud y ubicadas en tiempo y hábitats, describen filogenias. La ontogenia basada en la naturaleza biológica de los caracteres crea una nueva base conceptual en la morfología clásica, que es capaz de correlacionar el fenotipo con secuencias de ADN, incluyendo el empleo de técnicas para recuperar el ADN en los fósiles.

Harry S. Truman Dam and REservoir, Missouri, Mitigation of the Adverse Effects upon the Local Paleontological Resources. Volume 1.

Science.gov (United States)

1983-01-01

scripta elegans , occuring from Ohio and Iowa to New Mexico, prefers quiet water with muddy bottoms and much vegetation. Today Chrysemys scripta ...Chrysemys ( Trachemys ) scripta Pond slider ABUNDANCE. One individual. A single specimen, the medial portion of the first left pleural bone, ISM 490,014 (Moodie...75,000 years ago. *" Systematic Discussion of Trolinger Spring I Fauna Class REPTILIA Order CHELONIA Family TESTUDINIDAE Chrysemys ( Trachemys

Enhancing observation by drawing: Alveolinids models by Manfred Reichel (1896-1984)

Science.gov (United States)

Leria, Maria

2017-04-01

Graphic representation is a fundamental tool in morphological studies, as paleontology. A paradigmatic example is the alveolinid drawings of Prof. Manfred Reichel (1896-1984). Thanks to these drawings his research on foraminifera, had an important impact on micropaleontology. Manfred Reichel studied Fine Arts, but later he began a scientific career on biological sciences and becoming a professor in micropaleontology, at the Geological and Paleontological Institute of the University of Basel, Switzerland. His background in art had a benefit in his scientific production, especially with the extremely complex foraminiferal structures. By means of illustrations, inspired by the French naturalists, he was able to solve the most complex internal architecture of forams. His drawings display foraminifera's internal 3D structure in such a comprehensible way that has not been improved using modern techniques. His work has been used by different generations of paleontologist to understand the internal architecture of forams and are still used today. The aim of this study is to analyze the process that Reichel followed to create some of his most representative drawings. This study is based on the examination of a selection of Reichel's drawings (n>40) held at the Natural History Museum in Basel. In addition, his family and students have been interviewed supplying useful information to understand how he applied his artistic skills to teach and research. This study illustrates the steps followed by Reichel in the creation of a drawing of alveolinid. The process represents the transformation of the morphological data from 2D images (polished rock sections) into a comprehensible 3D image. A description of the process of observation, comparison, sketches and studies, concluding with the final three-dimensional drawing is shown. The results show that that the classical convention in drawing is still and irreplaceable tool in natural sciences, because it allows to define aspects that

Natural selection drives the evolution of ant life cycles.

Science.gov (United States)

Wilson, Edward O; Nowak, Martin A

2014-09-02

The genetic origin of advanced social organization has long been one of the outstanding problems of evolutionary biology. Here we present an analysis of the major steps in ant evolution, based for the first time, to our knowledge, on combined recent advances in paleontology, phylogeny, and the study of contemporary life histories. We provide evidence of the causal forces of natural selection shaping several key phenomena: (i) the relative lateness and rarity in geological time of the emergence of eusociality in ants and other animal phylads; (ii) the prevalence of monogamy at the time of evolutionary origin; and (iii) the female-biased sex allocation observed in many ant species. We argue that a clear understanding of the evolution of social insects can emerge if, in addition to relatedness-based arguments, we take into account key factors of natural history and study how natural selection acts on alleles that modify social behavior.

Three dimensional reconstruction of fossils with X-ray CT and computer graphics

Energy Technology Data Exchange (ETDEWEB)

Hamada, Takashi; Tateno, Satoko (Tokyo Univ. (Japan). Coll. of Arts and Sciences); Suzuki, Naoki

1991-12-01

We have developed a method for three dimensional (3D) visualization of fossils such as trilobites and ammonites by non-destructive measurement and computer graphics. The imaging techniques in the medical sciences are applied for fossils by us to have quantitative data analyses on the structural and functional features of some extinct creatures. These methods are composed of a high resolutional X-ray computed tomography (X-ray CT) and computer graphics. We are able to observe not only outer shape but also inner structure of fossils as a 3D image by this method. Consequently, the shape and volume are measurable on these 3D image quantitatively. In addition to that, it is able to reconstruct an ideal figure from the deformed fossils by graphical treatments of the data. Such a 3D reconstruction method is useful to obtain a new information from the paleontological standpoint. (author).

The currency and tempo of extinction.

Science.gov (United States)

Regan, H M; Lupia, R; Drinnan, A N; Burgman, M A

2001-01-01

This study examines estimates of extinction rates for the current purported biotic crisis and from the fossil record. Studies that compare current and geological extinctions sometimes use metrics that confound different sources of error and reflect different features of extinction processes. The per taxon extinction rate is a standard measure in paleontology that avoids some of the pitfalls of alternative approaches. Extinction rates reported in the conservation literature are rarely accompanied by measures of uncertainty, despite many elements of the calculations being subject to considerable error. We quantify some of the most important sources of uncertainty and carry them through the arithmetic of extinction rate calculations using fuzzy numbers. The results emphasize that estimates of current and future rates rely heavily on assumptions about the tempo of extinction and on extrapolations among taxa. Available data are unlikely to be useful in measuring magnitudes or trends in current extinction rates.

Structure and dating errors in the geologic time scale and periodicity in mass extinctions

Science.gov (United States)

Stothers, Richard B.

1989-01-01

Structure in the geologic time scale reflects a partly paleontological origin. As a result, ages of Cenozoic and Mesozoic stage boundaries exhibit a weak 28-Myr periodicity that is similar to the strong 26-Myr periodicity detected in mass extinctions of marine life by Raup and Sepkoski. Radiometric dating errors in the geologic time scale, to which the mass extinctions are stratigraphically tied, do not necessarily lessen the likelihood of a significant periodicity in mass extinctions, but do spread the acceptable values of the period over the range 25-27 Myr for the Harland et al. time scale or 25-30 Myr for the DNAG time scale. If the Odin time scale is adopted, acceptable periods fall between 24 and 33 Myr, but are not robust against dating errors. Some indirect evidence from independently-dated flood-basalt volcanic horizons tends to favor the Odin time scale.

Evolution of viviparous reproduction in Paleozoic and Mesozoic reptiles.

Science.gov (United States)

Blackburn, Daniel G; Sidor, Christian A

2014-01-01

Although viviparity (live-bearing reproduction) is widely distributed among lizards and snakes, it is entirely absent from other extant Reptilia and many extinct forms. However, paleontological evidence reveals that viviparity was present in at least nine nominal groups of pre-Cenozoic reptiles, representing a minimum of six separate evolutionary origins of this reproductive mode. Two viviparous clades (sauropterygians and ichthyopterygians) lasted more than 155 million years, a figure that rivals the duration of mammalian viviparity. Circumstantial evidence indicates that extinct viviparous reptiles had internal fertilization, amniotic fetal membranes, and placentas that sustained developing embryos via provision of respiratory gases, water, calcium, and possibly organic nutrients. Production of offspring via viviparity facilitated the invasion of marine habitats in at least five reptilian lineages. Thus, this pattern of embryonic development and reproduction was central to the ecology and evolution of these ancient animals, much as it is to numerous extant species of vertebrates.

Lithofacies and sequence stratigraphic description of the upper part of the Avon Park Formation and the Arcadia Formation in U.S. Geological Survey G–2984 test corehole, Broward County, Florida

Science.gov (United States)

Cunningham, Kevin J.; Robinson, Edward

2017-07-18

Rock core and sediment from U.S. Geological Survey test corehole G–2984 completed in 2011 in Broward County, Florida, provide an opportunity to improve the understanding of the lithostratigraphic, sequence stratigraphic, and hydrogeologic framework of the intermediate confining unit and Floridan aquifer system in southeastern Florida. A multidisciplinary approach including characterization of sequence stratigraphy, lithofacies, ichnology, foraminiferal paleontology, depositional environments, porosity, and permeability was used to describe the geologic samples from this test corehole. This information has produced a detailed characterization of the lithofacies and sequence stratigraphy of the upper part of the middle Eocene Avon Park Formation and Oligocene to middle Miocene Arcadia Formation. This enhancement of the knowledge of the sequence stratigraphic framework is especially important, because subaerial karst unconformities at the upper boundary of depositional cycles at various hierarchical scales are commonly associated with secondary porosity and enhanced permeability in the Floridan aquifer system.

Oscilaciones del clima postglacial del Noroeste de España registradas en los sedimentos de la Ría de Vigo

Directory of Open Access Journals (Sweden)

Ramón MARGALEF LÓPEZ

2009-11-01

Full Text Available Existe una relación estrecha entre las características de un medio ambiente y los organismos que en él se desarrollan; estos organismos pueden emplearse, por tanto, como indicadores de aquellas propiedades —temperatura, salinidad, etc.—, cuando nos es imposible su apreciación directa, que es lo que ocurre en relación con épocas pasadas. El estudio de restos de organismos indicadores, contenidos en materiales depositados de manera continuada, permite deducir la sucesión de los climas. Así procede la paleontología en general y, en una escala más fina, la palinología, es decir, la investigación del polen y otros vestigios intercalados en el espesor de las turberas, a la que se deben los ciatos más consistentes sobre climatología del cuaternario.

Formation of the Isthmus of Panama

Science.gov (United States)

O'Dea, Aaron; Aguilera, Orangel; Aubry, Marie-Pierre; Berggren, William A.; Cione, Alberto L.; Coates, Anthony G.; Collins, Laurel S.; Coppard, Simon E.; Cozzuol, Mario A.; de Queiroz, Alan; Duque-Caro, Herman; Eytan, Ron I.; Farris, David W.; Gasparini, German M.; Grosmman, Ethan L.; Jackson, Jeremy B. C.; Johnson, Kenneth G.; Keigwin, Lloyd D.; Knowlton, Nancy; Leigh, Egbert G.; Leonard-Pingel, Jill S.; Lessios, Hailaos A.; Marko, Peter B.; Norris, Richard D.; Rachello-Dolmen, Paola G.; Restrepo-Moreno, Sergio A.; Soibelzon, Leopoldo; Stallard, Robert F.; Todd, Jonathan A.; Vermeiju, Geerat J.; Woodburne, Michael O.

2016-01-01

The formation of the Isthmus of Panama stands as one of the greatest natural events of the Cenozoic, driving profound biotic transformations on land and in the oceans. Some recent studies suggest that the Isthmus formed many millions of years earlier than the widely recognized age of approximately 3 million years ago (Ma), a result that if true would revolutionize our understanding of environmental, ecological, and evolutionary change across the Americas. To bring clarity to the question of when the Isthmus of Panama formed, we provide an exhaustive review and reanalysis of geological, paleontological, and molecular records. These independent lines of evidence converge upon a cohesive narrative of gradually emerging land and constricting seaways, with formation of the Isthmus of Panama sensu stricto around 2.8 Ma. The evidence used to support an older isthmus is inconclusive, and we caution against the uncritical acceptance of an isthmus before the Pliocene.

Live phylogeny with polytomies: Finding the most compact parsimonious trees.

Science.gov (United States)

Papamichail, D; Huang, A; Kennedy, E; Ott, J-L; Miller, A; Papamichail, G

2017-08-01

Construction of phylogenetic trees has traditionally focused on binary trees where all species appear on leaves, a problem for which numerous efficient solutions have been developed. Certain application domains though, such as viral evolution and transmission, paleontology, linguistics, and phylogenetic stemmatics, often require phylogeny inference that involves placing input species on ancestral tree nodes (live phylogeny), and polytomies. These requirements, despite their prevalence, lead to computationally harder algorithmic solutions and have been sparsely examined in the literature to date. In this article we prove some unique properties of most parsimonious live phylogenetic trees with polytomies, and their mapping to traditional binary phylogenetic trees. We show that our problem reduces to finding the most compact parsimonious tree for n species, and describe a novel efficient algorithm to find such trees without resorting to exhaustive enumeration of all possible tree topologies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Theropoda dinosaurs tracks from Triassic basin nd Ischigualasto - Villa Union, western Argentina; Huellas de dinosaurios teropodos de la cuencas triasica de Ischigualasto-Villa Union, oeste de Argentina

Energy Technology Data Exchange (ETDEWEB)

Contreras, V; Bracco, A [Instituto de Geologia Emiliano P. Aparicio, Facultad de Ciencias Exactas Fisicas y Naturales, Universidad Nacional de San Juan (Argentina)

2004-09-01

The Anchisauripus isp. and Theropoda indet. dinosaurs tracks from the Triassic Los Rastros and Ischigualasto formations, at the Ischigualasto-Villa Union Basin, Western Argentina, are described in this paper. This record completes the paleontological data provided by rest of bones and increases the stratigraphic range of some taxa in which bones are either missing or scarse. On the other hand, this report also allows us to enlarge the faunistic assemblage of some vertebrate assemblages. [Spanish] Se describen huellas de dinosaurios teropodos asignados a Anchisauripus isp. y Theropoda indet. para las formaciones triasicas de Los Rastros e Ischigualasto en el Oeste de Argentina. Los sitios con huellas en la cuenca triasica de Ischigualasto - Villa Union complementan los datos paleontologicos ofrecidos por los restos oseos, ampliando el rango estratigrafico de algunos taxa donde sus huesos estan ausentes o son relativamente escasos e incluso permiten ampliar el cortejo faunistico de algunas asociaciones de vertebrados.

Development of a system for determination of the 13C/12C isotopic ratio with high spatial resolution

International Nuclear Information System (INIS)

Kristiansson, Per.; Hode, Tomas; Auzelyte, Vaida; Elfman, Mikael; Malmqvist, Klas; Nilsson, Christer; Pallon, Jan; Shariff, Asad; Wegden, Marie

2004-01-01

Stable carbon isotopes play an important role in the interpretation of biological activity, particularly when the fossil record is studied. In combination with morphological and chemical data, isotopic information can be useful in paleontology and astrobiology. In this paper the development of a microanalytical ion beam system for the measurement of the carbon isotope ratio with high spatial resolution and good statistics is presented. The technique used is elastic scattering of alpha particles with an energy of 2.75 MeV. At this energy the 13 C cross-section is enhanced relative to the Rutherford cross-section and while the 12 C cross-section is reduced. The optimisation of the system is described, including sample preparation and the design of the particle detection system for high efficiency combined with good energy resolution. Finally, some results from the initial test run of the system are shown and discussed

Three dimensional reconstruction of fossils with X-ray CT and computer graphics

International Nuclear Information System (INIS)

Hamada, Takashi; Tateno, Satoko; Suzuki, Naoki.

1991-01-01

We have developed a method for three dimensional (3D) visualization of fossils such as trilobites and ammonites by non-destructive measurement and computer graphics. The imaging techniques in the medical sciences are applied for fossils by us to have quantitative data analyses on the structural and functional features of some extinct creatures. These methods are composed of a high resolutional X-ray computed tomography (X-ray CT) and computer graphics. We are able to observe not only outer shape but also inner structure of fossils as a 3D image by this method. Consequently, the shape and volume are measurable on these 3D image quantitatively. In addition to that, it is able to reconstruct an ideal figure from the deformed fossils by graphical treatments of the data. Such a 3D reconstruction method is useful to obtain a new information from the paleontological standpoint. (author)

MODEL RECONSTRUCTION OF THE VEGETATION COVER OF THE SOUTH OF THE WEST SIBERIAN PLAIN FROM THE LATE PALEOLITHIC PERIOD UNTIL THE LATE XIX CENTURY

Directory of Open Access Journals (Sweden)

М. А. Kharitonenkov

2016-06-01

Full Text Available Model reconstruction of vegetation cover of the south of the West Siberian Plain from the late Pleistocene to the modern era has been carried out on the basis of the associated chronological analysis of paleontological, archaeological and paleoclimate data. We have determined the starting point of active vegetation transformation in the south of the West Siberian Plain as a result of tradition-bound exploitation of natural resources. Periods of maximum anthropogenic load – peak and relative recession – on vegetation cover, acting as a further determinant factor, have been determined in this study for the first time. Comprehensive analysis and new understanding of palynological, paleozoological, archaeological and paleoclimate data in terms of theoretical synecology confirmed the notions on the determinant role of the anthropogenic factor in the transformation of the Pleistocene forest-meadow-steppe vegetation into contemporary communities of the southern taiga, the subtaiga and the forest-steppe of the West Siberian Plain.

The Sima de los Huesos hominids date to beyond U/Th equilibrium (>350 kyr) and perhaps to 400-500 kyr: New radiometric dates

Science.gov (United States)

Bischoff, J.L.; Shamp, D.D.; Aramburu, Arantza; Arsuaga, J.L.; Carbonell, E.; Bermudez de Castro, Jose Maria

2003-01-01

The Sima de los Huesos site of the Atapuerca complex near Burgos, Spain contains the skeletal remains of at least 28 individuals in a mud breccia underlying an accumulation of the Middle Pleistocene cave bear (U. deningeri). Earlier dating estimates of 200 to 320 kyr were based on U-series and ESR methods applied to bones, made inaccurate by unquantifiable uranium cycling. We report here on a new discovery within the Sima de los Huesos of human bones stratigraphically underlying an in situ speleothem. U-series analyses of the speleothem shows the lower part to be at isotopic U/Th equilibrium, translating to a firm lower limit of 350 kyr for the SH hominids. Finite dates on the upper part suggest a speleothem growth rate of c. 1 cm/32 kyr. This rate, along with paleontological constraints, place the likely age of the hominids in the interval of 400 to 600 kyr. ?? 2002 Elsevier Science Ltd. All rights reserved.

Steppic environments at the end of the upper pleistocene in southern Tunisia (Oued el Akarit)

Science.gov (United States)

Brun, Annik; Guerin, Claude; Levy, Alain; Riser, Jean; Rognon, Pierre

The cross section of the Oued el Akarit, 25 km North of Gabès, is of considerable importance for the paleoenvironmental reconstitution of South Tunisia at the end of the Upper Pleistocene. Grey or black silts and clays and greenish gray sands which overlap them, contain many paleontological remains: rodents, birds and Rhinoceros bones, Gasteropods, Foraminifera, Ostracoda and pollen. All these sedimentological, faunistic or botanical indications allow to consider that this area, between approximatively 35,000 and 22,000 yr. B.P., belonged to the steppe domaine. But this steppe was probably more dense and more diversified than the present-day steppe which receives 170 mm of rain (annual average). This conclusion is in good agreement with the other paleoenvironmental data from the Chott Djerid, the Matmata plateau or the Gulf of Gabès cores, areas situated at about 100 km to the West, the South or the East of the Oued el Akarit.

Aurora Mine project - historical resources baseline study

International Nuclear Information System (INIS)

Reeves, B.

1996-01-01

This volume contains the results of a base line archaeological study of the Aurora Mine Project local study area. It was compiled in support of Syncrude Canada's application to the Alberta Energy and Utilities Board (AEUB) and Alberta Environmental Protection to construct and operate it new Aurora Mine, located northeast of Fort McMurray, Alberta. The objective of this study was to compile, consolidate, review and analyze the reports for the area compiled over the past 22 years in and adjacent to the local study area (LSA), particularly those of now existing and Syncrude projects, and previously proposed Alsands and OSLO projects. The report is a summary of the human history in the area including pre-contact native archaeological sites, past archaeological studies, the Hinterland site pattern, post-contact native traditional sites, oil sands exploration/development related sites and paleontological sites in the subject area, and areas adjacent to it. 150 refs., 5 tabs., 43 figs

Emulating a crowded intracellular environment in vitro dramatically improves RT-PCR performance

International Nuclear Information System (INIS)

Lareu, Ricky R.; Harve, Karthik S.; Raghunath, Michael

2007-01-01

The polymerase chain reaction's (PCR) phenomenal success in advancing fields as diverse as Medicine, Agriculture, Conservation, or Paleontology is based on the ability of using isolated prokaryotic thermostable DNA polymerases in vitro to copy DNA irrespective of origin. This process occurs intracellularly and has evolved to function efficiently under crowded conditions, namely in an environment packed with macromolecules. However, current in vitro practice ignores this important biophysical parameter of life. In order to more closely emulate conditions of intracellular biochemistry in vitro we added inert macromolecules into reverse transcription (RT) and PCR. We show dramatic improvements in all parameters of RT-PCR including 8- to 10-fold greater sensitivity, enhanced polymerase processivity, higher specific amplicon yield, greater primer annealing and specificity, and enhanced DNA polymerase thermal stability. The faster and more efficient reaction kinetics was a consequence of the cumulative molecular and thermodynamic effects of the excluded volume effect created by macromolecular crowding

Understanding Global Change: A New Conceptual Framework To Guide Teaching About Planetary Systems And Both The Causes And Effects Of Changes In Those Systems

Science.gov (United States)

Levine, J.; Bean, J. R.

2016-12-01

Goals of the Next Generation Science Standards include understanding climate change and learning about ways to moderate the causes and mitigate the consequences of planetary-scale anthropogenic activities that interact synergistically to affect ecosystems and societies. The sheer number and scale of both causes and effects of global change can be daunting for teachers, and the lack of a clear conceptual framework for presenting this material usually leads educators (and textbooks) to present these phenomenon as a disjointed "laundry list." But an alternative approach is in the works. The Understanding Global Change web resource, currently under development at the UC Berkeley Museum of Paleontology, will provide educators with a conceptual framework, graphic models, lessons, and assessment templates for teaching NGSS-aligned, interdisciplinary, global change curricula. The core of this resource is an original informational graphic that presents and relates Earth's global systems, human and non-human factors that produce changes in those systems, and the effects of those changes that scientists can measure.

Progress to extinction: increased specialisation causes the demise of animal clades.

Science.gov (United States)

Raia, P; Carotenuto, F; Mondanaro, A; Castiglione, S; Passaro, F; Saggese, F; Melchionna, M; Serio, C; Alessio, L; Silvestro, D; Fortelius, M

2016-08-10

Animal clades tend to follow a predictable path of waxing and waning during their existence, regardless of their total species richness or geographic coverage. Clades begin small and undifferentiated, then expand to a peak in diversity and range, only to shift into a rarely broken decline towards extinction. While this trajectory is now well documented and broadly recognised, the reasons underlying it remain obscure. In particular, it is unknown why clade extinction is universal and occurs with such surprising regularity. Current explanations for paleontological extinctions call on the growing costs of biological interactions, geological accidents, evolutionary traps, and mass extinctions. While these are effective causes of extinction, they mainly apply to species, not clades. Although mass extinctions is the undeniable cause for the demise of a sizeable number of major taxa, we show here that clades escaping them go extinct because of the widespread tendency of evolution to produce increasingly specialised, sympatric, and geographically restricted species over time.

Tempo and mode in human evolution.

Science.gov (United States)

McHenry, H M

1994-01-01

The quickening pace of paleontological discovery is matched by rapid developments in geochronology. These new data show that the pattern of morphological change in the hominid lineage was mosaic. Adaptations essential to bipedalism appeared early, but some locomotor features changed much later. Relative to the highly derived postcrania of the earliest hominids, the craniodental complex was quite primitive (i.e., like the reconstructed last common ancestor with the African great apes). The pattern of craniodental change among successively younger species of Hominidae implies extensive parallel evolution between at least two lineages in features related to mastication. Relative brain size increased slightly among successively younger species of Australopithecus, expanded significantly with the appearance of Homo, but within early Homo remained at about half the size of Homo sapiens for almost a million years. Many apparent trends in human evolution may actually be due to the accumulation of relatively rapid shifts in successive species. PMID:8041697

On the origin of modern humans: Asian perspectives.

Science.gov (United States)

Bae, Christopher J; Douka, Katerina; Petraglia, Michael D

2017-12-08

The traditional "out of Africa" model, which posits a dispersal of modern Homo sapiens across Eurasia as a single wave at ~60,000 years ago and the subsequent replacement of all indigenous populations, is in need of revision. Recent discoveries from archaeology, hominin paleontology, geochronology, genetics, and paleoenvironmental studies have contributed to a better understanding of the Late Pleistocene record in Asia. Important findings highlighted here include growing evidence for multiple dispersals predating 60,000 years ago in regions such as southern and eastern Asia. Modern humans moving into Asia met Neandertals, Denisovans, mid-Pleistocene Homo , and possibly H. floresiensis , with some degree of interbreeding occurring. These early human dispersals, which left at least some genetic traces in modern populations, indicate that later replacements were not wholesale. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

EVIDENCE OF A GUADALUPIAN AGE FOR THE KHUFF FORMATION OF SOUTHEASTERN OMAN: PRELIMINARY REPORT

Directory of Open Access Journals (Sweden)

LUCIA ANGIOLINI

1998-11-01

Full Text Available The Guadalupian succession of the Huqf area (Sultanate of Oman represents a mega-sequence comprising the fluvial terrigenous Gharif Formation and the overlying marine Khuff Formation. The Khuff Fm. is subdivided into four members and is composed of marls and bioclastic limestones. The Khuff Fm. yields a rich fauna of brachiopods, conodonts, foraminifers, bivalves, gastropods, ostracods and cephalopods. The brachiopod fauna of the Khuff Fm. includes strophomenids, productids, orthids and terebratulids. The associated conodont fauna includes Hindeodus excavatus Behnken, Merrilina sp., M. praedivergens Kozur & Mostler, and Sweetina n. sp. (systematic descriptions of conodonts are given in the Paleontological Appendix. Foraminifers are represented by species of Miliolina and Rotaliina. The Khuff Fm. is given a Wordian age, based on brachiopods and conodonts. The depositional environment of the Khuff Fm. of southeastern Oman corresponds to the outer shelf of a large carbonate platform covering most of the Arabian Platform. The Khuff Fm. is interpreted as a major transgressive-regressive cycle related to differential subsidence. 

Petrographic, mineralogical, geochemical and paleo environmental characterization of radioactive anomaly associated to carbonate rocks from Jandaira formation of high cretaceous from Potiguar basin - Rio Grande do Norte - Brazil

International Nuclear Information System (INIS)

Matsuda, N.S.

1988-01-01

The Jandaira Formation (Turonian/Maastrichtian - Potiguar Basin, Brazil) presents an anomalous radioactive marker in the upper part of its carbonatic section. This marker of 3-20 m in thickness, comprises an area of about 3500 Km 2 and shows a radioactivity of 470 UAPI, against a background of 20 UAPI on the Gamma Ray Log. In the effort of characterizing this marker, petrological, mineralogical, geological and paleontological, analyses were made in ditch samples of selected 23 wells. This marker is composed by bioclastics packstones to mudstones, mainly constituted of planktonic and bentonic forams, deposited in relatively deep water. Chemical analysis of the P 205 richest samples, the ones show that they are also enriched on U, F, As, Cr, Cu, Mo, Ni, Pb, S, Se, V, Y, Yb and on all rare-earth elements. The origin of the radioactive anomaly is due to the presence of sedimentary phosphates (phosphorite) made-up of uraniferous coloform apatite. (author)

BENTHIC FORAMINIFERAL BIOSTRATIGRAPHY OF MALATYA OLIGO-MIOCENE SUCCESSION (EASTERN TAURIDS, EASTERN TURKEY

Directory of Open Access Journals (Sweden)

Fatma GEDİK

2015-10-01

Full Text Available The benthic foraminiferal biostratigraphy of Oligo-Miocene aged Muratlı and Petekkaya formations which crop out over wide regions around Akçadağ town, west of Malatya pro- vince in Eastern Taurids were revealed in this study. Systematical sampling was carried out in measured stratigraphical sections in four locations in order to perform stratigraphical and paleontological investigations. Benthic foraminifera taken from 182 hard rock samples were defined and three biozones were determined as; SBZ 21-22, belonging to Oligocene (Rupe- lian - Early Chattian, SBZ 23 (Late Chattian and SBZ 25 belonging to Lower Miocene in shallow marine deposits in the region. It was stated that the assemblage of planktic forami- nifer and nannoplankton which stratigraphically detected within Chattian - Burdigalian units in the succession most probably indicated Aquitanian age. Besides; Oligo-Miocene transition in the region was approved with this study based on biostratigraphical locations of benthic foraminiferal taxa.

Heterochronical patterns of evolution in the transitional stages of vertebrate classes.

Science.gov (United States)

Schad, W

1993-12-01

Transitional forms of the recent classes of vertebrates are only known in paleontology. The well described examples are: Eusthenopteron foordi (Crossopterygii), Ichthyostega and Acanthostega (Labyrinthodontia) between Osteichthyes and Amphibia, Seymouria baylorensis (Amphibiosaria) between Amphibia and Reptilia, Archaeopteryx lithographica (Archaeornithes) between Reptilia and Aves, and the mammal-like reptiles Pelycosauria, Therapsida and Cynodontia between Reptilia and Aves, and the description of their phylogenetical heterochronies in terms of peramorphosis and paedomorphosis shows the progressive role of the motorial, especially the locomotorial organ systems and their functions in comparison with the retarded evolution of the axial system, especially the skull and central nervous system. The evolution of the Hominidae shows the same rule. The evaluation of these transitional forms in their fossil context reveals them as inhabitants of biotopes situated in the border areas of coastal and shore landscapes of marine, brackish or fresh water. These biotopes have obviously favoured the innovations on the high taxonimic level of macro-evolutionary characteristics.

Elephants (and extinct relatives) as earth-movers and ecosystem engineers

Science.gov (United States)

Haynes, Gary

2012-07-01

Modern African elephants affect habitats and ecosystems in significant ways. They push over trees to feed on upper branches and often peel large sections of bark to eat. These destructive habits sometimes transform woody vegetation into grasslands. Systems of elephant trails may be used and re-used for centuries, and create incised features that extend for many kilometers on migration routes. Elephants, digging in search of water or mineral sediments, may remove several cubic meters of sediments in each excavation. Wallowing elephants may remove up to a cubic meter of pond sediments each time they visit water sources. Accumulations of elephant dung on frequented land surfaces may be over 2 kg per square meter. Elephant trampling, digging, and dust-bathing may reverse stratigraphy at archeological localities. This paper summarizes these types of effects on biotic, geomorphic, and paleontological features in modern-day landscapes, and also describes several fossil sites that indicate extinct proboscideans had very similar effects, such as major sediment disturbances.

Niels Stensen: a 17th century scientist with a modern view of brain organization.

Science.gov (United States)

Parent, André

2013-07-01

In 1665 the Danish scholar Niels Stensen (1638-1686) reached Paris, where he pronounced a discourse on brain anatomy that was to orient neuroscientists for years to come. In his lecture, Stensen rejected ancient speculations about animal spirits and criticized René Descartes and his followers who, despite a poor knowledge of brain anatomy, elaborated complex models to explain the multifaceted function of what he considered the principal organ of the human mind. He advocated the need for studying the brain through a comparative, developmental and pathological convergent approach and called for appropriate dissection methods and accurate illustrations. His own careful anatomical studies permitted him to precisely depict many brain structures. After pioneering works in paleontology and geology, he devoted himself to theology. In 1677 Stensen converted from Lutheranism to Catholicism and, while working relentlessly as a bishop and apostolic vicar in Northern Europe, he died in self-imposed poverty at age 48.

Progress to extinction: increased specialisation causes the demise of animal clades

Science.gov (United States)

Raia, P.; Carotenuto, F.; Mondanaro, A.; Castiglione, S.; Passaro, F.; Saggese, F.; Melchionna, M.; Serio, C.; Alessio, L.; Silvestro, D.; Fortelius, M.

2016-08-01

Animal clades tend to follow a predictable path of waxing and waning during their existence, regardless of their total species richness or geographic coverage. Clades begin small and undifferentiated, then expand to a peak in diversity and range, only to shift into a rarely broken decline towards extinction. While this trajectory is now well documented and broadly recognised, the reasons underlying it remain obscure. In particular, it is unknown why clade extinction is universal and occurs with such surprising regularity. Current explanations for paleontological extinctions call on the growing costs of biological interactions, geological accidents, evolutionary traps, and mass extinctions. While these are effective causes of extinction, they mainly apply to species, not clades. Although mass extinctions is the undeniable cause for the demise of a sizeable number of major taxa, we show here that clades escaping them go extinct because of the widespread tendency of evolution to produce increasingly specialised, sympatric, and geographically restricted species over time.

Unifying ecology and macroevolution with individual-based theory.

Science.gov (United States)

Rosindell, James; Harmon, Luke J; Etienne, Rampal S

2015-05-01

A contemporary goal in both ecology and evolutionary biology is to develop theory that transcends the boundary between the two disciplines, to understand phenomena that cannot be explained by either field in isolation. This is challenging because macroevolution typically uses lineage-based models, whereas ecology often focuses on individual organisms. Here, we develop a new parsimonious individual-based theory by adding mild selection to the neutral theory of biodiversity. We show that this model generates realistic phylogenies showing a slowdown in diversification and also improves on the ecological predictions of neutral theory by explaining the occurrence of very common species. Moreover, we find the distribution of individual fitness changes over time, with average fitness increasing at a pace that depends positively on community size. Consequently, large communities tend to produce fitter species than smaller communities. These findings have broad implications beyond biodiversity theory, potentially impacting, for example, invasion biology and paleontology. © 2015 The Authors. Ecology Letters published by John Wiley & Sons Ltd and CNRS.

Atlas of marine bony fish otoliths (Sagittae of Southeastern - Southern Brazil Part I: Gadiformes (Macrouridae, Moridae, Bregmacerotidae, Phycidae and Merlucciidae; Part II: Perciformes (Carangidae, Sciaenidae, Scombridae and Serranidae

Directory of Open Access Journals (Sweden)

Carmen Lucia Del Bianco Rossi-Wongtschowski

2014-01-01

Full Text Available The drawings, detailed pictures, precise descriptions and measurements that characterize otoliths must be made available for studies in various areas, including taxonomy, phylogeny, ecology, fisheries, paleontology, diversity, predator-prey relationships and modeling. The Collection of Teleostei Fish Otoliths of Southeastern-Southern Brazil (COSS-Brasil of IOUSP contains 45,000 pairs of otoliths from 210 species. This publication is the first in a series that will constitute an atlas of Teleostei otoliths for southeastern-southern Brazil and presents the results of the morphologic and morphometric analyses of 11 Gadiformes and 36 Perciformes species by means of the most commonly used features, measurements and indices. Three otoliths of each species were illustrated and photographed whenever possible. The frequency of occurrence was calculated for each characteristic by total length classes (TL, and the ontogenetic differences were analyzed (multiple χ2 test; significance 0.05. Morphometric analyses were conducted for each characteristic per total length (TL class and for the whole sample, and the ontogenetic differences were analyzed.

Fissile Material Disposition Program: Deep Borehole Disposal Facility PEIS data input report for direct disposal. Direct disposal of plutonium metal/plutonium dioxide in compound metal canisters. Version 3.0

Energy Technology Data Exchange (ETDEWEB)

Wijesinghe, A.M.; Shaffer, R.J.

1996-01-15

The US Department of Energy (DOE) is examining options for disposing of excess weapons-usable nuclear materials [principally plutonium (Pu) and highly enriched uranium (HEU)] in a form or condition that is substantially and inherently more difficult to recover and reuse in weapons production. This report is the data input report for the Programmatic Environmental Impact Statement (PEIS). The PEIS examines the environmental, safety, and health impacts of implementing each disposition alternative on land use, facility operations, and site infrastructure; air quality and noise; water, geology, and soils; biotic, cultural, and paleontological resources; socioeconomics; human health; normal operations and facility accidents; waste management; and transportation. This data report is prepared to assist in estimating the environmental effects associated with the construction and operation of a Deep Borehole Disposal Facility, an alternative currently included in the PEIS. The facility projects under consideration are, not site specific. This report therefore concentrates on environmental, safety, and health impacts at a generic site appropriate for siting a Deep Borehole Disposal Facility.

Biological response to climate change in the Arctic Ocean: The view from the past

Science.gov (United States)

Cronin, Thomas M.; Cronin, Matthew A.

2017-01-01

The Arctic Ocean is undergoing rapid climatic changes including higher ocean temperatures, reduced sea ice, glacier and Greenland Ice Sheet melting, greater marine productivity, and altered carbon cycling. Until recently, the relationship between climate and Arctic biological systems was poorly known, but this has changed substantially as advances in paleoclimatology, micropaleontology, vertebrate paleontology, and molecular genetics show that Arctic ecosystem history reflects global and regional climatic changes over all timescales and climate states (103–107 years). Arctic climatic extremes include 25°C hyperthermal periods during the Paleocene-Eocene (56–46 million years ago, Ma), Quaternary glacial periods when thick ice shelves and sea ice cover rendered the Arctic Ocean nearly uninhabitable, seasonally sea-ice-free interglacials and abrupt climate reversals. Climate-driven biological impacts included large changes in species diversity, primary productivity, species’ geographic range shifts into and out of the Arctic, community restructuring, and possible hybridization, but evidence is not sufficient to determine whether or when major episodes of extinction occurred.

Morphology of the achene in species of the genus Scleria P. Berg (Cyperaceae) present in Costa Rica

International Nuclear Information System (INIS)

Espinoza Morales, Lindsay Patricia

2014-01-01

The morphological characteristics and external morphology of the fruits from species of Scleria present in Costa Rica are analyzed and described, using light microscopy and scanning electron microscopy. A taxonomic key is elaborated to allow easy identification and differentiation of distinct species. A dichotomous key is made with the help of Delta-key program to distinguish 21 species of Scleria, taking into consideration the morphology of the achene. A dendrogram is performed with the species of Scleria using only the morphological characters of its achenes, through the statistical program Past 2.12 Paleontological Statistic. 15 achenes were analyzed by species obtained from specimens of the herbarium of the Universidad de Costa Rica, Instituto Nacional de Biodiversidad, Herbario Nacional and Organizacion para Estudios Tropicales. Digital photographs were taken of the full view of achene, the detail of the surface and inferior of fruit. The hypogynium and the cupola have been the morphological structures most important of Scleria in the country [es

Fissile Material Disposition Program: Deep Borehole Disposal Facility PEIS data input report for direct disposal. Direct disposal of plutonium metal/plutonium dioxide in compound metal canisters. Version 3.0

International Nuclear Information System (INIS)

Wijesinghe, A.M.; Shaffer, R.J.

1996-01-01

The US Department of Energy (DOE) is examining options for disposing of excess weapons-usable nuclear materials [principally plutonium (Pu) and highly enriched uranium (HEU)] in a form or condition that is substantially and inherently more difficult to recover and reuse in weapons production. This report is the data input report for the Programmatic Environmental Impact Statement (PEIS). The PEIS examines the environmental, safety, and health impacts of implementing each disposition alternative on land use, facility operations, and site infrastructure; air quality and noise; water, geology, and soils; biotic, cultural, and paleontological resources; socioeconomics; human health; normal operations and facility accidents; waste management; and transportation. This data report is prepared to assist in estimating the environmental effects associated with the construction and operation of a Deep Borehole Disposal Facility, an alternative currently included in the PEIS. The facility projects under consideration are, not site specific. This report therefore concentrates on environmental, safety, and health impacts at a generic site appropriate for siting a Deep Borehole Disposal Facility

Um Conto, uma Caixa e a Paleontologia: uma maneira lúdica de a alunos com Deficiência Auditiva

Directory of Open Access Journals (Sweden)

Mário André Trindade Dantas

2009-08-01

Full Text Available Teaching science to deaf-mute children has several limitations. In recent years, some techniques and resourceshave been presented to this public. However, many approaches still have to be done. The contact of thesestudents with science is made preferably by learning through the language of signals. The main objective of thepresent work is to encourage the use of the “tale and box” methodology as an efficient way to apply scientificknowledge for deaf-mute children. The tale was about Ema (deaf-mute children and her friends learning theimportance of Paleontology and fossils through the visit of a paleontologist to their school. The story was writtenin Portuguese Language, which was translated and adapted to the Brazilian Sign Language - LIBRAS. The storyhas been implemented in some classes of a deaf-mute care entity in Aracaju (Sergipe State, northeast Brazil.Such approach proved to be a valuable methodological tool on transmission of scientific information to deafmutechildren.

New porcellioidean gastropods from early Devonian of Royal Creek area, Yukon Territory, Canada, with notes on their early phylogeny

Science.gov (United States)

Fryda, J.; Blodgett, R.B.; Lenz, A.C.; Manda, S.

2008-01-01

This paper presents a description of new gastropods belonging to the superfamily Porcellioidea (Vetigastropoda) from the richly diverse Lower Devonian gastropod fauna of the Road River Formation in the Royal Creek area, Yukon Territory. This fauna belongs to Western Canada Province of the Old World Realm. The Pragian species Porcellia (Porcellia) yukonensis n. sp. and Porcellia (Paraporcellia) sp. represent the oldest presently known members of subgenera Porcellia (Porcellia) and Porcellia (Paraporcellia). Their simple shell ornamentation fits well with an earlier described evolutionary trend in shell morphology of the Porcellinae. Late Pragian to early Emsian Perryconcha pulchra n. gen. and n. sp. is the first member of the Porcellioidea bearing a row of tremata on adult teleoconch whorls. The occurrence of this shell feature in the Porcellioidea is additional evidence that the evolution of the apertural slit was much more complicated than has been proposed in classical models of Paleozoic gastropod evolution. Copyright ?? 2008, The Paleontological Society.

Nannoplankton malformation during the Paleocene-Eocene Thermal Maximum and its paleoecological and paleoceanographic significance

Science.gov (United States)

Bralower, Timothy J.; Self-Trail, Jean

2016-01-01

The Paleocene-Eocene Thermal Maximum (PETM) is characterized by a transient group of nannoplankton, belonging to the genus Discoaster. Our investigation of expanded shelf sections provides unprecedented detail of the morphology and phylogeny of the transient Discoasterduring the PETM and their relationship with environmental change. We observe a much larger range of morphological variation than previously documented suggesting that the taxa belonged to a plexus of highly gradational morphotypes rather than individual species. We propose that the plexus represents malformed ecophenotypes of a single species that migrated to a deep photic zone refuge during the height of PETM warming and eutrophication. Anomalously, high rates of organic matter remineralization characterized these depths during the event and led to lower saturation levels, which caused malformation. The proposed mechanism explains the co-occurrence of malformed Discoaster with pristine species that grew in the upper photic zone; moreover, it illuminates why malformation is a rare phenomenon in the paleontological record.

The “unknown” Greek Paleoenvironment: Curriculum Proposals through an Infusion Model for Elementary School, Using Ammonite Fossils

Directory of Open Access Journals (Sweden)

Stiliani FRAGOULI

2017-06-01

Full Text Available In this study we introduce an infusion model to “inject” ammonites and ammonite fossils in current subjects of Greek primary curriculum. Paleontology and mainly fossils attract more and more elementary students and teachers, yet in Greece this trend is solely about dinosaurs, despite the fact that the most common Greek fossils are not dinosaurs, but ammonites. Ammonites can be found in large population and diversity inside Greek rocks, as these rocks were part of Tethys΄ seafloor at their geological time. Apart from the informal sources of education, these science topics are excluded from elementary national curriculum, and leave the regional paleoenvironment and geological history practically “unknown” to students. Data collected through a pre-test study, in 558 students of 4th, 5th, and 6th grade confirmed the above belief. A post-test at the original sample, using an open ended questionnaire and students’ drawings, evaluated positively the infusion teaching model, whose core were the ammonite fossils.

The ecological origins of snakes as revealed by skull evolution.

Science.gov (United States)

Da Silva, Filipe O; Fabre, Anne-Claire; Savriama, Yoland; Ollonen, Joni; Mahlow, Kristin; Herrel, Anthony; Müller, Johannes; Di-Poï, Nicolas

2018-01-25

The ecological origin of snakes remains amongst the most controversial topics in evolution, with three competing hypotheses: fossorial; marine; or terrestrial. Here we use a geometric morphometric approach integrating ecological, phylogenetic, paleontological, and developmental data for building models of skull shape and size evolution and developmental rate changes in squamates. Our large-scale data reveal that whereas the most recent common ancestor of crown snakes had a small skull with a shape undeniably adapted for fossoriality, all snakes plus their sister group derive from a surface-terrestrial form with non-fossorial behavior, thus redirecting the debate toward an underexplored evolutionary scenario. Our comprehensive heterochrony analyses further indicate that snakes later evolved novel craniofacial specializations through global acceleration of skull development. These results highlight the importance of the interplay between natural selection and developmental processes in snake origin and diversification, leading first to invasion of a new habitat and then to subsequent ecological radiations.

Workshops Without Walls: broadening access to science around the world.

Directory of Open Access Journals (Sweden)

Betül K Arslan

2011-08-01

Full Text Available The National Aeronautics and Space Administration (NASA Astrobiology Institute (NAI conducted two "Workshops Without Walls" during 2010 that enabled global scientific exchange--with no travel required. The second of these was on the topic "Molecular Paleontology and Resurrection: Rewinding the Tape of Life." Scientists from diverse disciplines and locations around the world were joined through an integrated suite of collaborative technologies to exchange information on the latest developments in this area of origin of life research. Through social media outlets and popular science blogs, participation in the workshop was broadened to include educators, science writers, and members of the general public. In total, over 560 people from 31 US states and 30 other nations were registered. Among the scientific disciplines represented were geochemistry, biochemistry, molecular biology and evolution, and microbial ecology. We present this workshop as a case study in how interdisciplinary collaborative research may be fostered, with substantial public engagement, without sustaining the deleterious environmental and economic impacts of travel.

On the homology of the shoulder girdle in turtles.

Science.gov (United States)

Nagashima, Hiroshi; Sugahara, Fumiaki; Takechi, Masaki; Sato, Noboru; Kuratani, Shigeru

2015-05-01

The shoulder girdle in turtles is encapsulated in the shell and has a triradiate morphology. Due to its unique configuration among amniotes, many theories have been proposed about the skeletal identities of the projections for the past two centuries. Although the dorsal ramus represents the scapular blade, the ventral two rami remain uncertain. In particular, the ventrorostral process has been compared to a clavicle, an acromion, and a procoracoid based on its morphology, its connectivity to the rest of the skeleton and to muscles, as well as with its ossification center, cell lineage, and gene expression. In making these comparisons, the shoulder girdle skeleton of anurans has often been used as a reference. This review traces the history of the debate on the homology of the shoulder girdle in turtles. And based on the integrative aspects of developmental biology, comparative morphology, and paleontology, we suggest acromion and procoracoid identities for the two ventral processes. © 2014 Wiley Periodicals, Inc.

The Late Miocene paleogeography of the Amazon Basin and the evolution of the Amazon River system

Science.gov (United States)

Latrubesse, Edgardo M.; Cozzuol, Mario; da Silva-Caminha, Silane A. F.; Rigsby, Catherine A.; Absy, Maria Lucia; Jaramillo, Carlos

2010-05-01

On the basis of paleontological content (vertebrates and palynology) and facies analysis from river banks, road cuts, and three wells, we have assigned the uppermost levels of the Solimões Formation in western Amazonia, Brazil, to the Late Miocene. The vertebrate fossil record from outcropping sediments is assigned to the Huayquerian-Mesopotamian mammalian biozones, spanning 9-6.5 Ma. Additionally, we present results that demonstrate that deposits in Peruvian Amazonia attributed to Miocene tidal environments are actually fluvial sediments that have been misinterpreted (both environmentally and chronologically) by several authors. The entire Late Miocene sequence was deposited in a continental environment within a subsiding basin. The facies analysis, fossil fauna content, and palynological record indicate that the environment of deposition was dominated by avulsive rivers associated with megafan systems, and avulsive rivers in flood basins (swamps, lakes, internal deltas, and splays). Soils developed on the flatter, drier areas, which were dominated by grasslands and gallery forest in a tropical to subtropical climate. These Late Miocene sediments were deposited from westward of the Purus arch up to the border of Brazil with Peru (Divisor Ranges) and Bolivia (Pando block). Eastward of the Iquitos structural high, however, more detailed studies, including vertebrate paleontology, need to be performed to calibrate with more precision the ages of the uppermost levels of the Solimões Formation. The evolution of the basin during the late Miocene is mainly related to the tectonic behavior of the Central Andes (˜ 3°-15°S). At approximately 5 Ma, a segment of low angle of subduction was well developed in the Nazca Plate, and the deformation in the Subandean foreland produced the inland reactivation of the Divisor/Contamana Ranges and tectonic arrangements in the Eastern Andes. During the Pliocene southwestern Brazilian Amazonia ceased to be an effective sedimentary

High-Precision U-Pb Geochronology and Correlation: An example Using the Neoproterozic-Cambrian Transition

Science.gov (United States)

Bowring, S. A.; Grotzinger, J. P.; Amthor, J.; Martin, M. E.

2001-05-01

understanding the causes and effects of Neoproterozoic glaciations. The Cambrian-Precambrian boundary is generally associated with a negative shift in carbon values although global isochroneity has not yet been demonstrated and unconformities mark the boundary in many places. New data suggest an age of 542 Ma for the excursion and boundary in Oman; results from Namibia, Oman, and Siberia are all consistent with this result. It has yet to be demonstrated that the paleontologically defined boundary coincides with the isotopic shift or is globally isochronous. The emerging geochronological framework, when combined with integrated paleontological, chemostratigraphic, and geological data will allow detailed global correlation and evaluation of models that invoke both intrinsic and extrinsic triggers for evolution.

Arcosaurios (Crocodilia, Dinosauria del Cretácico superior de la Conca de Tremp (Lleida, España

Directory of Open Access Journals (Sweden)

Buscalioni, A. D.

1987-12-01

Full Text Available The study of a great part of the material found during the excavation work carried out by a team of the «Institut de Paleontología de Sabadell» and other paleontologists of the universities of Madrid and Bellaterra, in the basin of Tremp (Maastrichtiense in 1984 and 1985 has made possible the recognition of: 1.º A large sized Crocodilian, attributable to an adult animal of the Alligatoridae family, comparable to Crocodilus affluvelensis. 2.° Dinosaur remains atributed to three difIerent families: Atlantosauridae (represented by a large sized Sauropod, probably Hypselosaurus; Iguanodontidae (afI. Rhabdodon, medium sized Omithopod; and Hadrosauridae (Ortbomerus, small sized. 3.° Dinosaur's footprints, not very well preserved, medium and large sized, attributable to biped Omithopod. The fauna remains were always found unconnected, scattered all over large areas and with no signs of depredation. The sort of materials found reveal a certain transport which caused a selective action over the remains. Later, the efIects of the orogenic processes suffered by this area in the Tertiary period would combine with this transport.El estudio de gran parte del material hallado en los trabajos de excavación realizados por un equipo del «Institut de Paleontología de Sabadell» y otros paleontólogos de las Universidades de Madrid y Bellaterra, en la cuenca de Tremp (Maastrichtiense, durante los años 1984 y 1985, ha permitido reconocer: 1.º Un crocodílido de gran talla, atribuible a un animal adulto de la familia Alligatoridae, comparable a Crocodilus affluvelensis. 2.° Restos de dinosaurios que se han atribuido a tres familias: Atlantosauridae (representada por un saurópodo de gran talla, probablemente Hypselosaurus; Iguanodontidae (afI. Rhabdodon, ornitópodo de talla media, y Hadrosauridae (Ortbomerus, de talla pequeña. 3.° Icnitas de dinosaurios, bastante mal conservadas, de tamaño medio y grande, atribuibles a omit

Estratigrafía y paleontología del Cenozoico marino del Gran Bajo y Salinas del Gualicho, Argentina, y descripción de 17 especies nuevas Stratigraphy and Paleontology of the marine Cenozoic from the Gran Bajo and Salinas del Gualicho , Argentina and description of 17 new species

Directory of Open Access Journals (Sweden)

Valeria A Reichler

2010-01-01

Full Text Available La estratigrafía de la Formación Gran Bajo del Gualicho se presenta con mayor detalle, proponiéndose los nuevos Miembros Saladar y Arrióla, precisando la sucesión faunística integrada por 35 géneros y 41 especies, de las cuales 17 son nuevas y se describen en este estudio: Anadara australis sp. nov., Cubitostrea delrioi sp. nov, Amusium rorii sp. nov., Zygochlamys rizzoloi sp. nov,Pododesmus (Monia atlántica sp. nov, Tawera canalei sp. nov.,Dosinia (Dosinia salarensis sp. nov, 'Spirocolpus' adapicis sp. nov, Torcula magna sp. nov,Magnatica hansi sp. nov., Eudo-lium lissiei sp. nov, Sconsia magdai sp. nov., Chicoreus (Chicoreus guadalupei sp. nov, Penion patagonensis sp. nov, Mitra (Fusimitra carlosi sp. nov, Austroimbricaria brugnii sp. nov. y Polystira cingula sp. nov. El reconocimiento de la Asociación de Moluscos NVG (Nodipecten sp.-Venericor abasolensis-Glycymerita camaronesia sitúa al Membro Saladar nov. en el Moceno Temprano alto-Mioceno Medio bajo y lo correlaciona con la sección superior de la Formación Chenque y con los estratos portadores de Venericor de las formaciones Gaiman y Vaca Mahuida. La fauna de este miembro constituye una evidencia más respecto a la diferenciación en franjas climáticas postulada para Patagonia a partir del Oligoceno Tardío-Mioceno Temprano. En el Miembro Arrióla nov., la asociación recuperada indica probablemente la biozona de Aequipecten paranensis y su relación estratigráfica con la Formación Puerto Madryn del Moceno Tardío bajo, extendiendo el área abarcada por la Provincia Valdesiana hasta las Salinas del Gualicho. La fauna del Miembro Saladar presenta mayor afinidad con las que integran las formaciones Monte León y Chenque, mientras que la del Miembro Arrióla es más afín con las de las formaciones Puerto Madryn y Paraná. Las formaciones chilenas Navidad y Guadal presentan respectivamente el 30% y el 10% de los géneros en común con la fauna del Miembro Saladar.The stratigraphy of the Gran Bajo del Gualicho Formation is explained by the identification of the new Saladar and Arrióla Members. The molluscan fauna comprises 38 genera and 44 species, 17 of which are new: Anadara australis sp. nov, Cubitostrea delrioi sp. nov., Amusium rorii sp. nov, Zygochlamys rizzoloi sp. nov,Pododesmus (Monia atlántica sp. nov, Tawera canalei sp. nov,Dosinia (Dosinia salarensis sp. nov., 'Spirocolpuá adapicis sp. nov., Torcula magna sp. nov, Magnatica hansi sp. nov, Eudolium lissiei sp. nov, Sconsia magdai sp. nov, Chicoreus (Chicoreus guadalupei sp. nov., Penion patagonensis sp. nov., Mitra (Fusimitra carlosi sp. nov, Austroimbricaria brugnii sp. nov. y Polystira cingula sp. nov. The NVG (Nodipecten sp.-Venericor abasolensis- Glycymerita camaronesia Molluscan Assemblage in the Saladar Member nov. indicates an age of late Early Miocene-earliest Middle Miocene. The Saladar Member correlates with the upper section of the Chenque Formation and with the Venericorbeanng horizons of the Gaiman and Vaca Mahuida formations. The fauna of this member constitutes another evidence with respect to the weather stripes stated for Patagonia since the Late Oligocene-Early Mocene. The assemblage recorded in the Arrióla Member nov. indicates the probable presence of the Aequipecten parenensis Zone and a stratigraphic relationship with the Puerto Madryn Formation of a Late Mocene age, extending the covered área along the Valdesian Province to the Salinas del Gualicho. The fauna of the Saladar Member shows more affmity with that in the Monte León and Chenque formations, while the fauna in the Arrióla Member shares more resemblance with the Paraná and Puerto Madryn formations. The Chilean Navidad and Guadal formations have 30% and 10% of genus in common with fauna of the Saladar Member, respectively.

Extending and expanding the Darwinian synthesis: the role of complex systems dynamics.

Science.gov (United States)

Weber, Bruce H

2011-03-01

Darwinism is defined here as an evolving research tradition based upon the concepts of natural selection acting upon heritable variation articulated via background assumptions about systems dynamics. Darwin's theory of evolution was developed within a context of the background assumptions of Newtonian systems dynamics. The Modern Evolutionary Synthesis, or neo-Darwinism, successfully joined Darwinian selection and Mendelian genetics by developing population genetics informed by background assumptions of Boltzmannian systems dynamics. Currently the Darwinian Research Tradition is changing as it incorporates new information and ideas from molecular biology, paleontology, developmental biology, and systems ecology. This putative expanded and extended synthesis is most perspicuously deployed using background assumptions from complex systems dynamics. Such attempts seek to not only broaden the range of phenomena encompassed by the Darwinian Research Tradition, such as neutral molecular evolution, punctuated equilibrium, as well as developmental biology, and systems ecology more generally, but to also address issues of the emergence of evolutionary novelties as well as of life itself. Copyright © 2010 Elsevier Ltd. All rights reserved.

A new model for ancient DNA decay based on paleogenomic meta-analysis.

Science.gov (United States)

Kistler, Logan; Ware, Roselyn; Smith, Oliver; Collins, Matthew; Allaby, Robin G

2017-06-20

The persistence of DNA over archaeological and paleontological timescales in diverse environments has led to a revolutionary body of paleogenomic research, yet the dynamics of DNA degradation are still poorly understood. We analyzed 185 paleogenomic datasets and compared DNA survival with environmental variables and sample ages. We find cytosine deamination follows a conventional thermal age model, but we find no correlation between DNA fragmentation and sample age over the timespans analyzed, even when controlling for environmental variables. We propose a model for ancient DNA decay wherein fragmentation rapidly reaches a threshold, then subsequently slows. The observed loss of DNA over time may be due to a bulk diffusion process in many cases, highlighting the importance of tissues and environments creating effectively closed systems for DNA preservation. This model of DNA degradation is largely based on mammal bone samples due to published genomic dataset availability. Continued refinement to the model to reflect diverse biological systems and tissue types will further improve our understanding of ancient DNA breakdown dynamics. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Conference program and abstracts. International Biogeography Society 6th Biennial Meeting – 9-13 January 2013, Miami, Florida, USA

Directory of Open Access Journals (Sweden)

Joaquín Hortal

2012-12-01

Full Text Available Proceedings of the Sixth biennial conference of the International Biogeography Society, an international and interdisciplinary society contributing to the advancement of all studies of the geography of nature. Held at Miami, Florida, USA, 9 – 13 January 2013.Abstracts include:(i the Opening, MacArthur & Wilson Award and Alfred Russel Award Plenary Lectures;(ii four symposia entitled "Island Biogeography: New Syntheses", "Beyond Bergmann: New perspectives on the biogeography of traits", "The Convergence of Conservation Paleontology and Biogeography" and "Predicting species and biodiversity in a warmer world: are we doing a good job?";(iii oral presentations from contributed papers on Phylogeography, Marine Biogeography, Biogeography of the Anthropocene, Hot Topics in biogeography, Island Biogeography, Neotropical Biogeography, Global Change Biogeography, Historical and Paleo-biogeography, Conservation Biogeography and Global-Scale Biogeography; and(iv contributions presented as posters on Phylogeography, Geospatial techniques and land cover, Biodiversity gradients and macroecology, Biogeography of traits, Island Biogeography, Neotropical Biogeography, Conservation Biogeography, Disturbance and Disease Biogeography, Climate Change Biogeography and Historical and Paleo-Biogeography.

An overview of the Upper Carboniferous fossil deposit at Linton, Ohio

Energy Technology Data Exchange (ETDEWEB)

Hook, R.W.; Baird, D.

1988-03-01

The cannel coal that underlies the Upper Freeport coal (Westphalian D, Upper Carboniferous) at Linton in Jefferson County, Ohio, has yielded a remarkable fossil assemblage of at least 10 invertebrate taxa and nearly 40 vertebrate taxa. Spirorbid worms, crustaceans (primarily syncarids and conchostracans), and fishes (coelacanths, haplolepid palaeoniscoids, and xenacanth sharks) are the most abundant fossils in the deposit; small aquatic amphibians (including nectridean, temnospondyl, and aistopod species) are also common. Other arthropod and tetrapod taxa are exceedingly rare and possess obvious adaptations for terrestial existence. The fossiliferous cannel originated as the sapropelic filling of an approximately 15-m-deep abandoned river meander within an alluviated delta plain setting. Remains of animals that lived in and near the freshwater oxbow accumulated in this anaerobic, scavenger-free lake bottom. The assemblage is autochthonous at the scale of the floodplain lake and its margins and represents a lowland biocoenose. Previous paleoecological interpretations of the Linton assemblage and similar Westphalian vertebrate deposits cannot be upheld because they are based largely on paleontological inferences and incorrect paleoenvironmental diagnoses. 34 refs., 3 figs., 3 tabs.

Sedimentology and paleoecology of an Eocene Oligocene alluvial lacustrine arid system, Southern Mexico

Science.gov (United States)

Beraldi-Campesi, Hugo; Cevallos-Ferriz, Sergio R. S.; Centeno-García, Elena; Arenas-Abad, Concepción; Fernández, Luis Pedro

2006-10-01

A depositional model of the Eocene-Oligocene Coatzingo Formation in Tepexi de Rodríguez (Puebla, Mexico) is proposed, based on facies analysis of one of the best-preserved sections, the Axamilpa Section. The sedimentary evolution is interpreted as the retrogradation of an alluvial system, followed by the progressive expansion of an alkaline lake system, with deltaic, palustrine, and evaporitic environments. The analysis suggests a change towards more arid conditions with time. Fossils from this region, such as fossil tracks of artiodactyls, aquatic birds and cat-like mammals, suggest that these animals traversed the area, ostracods populated the lake waters, and plants grew on incipient soils and riparian environments many times throughout the history of the basin. The inferred habitat for some fossil plants coincides with the sedimentological interpretation of an arid to semiarid climate for that epoch. This combined sedimentological-paleontological study of the Axamilpa Section provides an environmental context in which fossils can be placed and brings into attention important biotic episodes, like bird and camelid migrations or the origin of endemic but extinct plants in this area.

Sex reduces genetic variation: a multidisciplinary review.

Science.gov (United States)

Gorelick, Root; Heng, Henry H Q

2011-04-01

For over a century, the paradigm has been that sex invariably increases genetic variation, despite many renowned biologists asserting that sex decreases most genetic variation. Sex is usually perceived as the source of additive genetic variance that drives eukaryotic evolution vis-à-vis adaptation and Fisher's fundamental theorem. However, evidence for sex decreasing genetic variation appears in ecology, paleontology, population genetics, and cancer biology. The common thread among many of these disciplines is that sex acts like a coarse filter, weeding out major changes, such as chromosomal rearrangements (that are almost always deleterious), but letting minor variation, such as changes at the nucleotide or gene level (that are often neutral), flow through the sexual sieve. Sex acts as a constraint on genomic and epigenetic variation, thereby limiting adaptive evolution. The diverse reasons for sex reducing genetic variation (especially at the genome level) and slowing down evolution may provide a sufficient benefit to offset the famed costs of sex. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

Current topics in ESR dating

International Nuclear Information System (INIS)

Skinner, Anne R.

2011-01-01

After over 25 years, the use of electron spin resonance (ESR) is well-established in dating sites of geological, paleontological and archaeological interest. Like any scientific technique, there have been changes in understanding and in methodology. Improvements have not, however, changed the observation that external dose calculations are still a significant source of uncertainty in ages. Examples from Europe, Africa and the Americans illustrate this point. For Pradayrol Cave (France), the occupation age, 330 ka, is unchallenged, making this the oldest known Neanderthal site in France. For Roc de Marsal, also in France, on the other hand, discrepancies between TL and sedimentary dose rates imply substantial differences in interpretation. In the Western Egyptian Desert, where artifacts and datable material are not well-correlated, the dating results show consistency with expectations based on global climate change, even in deflated sites. Climate change is also the question in geological studies in the Bahamas where, despite concerns about cosmic dose history, ESR dates confirm other evidence for sea level changes. We show that an uncertain age is not the same as an impossible one.

Mass Extinctions and Supernova Explosions

Science.gov (United States)

Korschinek, Gunther

A nearby supernova (SN) explosion could have negatively influenced life on Earth, maybe even been responsible for mass extinctions. Mass extinction poses a significant extinction of numerous species on Earth, as recorded in the paleontologic, paleoclimatic, and geological record of our planet. Depending on the distance between the Sun and the SN, different types of threats have to be considered, such as ozone depletion on Earth, causing increased exposure to the Sun's ultraviolet radiation or the direct exposure of lethal X-rays. Another indirect effect is cloud formation, induced by cosmic rays in the atmosphere which result in a drop in the Earth's temperature, causing major glaciations of the Earth. The discovery of highly intensive gamma-ray bursts (GRBs), which could be connected to SNe, initiated further discussions on possible life-threatening events in the Earth's history. The probability that GRBs hit the Earth is very low. Nevertheless, a past interaction of Earth with GRBs and/or SNe cannot be excluded and might even have been responsible for past extinction events.

High-resolution sedimentological and subsidence analysis of the Late Neogene, Pannonian Basin, Hungary

Science.gov (United States)

Juhasz, E.; Muller, P.; Toth-Makk, A.; Hamor, T.; Farkas-Bulla, J.; Suto-Szentai, M.; Phillips, R.L.; Ricketts, B.

1996-01-01

Detailed sedimentological and paleontological analyses were carried out on more than 13,000 m of core from ten boreholes in the Late Neogene sediments of the Pannonian Basin, Hungary. These data provide the basis for determining the character of high-order depositional cycles and their stacking patterns. In the Late Neogene sediments of the Pannonian Basin there are two third-order sequences: the Late Miocene and the Pliocene ones. The Miocene sequence shows a regressive, upward-coarsening trend. There are four distinguishable sedimentary units in this sequence: the basal transgressive, the lower aggradational, the progradational and the upper aggradational units. The Pliocene sequence is also of aggradational character. The progradation does not coincide in time in the wells within the basin. The character of the relative water-level curves is similar throughout the basin but shows only very faint similarity to the sea-level curve. Therefore, it is unlikely that eustasy played any significant role in the pattern of basin filling. Rather, the dominant controls were the rapidly changing basin subsidence and high sedimentation rates, together with possible climatic factors.

Census plan of environmental and cultural heritage of Latium Region. The Pontina and Fondi coastal plains; I beni culturali a carattere geologico del Lazio. La Pianura Pontina, Fondana e i Monti Ausoni meridionali

Energy Technology Data Exchange (ETDEWEB)

Casto, L. [Regione Lazio, Rome (Italy). Assessorato alle Politiche per la Promozione della Cultura, dello Spettacolo, del Turismo e dello Sport. Centro Regionale di Documentazione; Zarlenga, F. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente. Settore Informazione e Diffusione

1997-12-31

The geological heritage also indicated as `Geosites` or `Geotopes` in the `Area 4` defined in the Census Plan of Environmental and Cultural Heritage of Latium Region (Delivery R.C. n. 642/1979) in this paper is hereby described. In this area the Pontina and Fondi coastal plains, the Alban Hills Volcanic District Northward, the Mounts Volsci Range Eastward and Southward the Circeo Promontory is present. The geological context is described referring to the geomorphology and the landscape, the paleontology, the stratigraphy, the hydrogeology and the building materials. The museums set in the area also described. Geological history began during Upper Trias (Volsci Range and Circeo promontory) has continued until recent times (Pontina and Fondi plains and Alban Hills Volcanic District). The Mount Volsci Range is mostly constituted by carbonatic rocks (`Latium-Abruzzi series`) with shelf facies, ranging in age from the Upper Trias to the Paleocene, with scarce evidence of the Miocene transgression. From a structural point of view the Volsci chain shows main tectonic alignments trending NW-SE, NE-SW and N-S, folds and overthrusts verging NE.

First hominoid from the Late Miocene of the Irrawaddy Formation (Myanmar.

Directory of Open Access Journals (Sweden)

Jean-Jacques Jaeger

2011-04-01

Full Text Available For over a century, a Neogene fossil mammal fauna has been known in the Irrawaddy Formation in central Myanmar. Unfortunately, the lack of accurately located fossiliferous sites and the absence of hominoid fossils have impeded paleontological studies. Here we describe the first hominoid found in Myanmar together with a Hipparion (s.l. associated mammal fauna from Irrawaddy Formation deposits dated between 10.4 and 8.8 Ma by biochronology and magnetostratigraphy. This hominoid documents a new species of Khoratpithecus, increasing thereby the Miocene diversity of southern Asian hominoids. The composition of the associated fauna as well as stable isotope data on Hipparion (s.l. indicate that it inhabited an evergreen forest in a C3-plant environment. Our results enlighten that late Miocene hominoids were more regionally diversified than other large mammals, pointing towards regionally-bounded evolution of the representatives of this group in Southeast Asia. The Irrawaddy Formation, with its extensive outcrops and long temporal range, has a great potential for improving our knowledge of hominoid evolution in Asia.

Biofilms and Marine Invertebrate Larvae: What Bacteria Produce That Larvae Use to Choose Settlement Sites

Science.gov (United States)

Hadfield, Michael G.

2011-01-01

Communities of microorganisms form thin coats across solid surfaces in the sea. Larvae of many marine invertebrates use biofilm components as cues to appropriate settlement sites. Research on the tube-dwelling polychaete worm Hydroides elegans, a globally common member of biofouling communities, is described to exemplify approaches to understanding biofilm bacteria as a source of settlement cues and larvae as bearers of receptors for bacterial cues. The association of species of the bacterial genus Pseudoalteromonas with larval settlement in many phyla is described, and the question of whether cues are soluble or surface-bound is reviewed, concluding that most evidence points to surface-bound cues. Seemingly contradictory data for stimulation of barnacle settlement are discussed; possibly both explanations are true. Paleontological evidence reveals a relationship between metazoans and biofilms very early in metazoan evolution, and thus the receptors for bacterial cues of invertebrate larvae are very old and possibly unique. Finally, despite more than 60 years of intense investigation, we still know very little about either the bacterial ligands that stimulate larval settlement or the cellular basis of their detection by larvae.

Abstracts of the GAC-MAC annual meeting : planet Earth in Montreal

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

This joint meeting of the Geological Association of Canada and the Mineralogical Association of Canada addressed a range topical issues dealing with geosciences, with particular emphasis on resource exploration. The 6 sessions within the general session were entitled: (1) economic geology, (2) structural geology and tectonics, (3) mineralogy, crystallography and mineral chemistry, (4) igneous petrology, volcanology and metamorphic petrology, (5) sedimentology, paleontology and micropaleontology, and (6) miscellaneous issues. The challenges facing the Canadian geoscience community regarding greenhouse gases and global change were outlined along with new tools and technologies for mineral exploration. Lead isotopes as tracers of geological and environmental processes were discussed along with the stratigraphy and resource potential of the St. Lawrence Platform. Over a thousand specialists in Earth sciences from Canada, the United States and Europe participated in the general session as well as conference exhibits, symposia, special courses, workshops, poster sessions, field trips and an outreach program. Commercial, university and government displays were an integral part of the meeting. Six presentations from the conference have been catalogued separately for inclusion in this database.

Evidence for expansion of the precuneus in human evolution.

Science.gov (United States)

Bruner, Emiliano; Preuss, Todd M; Chen, Xu; Rilling, James K

2017-03-01

The evolution of neurocranial morphology in Homo sapiens is characterized by bulging of the parietal region, a feature unique to our species. In modern humans, expansion of the parietal surface occurs during the first year of life, in a morphogenetic stage which is absent in chimpanzees and Neandertals. A similar variation in brain shape among living adult humans is associated with expansion of the precuneus. Using MRI-derived structural brain templates, we compare medial brain morphology between humans and chimpanzees through shape analysis and geometrical modeling. We find that the main spatial difference is a prominent expansion of the precuneus in our species, providing further evidence of evolutionary changes associated with this area. The precuneus is a major hub of brain organization, a central node of the default-mode network, and plays an essential role in visuospatial integration. Together, the comparative neuroanatomical and paleontological evidence suggest that precuneus expansion is a neurological specialization of H. sapiens that evolved in the last 150,000 years that may be associated with recent human cognitive specializations.

The Upper Miocene Lake Pannon marl from the Filijala Open Pit (Beočin, northern Serbia: New geological and paleomagnetic data

Directory of Open Access Journals (Sweden)

Ganić Meri

2010-01-01

Full Text Available This work presents major lithological, structural, paleontological and paleomagnetic characteristics of the Upper Miocene Pannonian marl in the Filijala Open Pit of the La Farge Cement Plant near Beočin, northern Serbia. Pannonian marl lies between the underlying heterogeneous Sarmatian deposits and the overlying set of Pontian sand beds and Quaternary sediments. The open pit is located on the NE range of Fruška Gora, a horst structure with a core of Paleozoic, Mesozoic and Paleogene rocks in a complex structural pattern. Pannonian sediments, which are part of a younger structural stage, deposited on the horst limbs. The Pannonian marl strata dip at angles from 12° to 26° (to the NNW, forming a monocline. The strata deformations are a consequence of radial tectonics and are a potential source of landslides. The many mollusks (7 gastropod and 9 bivalve species and ostracodes (27 species and their biostratigraphical position indicate marl deposition throughout the Pannonian age. A paleomagnetic investigation established that the marl has inconsistent remanent magnetization (with bad statistical parameters, which originates from neoformed magnetite.

Biomechanical consequences of rapid evolution in the polar bear lineage.

Science.gov (United States)

Slater, Graham J; Figueirido, Borja; Louis, Leeann; Yang, Paul; Van Valkenburgh, Blaire

2010-11-05

The polar bear is the only living ursid with a fully carnivorous diet. Despite a number of well-documented craniodental adaptations for a diet of seal flesh and blubber, molecular and paleontological data indicate that this morphologically distinct species evolved less than a million years ago from the omnivorous brown bear. To better understand the evolution of this dietary specialization, we used phylogenetic tests to estimate the rate of morphological specialization in polar bears. We then used finite element analysis (FEA) to compare the limits of feeding performance in the polar bear skull to that of the phylogenetically and geographically close brown bear. Results indicate that extremely rapid evolution of semi-aquatic adaptations and dietary specialization in the polar bear lineage produced a cranial morphology that is weaker than that of brown bears and less suited to processing tough omnivorous or herbivorous diets. Our results suggest that continuation of current climate trends could affect polar bears by not only eliminating their primary food source, but also through competition with northward advancing, generalized brown populations for resources that they are ill-equipped to utilize.

Electron spin resonance dating of bones samples from recently excavated in Karnataka, India

International Nuclear Information System (INIS)

Ramamurthy, Ramya; Godhandabani, Velraj

2011-01-01

The study of radiation defects created in biomaterials, such as bone and teeth, can be used in dating with importance to paleontology and archaeology. A preliminary attempt has been made to date the bone samples from the archaeological site Gudnapur in Karnataka state, India. Each sample was divided into five sets which were given an artificial dose (AD) by using γ rays of 50 Gy, 300 Gy, 800 Gy and 1500 Gy and 3200 Gy. All the samples show similar EPR spectra having g-values 2.0026, 2.0025 and 2.0013 corresponding to CO 2 - orthorhombic and axial CO 2 - respectively. These signals have been used for the age estimation of the archaeological bone samples assuming the dose rate to be 1.12 mGy/a. The calculated ages of the samples are 199 ± 54 ka, 28 ± 23 ka and 225 ± 74 ka. The first and third correspond to the III interglacial stage whereas the second one corresponds to I glacial stage of the Pleistocene epoch respectively and in good agreement with age predicted by archaeological Department. (author)

Three-dimensional imaging of flat natural and cultural heritage objects by a Compton scattering modality

Science.gov (United States)

Guerrero Prado, Patricio; Nguyen, Mai K.; Dumas, Laurent; Cohen, Serge X.

2017-01-01

Characterization and interpretation of flat ancient material objects, such as those found in archaeology, paleoenvironments, paleontology, and cultural heritage, have remained a challenging task to perform by means of conventional x-ray tomography methods due to their anisotropic morphology and flattened geometry. To overcome the limitations of the mentioned methodologies for such samples, an imaging modality based on Compton scattering is proposed in this work. Classical x-ray tomography treats Compton scattering data as noise in the image formation process, while in Compton scattering tomography the conditions are set such that Compton data become the principal image contrasting agent. Under these conditions, we are able, first, to avoid relative rotations between the sample and the imaging setup, and second, to obtain three-dimensional data even when the object is supported by a dense material by exploiting backscattered photons. Mathematically this problem is addressed by means of a conical Radon transform and its inversion. The image formation process and object reconstruction model are presented. The feasibility of this methodology is supported by numerical simulations.

Completion Report for Well Cluster ER-6-1

Energy Technology Data Exchange (ETDEWEB)

Bechtel Nevada

2004-10-01

Well Cluster ER-6-1 was constructed for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Nevada Environmental Restoration Division at the Nevada Test Site, Nye County, Nevada. This work was initiated as part of the Groundwater Characterization Project, now known as the Underground Test Area Project. The well cluster is located in southeastern Yucca Flat. Detailed lithologic descriptions with stratigraphic assignments for Well Cluster ER-6-1 are included in this report. These are based on composite drill cuttings collected every 3 meters and conventional core samples taken below 639 meters, supplemented by geophysical log data. Detailed petrographic, chemical, and mineralogical studies of rock samples were conducted on 11 samples to resolve complex interrelationships between several of the Tertiary tuff units. Additionally, paleontological analyses by the U.S. Geological Survey confirmed the stratigraphic assignments below 539 meters within the Paleozoic sedimentary section. All three wells in the Well ER-6-1 cluster were drilled within the Quaternary and Tertiary alluvium section, the Tertiary volcanic section, and into the Paleozoic sedimentary section.

The fossil record of evolution: Analysis of extinction

Science.gov (United States)

Raup, D. M.

1986-01-01

There is increasing evidence that events in space have had direct effects on Earth history and on the history of life on Earth. Nowhere is this more evident than in mass extinction. The biosphere has undergone repeated devastation caused by relatively short-lived environmental stress, with species kill rates up to 80 and 95%. For five of the mass extinctions, geochemical or other evidence was reported suggesting large body impact as the cause of the environmental stress producing the extinctions. It was argued on statistical ground that the major extinction events are uniformly periodic in geological time. If it is true that large body impact is a principal cause of mass extinctions and if the periodicity is real, than a cosmic driving mechanism is inescapable. Paleontological data sets were developed which detail the ranges in geological time of about 4,000 families and 25,000 genera of fossil marine organisms. Analyses to date have concentrated on the most recent 250 million years. Associated with these studies are analyses of other aspects of Earth history which may have signatures indicative of extraterrestrial effects.

Two types of bone necrosis in the Middle Triassic Pistosaurus longaevus bones: the results of integrated studies

Science.gov (United States)

Surmik, Dawid; Rothschild, Bruce M.; Dulski, Mateusz; Janiszewska, Katarzyna

2017-07-01

Avascular necrosis, diagnosed on the basis of either a specific pathological modification of the articular surfaces of bone or its radiologic appearance in vertebral centra, has been recognized in many Mesozoic marine reptiles as well as in present-day marine mammals. Its presence in the zoological and paleontologic record is usually associated with decompression syndrome, a disease that affects secondarily aquatic vertebrates that could dive. Bone necrosis can also be caused by infectious processes, but it differs in appearance from decompression syndrome-associated aseptic necrosis. Herein, we report evidence of septic necrosis in the proximal articular surface of the femur of a marine reptile, Pistosaurus longaevus, from the Middle Triassic of Poland and Germany. This is the oldest recognition of septic necrosis associated with septic arthritis in the fossil record so far, and the mineralogical composition of pathologically altered bone is described herein in detail. The occurrence of septic necrosis is contrasted with decompression syndrome-associated avascular necrosis, also described in Pistosaurus longaevus bone from Middle Triassic of Germany.

Developmental changes in the skull morphology of common minke whales Balaenoptera acutorostrata.

Science.gov (United States)

Nakamura, Gen; Kato, Hidehiro

2014-10-01

We investigated growth-related and sex-related morphological changes in the skulls of 144 North Pacific common minke whales Balaenoptera acutorostrata. Measurement was conducted at 39 points on the skull and mandible to extract individual allometric equations relating the length and zygomatic width of the skull. The results revealed no significant differences in skull morphology by sex except for width of occipital bone. The size relative to the skull of the anatomical parts involved in feeding, such as the rostrum and mandible, increased after birth. In contrast, the sensory organs and the anatomical regions involved in neurological function, such as the orbit, tympanic bullae, and foramen magnum, were fully developed at birth, and their relative size reduced over the course of development. This is the first study to investigate developmental changes in the skull morphology using more than 100 baleen whale specimens, and we believe the results of this study will contribute greatly to multiple areas of baleen whale research, including taxonomy and paleontology. © 2014 Wiley Periodicals, Inc.

Profesor gerardo botero arango y la paleontología de colombia. intento de aproximación a las razones de su obra

OpenAIRE

ETAYO SERNA, FERNANDO

2008-01-01

El Profesor Gerardo Botero Arango pudo recibir el influjo del ideario berkeliano durante sus estudios universitarios, pero fue su actitud frente a las dificultades del trabajo de geología en Colombia, las mismas que vivimos hoy en día, lo que dio a su obra señas permanentes.

Paleontology, sedimentology and paleoenvironment of a new fossiliferous locality of the Jurassic Cañadón Asfalto Formation, Chubut Province, Argentina

Science.gov (United States)

Gallego, Oscar F.; Cabaleri, Nora G.; Armella, Claudia; Volkheimer, Wolfgang; Ballent, Sara C.; Martínez, Sergio; Monferran, Mateo D.; Silva Nieto, Diego G.; Páez, Manuel A.

2011-02-01

A new Late Jurassic assemblage of “conchostracans”, ostracods, bivalves and caddisfly cases from the locality “Estancia La Sin Rumbo”, Chubut Province (Patagonia, Argentina) is recorded. The fossils occur in the upper part of an outcropping 45 m thick volcaniclastic lacustrine sequence of yellowish tuffs and tuffites of the Puesto Almada Member, which is the upper member of the Cañadón Asfalto Formation with U/Pb age of 161 ± 3 Ma. The sequence represents one sedimentary cycle composed of a (lower) hemicycle of expansion and a (higher) hemicycle of contraction of the water body. The invertebrates lived in small freshwater bodies during the periods of expansion of the lake. The occurrence of a great number of small spinicaudatans, associated with mud-cracks, is evidence of dry climatic conditions and suggests several local mortality events. The spinicaudatan record of the fushunograptid-orthestheriid (component of the Eosestheriopsis dianzhongensis fauna) and the presence of Congestheriella rauhuti Gallego and Shen, suggest a Late Jurassic (Oxfordian to Tithonian) age. Caddisfly cases are recorded for the first time in the Cañadón Asfalto Basin.

Paleontología y bioestratigrafía del Mioceno continental de la cuenca de Calatayud (Zaragoza): Nuevos yacimientos de Micromamíferos

OpenAIRE

Sesé, Carmen

2003-01-01

Resumen: Se dan a conocer cinco nuevos yacimientos de micromamíferos de la cuenca de Calatayud: Vilueña, Torralba de Ribota 8, Montón, Armantes 14 y Belmonte, que abarcan un período comprendido entre el Mioceno inferior y el superior. En las asociaciones faunísticas de micromamíferos de los cuatro primeros yacimientos, hemos determinado la línea evolutiva de las especies: Megacricetodon primitivus-collongensis- crusafonti del Mioceno medio, lo que nos ha permitido situarlas con gr...

The Armenian and NW Anatolian ophiolites: new insights for the closure of the Tethys domain and obduction onto the South Armenian Block and Anatolian-Tauride Platform before collision through dynamic modeling

Science.gov (United States)

Hässig, Marc; Rolland, Yann; Sosson, Marc; Hassani, Riad; Topuz, Gultekin; Faruk Çelik, Ömer; Gerbault, Muriel; Galoyan, Ghazar; Müller, Carla; Sahakyan, Lilit; Avagyan, Ara

2013-04-01

In the Lesser Caucasus three main domains are distinguished from SW to NE: (1) the South Armenian Block (SAB), a Gondwanian-derived continental terrane; (2) scattered outcrops of ophiolites coming up against the Sevan-Akera suture zone; and (3) the Eurasian plate. The Armenian ophiolites represent remnants of an oceanic domain which disappeared during Eurasia-Arabia convergence. Previous works using geochemical whole-rock analyses, 40Ar/39Ar and paleontological dating have shown that the ophiolite outcrops throughout this area were emplaced during the Late Cretaceous as one non-metamorphic preserved ophiolitic nappe of back-arc origin that formed during Middle to Late Jurassic. From these works, tectonic reconstructions include two clearly identified subductions, one related to the Neotethys subduction beneath the Eurasian margin and another to intra-oceanic subduction responsible for the opening of the back-arc basin corresponding to the ophiolites of the Lesser Caucasus. The analysis of the two stages of metamorphism of the garnet amphibolites of the ophiolite obduction sole at Amasia (M1: HT-LP peak of P = 6-7 kbar and T > 630°C; M2; MP-MT peak at P = 8-10 kbar and T = 600°C) has allowed us to deduce the onset of subduction of the SAB at 90 Ma for this locality, which age coincides with other paleontological ages at the obduction front. A preliminary paleomagnetic survey has also brought quantification to the amount of oceanic domain which disappeared by subduction between the SAB and Eurasia before collision. We propose a dynamic finite element model using ADELI to test the incidence of parameters such as the density of the different domains (or the interval between the densities), closing speed (or speeds if sporadic), the importance and interactions of mantle discontinuities with the subducting lithosphere and set a lithospheric model. Our field observations and analyses are used to validate combinations of factors. The aim is to better qualify the

Water-Level Reconstruction and its Implications for Late Pleistocene Paleontological Site Formation in Hoyo Negro, a Submerged Subterranean Pit in Quintana Roo, Mexico

Science.gov (United States)

Rissolo, D.; Reinhardt, E. G.; Collins, S.; Kovacs, S. E.; Beddows, P. A.; Chatters, J. C.; Nava Blank, A.; Luna Erreguerena, P.

2014-12-01

A massive pit deep within the now submerged cave system of Sac Actun, located along the central east coast of the Yucatan Peninsula, contains a diverse fossil assemblage of extinct megafauna as well as a nearly complete human skeleton. The inundated site of Hoyo Negro presents a unique and promising opportunity for interdisciplinary Paleoamerican and paleoenvironmental research in the region. Investigations have thus far revealed a range of associated features and deposits which make possible a multi-proxy approach to identifying and reconstructing the natural and cultural processes that have formed and transformed the site over millennia. Understanding water-level fluctuations (both related to, and independent from, eustatic sea level changes), with respect to cave morphology is central to understanding the movement of humans and animals into and through the cave system. Recent and ongoing studies involve absolute dating of human, faunal, macrobotanical, and geological samples; taphonomic analyses; and a characterization of site hydrogeology and sedimentological facies, including microfossil assemblages and calcite raft deposits.

Statistically significant faunal differences among Middle Ordovician age, Chickamauga Group bryozoan bioherms, central Alabama

Energy Technology Data Exchange (ETDEWEB)

Crow, C.J.

1985-01-01

Middle Ordovician age Chickamauga Group carbonates crop out along the Birmingham and Murphrees Valley anticlines in central Alabama. The macrofossil contents on exposed surfaces of seven bioherms have been counted to determine their various paleontologic characteristics. Twelve groups of organisms are present in these bioherms. Dominant organisms include bryozoans, algae, brachiopods, sponges, pelmatozoans, stromatoporoids and corals. Minor accessory fauna include predators, scavengers and grazers such as gastropods, ostracods, trilobites, cephalopods and pelecypods. Vertical and horizontal niche zonation has been detected for some of the bioherm dwelling fauna. No one bioherm of those studied exhibits all 12 groups of organisms; rather, individual bioherms display various subsets of the total diversity. Statistical treatment (G-test) of the diversity data indicates a lack of statistical homogeneity of the bioherms, both within and between localities. Between-locality population heterogeneity can be ascribed to differences in biologic responses to such gross environmental factors as water depth and clarity, and energy levels. At any one locality, gross aspects of the paleoenvironments are assumed to have been more uniform. Significant differences among bioherms at any one locality may have resulted from patchy distribution of species populations, differential preservation and other factors.

The 'other faunivory' revisited: Insectivory in human and non-human primates and the evolution of human diet.

Science.gov (United States)

McGrew, William C

2014-06-01

The role of invertebrates in the evolution of human diet has been under-studied by comparison with vertebrates and plants. This persists despite substantial knowledge of the importance of the 'other faunivory', especially insect-eating, in the daily lives of non-human primates and traditional human societies, especially hunters and gatherers. Most primates concentrate on two phyla, Mollusca and Arthropoda, but of the latter's classes, insects (especially five orders: Coleoptera, Hymenoptera, Isoptera, Lepidoptera, Orthoptera) are paramount. An insect product, bees' honey, is particularly important, and its collection shows a reversal of the usual sexual division of labor. Human entomophagy involves advanced technology (fire, containers) and sometimes domestication. Insectivory provides comparable calorific and nutritional benefits to carnivory, but with different costs. Much insectivory in hominoids entails elementary technology used in extractive foraging, such as termite fishing by chimpanzees. Elucidating insectivory in the fossil and paleontological record is challenging, but at least nine avenues are available: remains, lithics, residues, DNA, coprolites, dental microwear, stable isotopes, osteology, and depictions. All are in play, but some have been more successful so far than others. Copyright © 2013 Elsevier Ltd. All rights reserved.

Creation, Visualization and 3D Printing of Online Collections of Three Timensional Educative Models with Low-Cost Technologies. Practical Case of Canarian Marine Fossil Heritage

Directory of Open Access Journals (Sweden)

Jose Luis SAORIN PÉREZ

2016-12-01

Full Text Available In many educational settings, the use of tangible objects is used to enhance learning (models, replicas of art works, fossils.... When knowledge is disseminated through virtual environments, sometimes, the value of these tangible objects is lost. The new low-cost technologies allow solving this problem, enabling teachers to include in their virtual classroom the access and manipulation of threedimensional objects. This article describes the process of creation and dissemination of a three-dimensional, interactive educational content for learning in a virtual environment. As a practical study, we have worked on the Canary marine fossil heritage. The fossils are used as tangible material in paleontology teaching, however they are not available for work outside the classroom. For this work, it has been digitized in 3D a selection of 18 fossils. 3D files obtained are available to students in an online environment, allowing download, multi-touch display and interaction on mobile devices. In addition, if the student prefers, they can print them using a 3D printer. Finally, there has been an experience with 70 university students who, after accessing to the online files, responded to a questionnaire to assess the made materials.

On the purposes of color for living beings: toward a theory of color organization.

Science.gov (United States)

Pinna, Baingio; Reeves, Adam

2015-01-01

Phylogenetic and paleontological evidence indicates that in the animal kingdom the ability to perceive colors evolved independently several times over the course of millennia. This implies a high evolutionary neural investment and suggests that color vision provides some fundamental biological benefits. What are these benefits? Why are some animals so colorful? What are the adaptive and perceptual meanings of polychromatism? We suggest that in addition to the discrimination of light and surface chromaticity, sensitivity to color contributes to the whole, the parts and the fragments of perceptual organization. New versions of neon color spreading and the watercolor illusion indicate that the visual purpose of color in humans is threefold: to inter-relate each chromatic component of an object, thus favoring the emergence of the whole; to support a part-whole organization in which components reciprocally enhance each other by amodal completion; and, paradoxically, to reveal fragments and hide the whole-that is, there is a chromatic parceling-out process of separation, division, and fragmentation of the whole. The evolution of these contributions of color to organization needs to be established, but traces of it can be found in Harlequin camouflage by animals and in the coloration of flowers.

Lipovitellin-phosvitin crystals with orthorhombic features: thin-section electron microscopy, gel electrophoresis, and microanalysis in teleost and amphibian yolk platelets and a comparison with other vertebrates

International Nuclear Information System (INIS)

Lange, R.H.; Richter, H.P.; Riehl, R.; Zierold, K.; Trandaburu, T.; Magdowski, G.

1983-01-01

Yolk-platelet crystals in the teleosts Pelvicachromis pulcher and Noemacheilus barbatulus and the amphibians Xenopus laevis, Rana temporaria, R. esculenta, and Triturus sp. have been studied by electron diffraction and imaging using a standardized processing (glutaraldehyde-osmium tetroxide fixation, glutaraldehyde-urea embedding, thin-section staining), by X-ray microanalysis, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of their constituents. The crystal lattice is orthorhombic having. Crystal images in the three axial projections point to the presence of space group P212121 (or an approximation of it since the lipovitellin dimers cannot be fully equivalent in some cases), to differences between the phosvitins of the two teleosts, and to a highly unusual stain exclusion from large crystal constituents interpreted as representing lipovitellin dimers. Microanalysis in ultrathin cryosections and other preparations revealed K and Cl to be the prominent ions in the crystals (and in the superficial layer of the platelet). Gel electrophoresis (including data of cyclostomes) showed considerable molecular variations despite a closely similar crystal architecture, emphasizing a physiological significance of the architecture, which may have remained conserved for nearly 400 million years according to paleontologic views

Holocene paleoclimatic variation in the Schirmacher Oasis, East Antarctica: A mineral magnetic approach

Science.gov (United States)

Phartiyal, Binita

2014-12-01

An analysis of remanent magnetism and radiocarbon ages in the dry lacustrine/sediment fills of the Schirmacher Oasis (SO) in East Antarctica was conducted to reconstruct past climatic condition. The statistically run mineral magnetic data on paleontological statistics software package (multivariate cluster analysis) placed on accelerator mass spectrometer radiocarbon chronology of the three sediment sections, trace 6 phases of climatic fluctuation between 13 and 3 ka, (Phases 1, 3 and 5 represent cold periods while Phases 2, 4, and 6 represent warm periods). One short warm period (Phase 2, ca. 12.5 ka) occurred in the late Pleistocene, and two marked warm periods (Phase 4, 11-8.7 ka; Phase 6, 4.4-3 ka) occurred in the Holocene. High magnetic susceptibility (χ), saturation isothermal remanent magnetism (SIRM), and soft isothermal remanent magnetism (soft IRM) values correspond to colder periods and low values reflect comparatively warmer lacustrine phases. Holocene Optima (Phase 4) and Mid Holocene Hypsithermal (Phase 6) are distinguished by decreased values of concentrations dependent parameters. Remanence is preserved in the low-coercive minerals. Heavy metals in the sediments include, Fe, Rb, Zn, Mo, Co, Pb, Mn, Cu, and As in order of decreasing abundance.

Large mammals from the Upper Neopleistocene reference sections in the Tunka rift valley, southwestern Baikal Region

Science.gov (United States)

Shchetnikov, A. A.; Klementiev, A. M.; Filinov, I. A.; Semeney, E. Yu.

2015-03-01

This work presents the data on new finds of fossil macrotheriofauna in the reference sections of the Upper Neopleistocene sediments in the Tunka rift valley (southwestern Baikal Region). The osteological material of a number of Late Neopleistocene mammals including extinct species rare for the Baikal region such as Crocuta spelaea, Panthera spelaea, and Spirocerus kiakhtensis (?) was directly dated with a radiocarbon (AMS) method. The obtained 14C data (18000-35000 years) allow one to rejuvenate significantly the upper limit of the common age interval of habitat of these animals in southern part of Eastern Siberia. Cave hyena and spiral-horned antelope lived in the Tunka rift valley in the Baikal region in Late Kargino time (37-24 ka), and cave lion survived the maximum in the Sartan cryochron in the region (21-20 ka). The study of collected paleontological collections provides a basis for selection of independent Kargino (MIS 3) faunal assemblages to use them for regional biostratigraphic analysis of Pleistocene deposits. Radiocarbon age dating of samples allows one to attribute confidently all paleofaunal remains available to the second half of the Late Pleistocene.

A new theropod dinosaur from India with remarks on the Gondwana-Laurasia connection in the Late Triassic

Science.gov (United States)

Chatterjee, S.

Walkeria maleriensis (n. g., n. sp.) from the Late Triassic Maleri Formation of the Godavari Valley of India is the earliest known dinosaur from Asia. It is a small podokesaurid theropod, very similar to Procompsognathus of Germany, Coelophysis of North America, and Syntarsus from Zimbabwe and North America. The podokesaurs are of particular interest to students of organic evolution because they are the earliest known theropods from which Archaeopteryx, the oldest known fossil bird, was probably evolved. Traditionally, India has been regarded as a part of Gondwana. It is generally believed that Gondwana remained an integral geographic unit throughout the Triassic. If this is so, a strong faunal correlation between India and other Gondwana continents should be expected in Late Triassic time. Contrary to this, the Maleri fauna is overwhelmingly "northern". Walkeria occurs in association with metoposaurs, parasuchids, protorosaurs, aetosaurs, rhynchosaurs, and traversodonts. Most of these taxa have been identified in the Dockum fauna of North America, indicating a close paleontologic link between India and Laurasia. Possibly the route of faunal migration between India and North America during the Late Triassic was via northern Africa.

Variation, Variability, and the Origin of the Avian Endocranium: Insights from the Anatomy of Alioramus altai (Theropoda: Tyrannosauroidea)

Science.gov (United States)

Bever, Gabe S.; Brusatte, Stephen L.; Balanoff, Amy M.; Norell, Mark A.

2011-01-01

The internal braincase anatomy of the holotype of Alioramus altai, a relatively small-bodied tyrannosauroid from the Late Cretaceous of Mongolia, was studied using high-resolution computed tomography. A number of derived characters strengthen the diagnosis of this taxon as both a tyrannosauroid and a unique, new species (e.g., endocranial position of the gasserian ganglion, internal ramification of the facial nerve). Also present are features intermediate between the basal theropod and avialan conditions that optimize as the ancestral condition for Coelurosauria—a diverse group of derived theropods that includes modern birds. The expression of several primitive theropod features as derived character states within Tyrannosauroidea establishes previously unrecognized evolutionary complexity and morphological plasticity at the base of Coelurosauria. It also demonstrates the critical role heterochrony may have played in driving patterns of endocranial variability within the group and potentially reveals stages in the evolution of neuroanatomical development that could not be inferred based solely on developmental observations of the major archosaurian crown clades. We discuss the integration of paleontology with variability studies, especially as applied to the nature of morphological transformations along the phylogenetically long branches that tend to separate the crown clades of major vertebrate groups. PMID:21853125

GIS representation of coal-bearing areas in Antarctica

Science.gov (United States)

Merrill, Matthew D.

2016-03-11

Understanding the distribution of coal-bearing geologic units in Antarctica provides information that can be used in sedimentary, geomorphological, paleontological, and climatological studies. This report is a digital compilation of information on Antarctica’s coal-bearing geologic units found in the literature. It is intended to be used in small-scale spatial geographic information system (GIS) investigations and as a visual aid in the discussion of Antarctica’s coal resources or in other coal-based geologic investigations. Instead of using spatially insignificant point markers to represent large coal-bearing areas, this dataset uses polygons to represent actual coal-bearing lithologic units. Specific locations of coal deposits confirmed from the literature are provided in the attribution for the coal-bearing unit polygons. Coal-sample-location data were used to confirm some reported coal-bearing geology. The age and extent of the coal deposits indicated in the literature were checked against geologic maps ranging from local scale at 1:50,000 to Antarctic continental scale at 1:5,000,000; if satisfactory, the map boundaries were used to generate the polygons for the coal-bearing localities.

Late Cretaceous paleosols as paleoclimate proxies of high-latitude Southern Hemisphere: Mata Amarilla Formation, Patagonia, Argentina

Science.gov (United States)

Varela, Augusto N.; Raigemborn, M. Sol; Richiano, Sebastián; White, Tim; Poiré, Daniel G.; Lizzoli, Sabrina

2018-01-01

Although there is general consensus that a global greenhouse climate characterized the mid-Cretaceous, details of the climate state of the mid-Cretaceous Southern Hemisphere are less clearly understood. In particular, continental paleoclimate reconstructions are scarce and exclusively derived from paleontological records. Using paleosol-derived climofunction studies of the mid- to Upper Cretaceous Mata Amarilla Formation, southern Patagonia, Argentina, we present a reconstruction of the mid-Cretaceous climate of southern South America. Our results indicate that at 60° south paleolatitude during the Cenomanian-Santonian stages, the climate was subtropical temperate-warm (12 °C ± 2.1 °C) and humid (1404 ± 108 mm/yr) with marked rainfall seasonality. These results are consistent with both previous estimations from the fossil floras of the Mata Amarilla Formation and other units of the Southern Hemisphere, and with the previous observations of the displacement of tropical and subtropical floras towards the poles in both hemispheres. The data presented here show a more marked seasonality and slightly lower mean annual precipitation and mean annual temperature values than those recorded at the same paleolatitudes in the Northern Hemisphere.

Didelphidae marsupials (Mammalia, Didelphimorphia from the Late Pleistocene deposit of the Gruta dos Moura Cave, northern Brazil

Directory of Open Access Journals (Sweden)

Patricia Villa Nova

2015-03-01

Full Text Available The present study acknowledges the diversity of fossil marsupials from the Gruta dos Moura cave, as well as environmental and climatic aspects during the Quaternary. The results show that this is the largest diversity of Pleistocene marsupials recorded in a single cave: Didelphis albiventris, D. aurita, Gracilinanus agilis, G. microtarsus, Marmosa murina, Monodelphis brevicaudata, M. domesticaand Sairadelphys tocantinensis. Furthermore, the described specimens are also part of the only fossil assemblage unequivocally referable to the late Pleistocene. Paleontological studies suggest an intimate association with dry and open environments with high abundance of water sources. Since most of the identified taxa are characteristic of open forests and gallery forests, this could represent the actual environment around the Gruta dos Moura cave. Recent studies identified sympatric occurrences between species from open and dry environments and species from humid forests that were identified among our material and are characteristic of humid regions. Therefore, these species could inhabit gallery forests and capons, or even ecotones, inside a dry and open environment. Moreover, the extinction of Sairadelphyscould also indicate that the climatic and environmental conditions changed or that the past environment was more heterogeneous than the current environment of the region.

First record of a Late Holocene fauna associated with an ephemeral fluvial sequence in La Pampa Province, Argentina. Taphonomy and paleoenvironment

Science.gov (United States)

Montalvo, Claudia I.; Fernández, Fernando J.; Bargo, M. Susana; Tomassini, Rodrigo L.; Mehl, Adriana

2017-07-01

The first Late Holocene mammal assemblage (mainly micromammals) of La Pampa Province was found in Quehué paleontological site, associated with an ephemeral fluvial sequence. Taphonomical features of the collected materials were evaluated in order to increase the knowledge of the ancient vertebrate communities of this area and to interpret the origin of the assemblages. Field data and taphonomic analysis of the specimens, suggested the recognition of three assemblages with different taphonomic histories: 1) large to medium sized mammals; 2) micromammals found inside burrows or associated with them; and 3) discrete accumulations of micromammals and other microvertebrates (amphibians, reptiles and birds). Additionally, the paleoenvironmental analysis based mainly on the record of small mammals reflected the predominance of semi-arid conditions associated with a mosaic of open shrub steppe, grasslands and xerophytic forests of Espinal, similar to the present one in the Quehué valley area. However, the presence of Lestodelphys halli in the Quehué site during the Late Holocene (∼1.2 ky BP), suggests a more heterogeneous environment and perhaps relative colder and drier than current times, which are featured by more mesic conditions and anthropic activities, mainly agriculture and livestock during the last centuries.

Insights from amphioxus into the evolution of vertebrate cartilage.

Directory of Open Access Journals (Sweden)

Daniel Meulemans

2007-08-01

Full Text Available Central to the story of vertebrate evolution is the origin of the vertebrate head, a problem difficult to approach using paleontology and comparative morphology due to a lack of unambiguous intermediate forms. Embryologically, much of the vertebrate head is derived from two ectodermal tissues, the neural crest and cranial placodes. Recent work in protochordates suggests the first chordates possessed migratory neural tube cells with some features of neural crest cells. However, it is unclear how and when these cells acquired the ability to form cellular cartilage, a cell type unique to vertebrates. It has been variously proposed that the neural crest acquired chondrogenic ability by recruiting proto-chondrogenic gene programs deployed in the neural tube, pharynx, and notochord. To test these hypotheses we examined the expression of 11 amphioxus orthologs of genes involved in neural crest chondrogenesis. Consistent with cellular cartilage as a vertebrate novelty, we find that no single amphioxus tissue co-expresses all or most of these genes. However, most are variously co-expressed in mesodermal derivatives. Our results suggest that neural crest-derived cartilage evolved by serial cooption of genes which functioned primitively in mesoderm.

Biomechanical consequences of rapid evolution in the polar bear lineage.

Directory of Open Access Journals (Sweden)

Graham J Slater

2010-11-01

Full Text Available The polar bear is the only living ursid with a fully carnivorous diet. Despite a number of well-documented craniodental adaptations for a diet of seal flesh and blubber, molecular and paleontological data indicate that this morphologically distinct species evolved less than a million years ago from the omnivorous brown bear. To better understand the evolution of this dietary specialization, we used phylogenetic tests to estimate the rate of morphological specialization in polar bears. We then used finite element analysis (FEA to compare the limits of feeding performance in the polar bear skull to that of the phylogenetically and geographically close brown bear. Results indicate that extremely rapid evolution of semi-aquatic adaptations and dietary specialization in the polar bear lineage produced a cranial morphology that is weaker than that of brown bears and less suited to processing tough omnivorous or herbivorous diets. Our results suggest that continuation of current climate trends could affect polar bears by not only eliminating their primary food source, but also through competition with northward advancing, generalized brown populations for resources that they are ill-equipped to utilize.

Visualizing Gaia Data with Science Teachers at AMNH

Science.gov (United States)

Faherty, Jacqueline K.; Desir, Deion; Coker, Kristina; Nelson, Olivia; Vasquez, Chelsea; Smithka, Iliya

2018-01-01

The American Museum of Natural History is an accredited graduate school and offers an innovative Master of Arts in Teaching (MAT) degree that leverages its unique scientific resources and long history of leadership in teacher education and professional development. The MAT program consists of 15-months of intensive mentoring, classroom experience, lab work, and professional development with AMNH scientists and educators. It is then followed by a 4 year commitment by all degree awardees to teach at an in needs New York high school. During the second summer of their first 15 months of the program, students are paired with a scientific mentor to obtain an REU like experience in Astronomy, Geology or Paleontology. During the summer of 2017 five teachers worked on incorporating a subset of the Tycho Gaia Astrometric Survey into the Partiview open source software. The result is an interactive experience where we can fly live through all of TGAS and highlight nearby clusters and associations. The tool is (1) a demonstration of the power of Partiview at visualizing a vast dataset such as Gaia, and (2) an extremely powerful instrument for teaching science through visualization.

Possible brucellosis in an early hominin skeleton from sterkfontein, South Africa.

Directory of Open Access Journals (Sweden)

Ruggero D'Anastasio

Full Text Available We report on the paleopathological analysis of the partial skeleton of the late Pliocene hominin species Australopithecus africanus Stw 431 from Sterkfontein, South Africa. A previous study noted the presence of lesions on vertebral bodies diagnosed as spondylosis deformans due to trauma. Instead, we suggest that these lesions are pathological changes due to the initial phases of an infectious disease, brucellosis. The macroscopic, microscopic and radiological appearance of the lytic lesions of the lumbar vertebrae is consistent with brucellosis. The hypothesis of brucellosis (most often associated with the consumption of animal proteins in a 2.4 to 2.8 million year old hominid has a host of important implications for human evolution. The consumption of meat has been regarded an important factor in supporting, directing or altering human evolution. Perhaps the earliest (up to 2.5 million years ago paleontological evidence for meat eating consists of cut marks on animal remains and stone tools that could have made these marks. Now with the hypothesis of brucellosis in A. africanus, we may have evidence of occasional meat eating directly linked to a fossil hominin.

Salt geologic evaluation of the impact of cryogenic fissures and halokinetic deformation processes on the integrity of the geological barrier of the salt dome Gorleben

International Nuclear Information System (INIS)

Hammer, Joerg; Fleig, Stephanie; Mingerzahn, Gerhard

2012-07-01

In several salt domes of the area close to Hannover fissures were observed that might be caused by thermally induced fissure formation due to cold periods (cryogenic fissures). Comprehensive substantial-structural analyses are performed as an example for the salt dome Bokeloh with respect to genesis and transferability to the salt dome Gorleben. Based on recent structure-geological, mineralogical-geochemical and micro-paleontological studies and thermo-mechanical modeling a solely thermally induced fissure formation due to cold periods is unlikely for the salt dome Bokeloh. There is a direct relation between the genesis of the salt dome Bokeloh, its regional tectonic site and the fissure formation. Due to the completely different genesis and another regional-tectonic situation the existence of cryogenic fissures is excluded for the salt dome Gorleben. The salt-geologic and experimental studies on the deformation of anhydrite layers in salt domes are summarized and evaluated with respect to the long-term consequences for a potential final repository for high-level heat-generating radioactive waste in the salt dome Gorleben. The studies confirm the older BGR studies that anhydrite layers do not represent hydraulic potential ling-distance liquid paths.

Biostratigraphy, facies and sequence stratigraphy of the Sarvak Formation in the Ahwaz Oil Field, North Dezful Embayment Zone

Directory of Open Access Journals (Sweden)

Mohammad Hasan Kazemzadeh

2016-08-01

Full Text Available Paleontological studies lead to recognition of 21 genera and 16 species of benthic foraminifera, 5 genera and 6 species of planktonic foraminifera and 3 genera and 3 species of oligosteginids. The vertical distribution of fauna lead to identification of 5 biozones including: Favusella washitensis Range Zone, Oligostegina Assemblage Zone, Rudist debris Zone, Nezzazata-Alveolinids Assemblage Zone, Nezzazatinella-Dicyclina Assemblage Zone. Based on the indicated biozones, the age of the Sarvak Formation is Late Albian to Early Turonian in the study area. Eleven carbonate facies belonging to four environments including tidal flat, restricted and semi-restricted lagoon, shoal and open marine are recognized. The identified facies are deposited on the homoclinal ramp setting. Based on the vertical changes of facies and recognized depositional environments, four third-order depositional sequences are represented. The transgressive systems tracts mainly comprises of open marine facies including sponge spicule, oligosteginid, echinoid and benthic foraminifera, while the highstand systems tracts mainly consists of shoal facies rich in bioclast, and restricted and semi-restricted lagoon facies rich in porcellaneous and hyaline benthic foraminifera and peloid. The maximum flooding surface represented by open marine facies including echinoid and planktonic foraminifera

Holocene alluvial stratigraphy and response to climate change in the Roaring River valley, Front Range, Colorado, USA

Science.gov (United States)

Madole, Richard F.

2012-09-01

Stratigraphic analyses and radiocarbon geochronology of alluvial deposits exposed along the Roaring River, Colorado, lead to three principal conclusions: (1) the opinion that stream channels in the higher parts of the Front Range are relics of the Pleistocene and nonalluvial under the present climate, as argued in a water-rights trial USA v. Colorado, is untenable, (2) beds of clast-supported gravel alternate in vertical succession with beds of fine-grained sediment (sand, mud, and peat) in response to centennial-scale changes in snowmelt-driven peak discharges, and (3) alluvial strata provide information about Holocene climate history that complements the history provided by cirque moraines, periglacial deposits, and paleontological data. Most alluvial strata are of late Holocene age and record, among other things, that: (1) the largest peak flows since the end of the Pleistocene occurred during the late Holocene; (2) the occurrence of a mid- to late Holocene interval (~ 2450-1630(?) cal yr BP) of warmer climate, which is not clearly identified in palynological records; and (3) the Little Ice Age climate seems to have had little impact on stream channels, except perhaps for minor (~ 1 m) incision.

Far-travelled permian chert of the North Fork terrane, Klamath mountains, California

Science.gov (United States)

Mankinen, E.A.; Irwin, W.P.; Blome, C.D.

1996-01-01

Permian chert in the North Fork terrane and correlative rocks of the Klamath Mountains province has a remanent magnetization that is prefolding and presumably primary. Paleomagnetic results indicate that the chert formed at a paleolatitude of 8.6?? ?? 2.5?? but in which hemisphere remains uncertain. This finding requires that these rocks have undergone at least 8.6?? ?? 4.4?? of northward transport relative to Permian North America since their deposition. Paleontological evidence suggests that the Permian limestone of the Eastern Klamath terrane originated thousands of kilometers distant from North America. The limestone of the North Fork terrane may have formed at a similar or even greater distance as suggested by its faunal affinity to the Eastern Klamath terrane and more westerly position. Available evidence indicates that convergence of the North Fork and composite Central Metamorphic-Eastern Klamath terranes occurred during Triassic or Early Jurassic time and that their joining together was a Middle Jurassic event. Primary and secondary magnetizations indicate that the new composite terrane containing these and other rocks of the Western Paleozoic and Triassic belt behaved as a single rigid block that has been latitudinally concordant with the North American craton since Middle Jurassic time.

Paleoclimate cycles and tectonic controls on fluvial, lacustrine, and eolian strata in upper Triassic Chinle Formation, San Juan basin

Energy Technology Data Exchange (ETDEWEB)

Dubiel, R.F. (Geological Survey, Denver, CO (USA))

1989-09-01

Sedimentologic study of the Upper Triassic Chinle Formation in the San Juan basin (SJB) indicates that Late Triassic paleoclimate and tectonic movements influenced the distribution of continental lithofacies. The Shinarump, Monitor Butte, and Petrified Forest Members in the lower part of the Chinle consist of complexly interfingered fluvial, floodplain, marsh, and lacustrine rocks; the Owl Rock and Rock Point Members in the upper part consists of lacustrine-basin and eolian sandsheet strata. Facies analysis, vertebrate and invertebrate paleontology, and paleoclimate models demonstrate that the Late Triassic was dominated by tropical monsoonal circulation, which provided abundant precipitation interspersed with seasonally dry periods. Owl Rock lacustrine strata comprise laminated limestones that reflect seasonal monsoonal precipitation and larger scale, interbedded carbonates and fine-grained clastics that represent longer term, alternating wet and dry climatic cycles. Overlying Rock Point eolian sand-sheet and dune deposits indicate persistent alternating but drier climatic cyclicity. Within the Chinle, upward succession of lacustrine, alternating lacustrine/eolian sand-sheet, and eolian sand-sheet/dune deposits reflects an overall decrease in precipitation due to the northward migration of Pangaea out of low latitudes dominated by monsoonal circulation.

Tracing the evolutionary origin of vertebrate skeletal tissues: insights from cephalochordate amphioxus.

Science.gov (United States)

Yong, Luok Wen; Yu, Jr-Kai

2016-08-01

Vertebrate mineralized skeletal tissues are widely considered as an evolutionary novelty. Despite the importance of these tissues to the adaptation and radiation of vertebrate animals, the evolutionary origin of vertebrate skeletal tissues remains largely unclear. Cephalochordates (Amphioxus) occupy a key phylogenetic position and can serve as a valuable model for studying the evolution of vertebrate skeletal tissues. Here we summarize recent advances in amphioxus developmental biology and comparative genomics that can help to elucidate the evolutionary origins of the vertebrate skeletal tissues and their underlying developmental gene regulatory networks (GRN). By making comparisons to the developmental studies in vertebrate models and recent discoveries in paleontology and genomics, it becomes evident that the collagen matrix-based connective tissues secreted by the somite-derived cells in amphioxus likely represent the rudimentary skeletal tissues in chordates. We propose that upon the foundation of this collagenous precursor, novel tissue mineralization genes that arose from gene duplications were incorporated into an ancestral mesodermal GRN that makes connective and supporting tissues, leading to the emergence of highly-mineralized skeletal tissues in early vertebrates. Copyright © 2016 Elsevier Ltd. All rights reserved.

"Replaying Life's Tape": Simulations, metaphors, and historicity in Stephen Jay Gould's view of life.

Science.gov (United States)

Sepkoski, David

2016-08-01

In a famous thought experiment, Stephen Jay Gould asked whether, if one could somehow rewind the history of life back to its initial starting point, the same results would obtain when the "tape" was run forward again. This hypothetical experiment is generally understood as a metaphor supporting Gould's philosophy of evolutionary contingency, which he developed and promoted from the late 1980s until his death in 2002. However, there was a very literal, non-metaphorical inspiration for Gould's thought experiment: since the early 1970s, Gould, along with a group of other paleontologists, was actively engaged in attempts to model and reconstruct the history of life using computer simulations and database analysis. These simulation projects not only demonstrate the impact that computers had on data analysis in paleontology, but also shed light on the close relationship between models and empirical data in data-oriented science. In a sense, I will argue, the models developed by paleontologists through simulation and quantitative analysis of the empirical fossil record in the 1970s and beyond were literal attempts to "replay life's tape" by reconstructing the history of life as data. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Fossil Calibration Database-A New Resource for Divergence Dating.

Science.gov (United States)

Ksepka, Daniel T; Parham, James F; Allman, James F; Benton, Michael J; Carrano, Matthew T; Cranston, Karen A; Donoghue, Philip C J; Head, Jason J; Hermsen, Elizabeth J; Irmis, Randall B; Joyce, Walter G; Kohli, Manpreet; Lamm, Kristin D; Leehr, Dan; Patané, Josés L; Polly, P David; Phillips, Matthew J; Smith, N Adam; Smith, Nathan D; Van Tuinen, Marcel; Ware, Jessica L; Warnock, Rachel C M

2015-09-01

Fossils provide the principal basis for temporal calibrations, which are critical to the accuracy of divergence dating analyses. Translating fossil data into minimum and maximum bounds for calibrations is the most important-often least appreciated-step of divergence dating. Properly justified calibrations require the synthesis of phylogenetic, paleontological, and geological evidence and can be difficult for nonspecialists to formulate. The dynamic nature of the fossil record (e.g., new discoveries, taxonomic revisions, updates of global or local stratigraphy) requires that calibration data be updated continually lest they become obsolete. Here, we announce the Fossil Calibration Database (http://fossilcalibrations.org), a new open-access resource providing vetted fossil calibrations to the scientific community. Calibrations accessioned into this database are based on individual fossil specimens and follow best practices for phylogenetic justification and geochronological constraint. The associated Fossil Calibration Series, a calibration-themed publication series at Palaeontologia Electronica, will serve as a key pipeline for peer-reviewed calibrations to enter the database. © The Author(s) 2015. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Accumulation conditions and exploration potential of Wufeng-Longmaxi Formations shale gas in Wuxi area, Northeastern Sichuan Basin, China

Directory of Open Access Journals (Sweden)

Wei Wu

2017-12-01

Full Text Available Wufeng-Longmaxi Formations shale gas is a new exploration field in Wuxi area, Sichuan Basin, China. Some geological parameters related to shale gas evaluation of the new exploration wells in Wuxi area have been studied, including shale reservoir, gas-bearing, geochemical and paleontological characteristics. The study suggests that the original shale gas generation conditions of the area were good, but later this area went through serious and multi-phase tectonic damage. The major evidences include that: the δ13C2 value of shale gas is obviously higher than that in areas with the same maturity, indicating the shale gas is mainly late kerogen cracking gas and high hydrocarbon expulsion efficiency; the porosity of shale in Wuxi area is very low because of strong tectonic movements and lack of retained oil in the shale; some shale cores near faults even show very weak metamorphic characteristics with intense cleavage, and the epidermis of graptolite fossils was pyrolyzed. The comprehensive study shows shale gas in Wuxi area has prospective resources, but the possibility to get scale commercial production in recent time is very low.

Vegetation structure and species diversity of Wadi Turbah Zahran, Albaha area, southwestern Saudi Arabia

Directory of Open Access Journals (Sweden)

Sami Asir Al-Robai

2017-06-01

Full Text Available The aim of this work was to study the vegetation structure of Wadi Turbah Zahran, Albaha area, Saudi Arabia and some biodiversity indices. Paleontological Statistics (PAST Software Package was used for data analysis. A total of 266 species (201 genera, 71 families were identified and most of the species were herbs (87%. Therophytes (32.7% and Chamaephytes (30.45% were the most prominent groups. Asteraceae family was represented by the highest number of species (15.4% followed by Poaceae (9.4%. Thirty-one families (43.7% were represented by a single genus and species. Thirty-four species (12.8% were common to all sites. The genus Solanum was the most speciose followed by Rumex. Most of the calculated indices showed variations among the sites. Shannon (3.71–4.06, Menhenick (2.271–4.746 and Chao-1 (106–319.6 diversity indices markedly varied among the sites while Simpson values (0.96–0.97 were almost the same. Berger-Parker values revealed the dominance of Hyparrhenia hirta in four sites. Beta diversity values indicated high diversity between site 1 and 4 and less diversity between site 1 and 6.

Classification of radiolarian images with hand-crafted and deep features

Science.gov (United States)

Keçeli, Ali Seydi; Kaya, Aydın; Keçeli, Seda Uzunçimen

2017-12-01

Radiolarians are planktonic protozoa and are important biostratigraphic and paleoenvironmental indicators for paleogeographic reconstructions. Radiolarian paleontology still remains as a low cost and the one of the most convenient way to obtain dating of deep ocean sediments. Traditional methods for identifying radiolarians are time-consuming and cannot scale to the granularity or scope necessary for large-scale studies. Automated image classification will allow making these analyses promptly. In this study, a method for automatic radiolarian image classification is proposed on Scanning Electron Microscope (SEM) images of radiolarians to ease species identification of fossilized radiolarians. The proposed method uses both hand-crafted features like invariant moments, wavelet moments, Gabor features, basic morphological features and deep features obtained from a pre-trained Convolutional Neural Network (CNN). Feature selection is applied over deep features to reduce high dimensionality. Classification outcomes are analyzed to compare hand-crafted features, deep features, and their combinations. Results show that the deep features obtained from a pre-trained CNN are more discriminative comparing to hand-crafted ones. Additionally, feature selection utilizes to the computational cost of classification algorithms and have no negative effect on classification accuracy.

The dawn of chelonian research: turtles between comparative anatomy and embryology in the 19th century.

Science.gov (United States)

MacCord, Kate; Caniglia, Guido; Moustakas-Verho, Jacqueline E; Burke, Ann C

2015-05-01

Many evo-devo studies of the turtle's shell draw hypotheses and support from historical sources. The groundbreaking works of Cuvier, Geoffroy St. Hilaire, Carus, Rathke, Owen, and others are being revived in modern research, and their centuries-old understanding of the turtle's shell reconsidered. In the works of these eminent biologists of the 19th century, comparative anatomy and embryology of turtle morphology set the stage for future studies in developmental biology, histology, and paleontology. Given the impact that these works still make on modern research, it is important to develop a thorough appreciation of previous authors, regarding how they arrived at their conclusions (i.e., what counted as evidence?), whether there was debate amongst these authors about shell development (i.e., what counted as an adequate explanation?), and even why these men, some of the most powerful and influential thinkers and anatomists of their day, were concerned with turtles. By tracing and exposing the context and content of turtle shell studies in history, our aim is to inform modern debates about the evolution and development of the turtle's shell. © 2014 Wiley Periodicals, Inc.

Visualizing Complex Environments in the Geo- and BioSciences

Science.gov (United States)

Prabhu, A.; Fox, P. A.; Zhong, H.; Eleish, A.; Ma, X.; Zednik, S.; Morrison, S. M.; Moore, E. K.; Muscente, D.; Meyer, M.; Hazen, R. M.

2017-12-01

Earth's living and non-living components have co-evolved for 4 billion years through numerous positive and negative feedbacks. Earth and life scientists have amassed vast amounts of data in diverse fields related to planetary evolution through deep time-mineralogy and petrology, paleobiology and paleontology, paleotectonics and paleomagnetism, geochemistry and geochrononology, genomics and proteomics, and more. Integrating the data from these complimentary disciplines is very useful in gaining an understanding of the evolution of our planet's environment. The integrated data however, represent many extremely complex environments. In order to gain insights and make discoveries using this data, it is important for us to model and visualize these complex environments. As part of work in understanding the "Co-Evolution of Geo and Biospheres using Data Driven Methodologies," we have developed several visualizations to help represent the information stored in the datasets from complimentary disciplines. These visualizations include 2D and 3D force directed Networks, Chord Diagrams, 3D Klee Diagrams. Evolving Network Diagrams, Skyline Diagrams and Tree Diagrams. Combining these visualizations with the results of machine learning and data analysis methods leads to a powerful way to discover patterns and relationships about the Earth's past and today's changing environment.

THALAMID SPONGES FROM THE UPPER TRIASSIC (NORIAN-RHAETIAN NAYBAND FORMATION NEAR WALI-ABAD, SE ABADEH, CENTRAL IRAN(CONTRIBUTION TO TRIASSIC PALEONTOLOGY OF IRAN 4

Directory of Open Access Journals (Sweden)

BABA SENOWBARI-DARYAN

1999-03-01

Full Text Available An association of thalamid sponges including Amblysiphonella, Nevadathalamia, Stylothalamia, and Neoguadalupia, with the hexactinellid Casearia is described from the Upper Triassic (Norian-Rhaetian Nayband Formation of Hambast-Mts. near the small town of Wali-Abad (Abadeh region, central Iran. These Norian-Rhaetian (Neoguadalupia, Amblysiphonella, Nevadathalamia and Liassic (Stylothalamia columnaris Le Maitre thalamid sponge assemblages are exceptional associations, not previously reported from Iran nor from other localities in the world. The microfacies and organism associations in the sponge-bearing carbonates is discussed. Differences of macro- and microfaunal composition, as well as flora, support the recognition of Kristan-Tollmann et al. to classify the Nayband Formation in the Abadeh region as of a distinct unit, termed the "Wali-Abad-Faziesregion". Following thalamid sponge species are described as new: Nevadathalamia waliabadensis n. sp. and Stylothalamia hambastensis n. sp. 

Dartmouth College Earth Sciences Mobile Field Program

Science.gov (United States)

Meyer, E. E.; Osterberg, E. C.; Dade, W. B.; Sonder, L. J.; Renshaw, C. E.; Kelly, M. A.; Hawley, R. L.; Chipman, J. W.; Mikucki, J.; Posmentier, E. S.; Moore, J. R.

2011-12-01

For the last 50 years the Department of Earth Sciences at Dartmouth College has offered a term-long, undergraduate field program, informally called "the Stretch". A student typically enrolls during fall quarter of his or her junior year soon after choosing a major or minor. The program thus provides valuable field context for courses that a student will take during the remainder of his or her undergraduate career. Unlike many traditional field camps that focus on one particular region, the Stretch is a mobile program that currently travels through Western North America, from the Canadian Rockies to the Grand Canyon. The program spans two and a half months, during which time undergraduates, graduate TAs, and faculty live, work, and learn collaboratively. Dartmouth College faculty members sequentially teach individual 1- to 2-week segments that focus on their interests and expertise; currently, there are a total of eight segments led by eleven faculty members. Consequently, topics are diverse and include economic geology, geobiology, geomorphology, glaciology, glacial geology, geophysics, hydrogeology, paleontology, stratigraphy, structure and tectonics, and volcanology. The field localities are equally varied, including the alpine glaciers of western Alberta, the national parks of Montana, Wyoming and Utah, the eastern Sierra Nevada, the southern Great Basin, and highlight such classic geological field locales as Sheep Mountain in Wyoming's Bighorn Basin, Death Valley, and the Grand Canyon. Overall, the program aims to: 1) give students a broad perspective on the timing and nature of the processes that resulted in the landscape and underlying geology of western North America; and 2) introduce students to a wide variety of geological environments, field techniques, and research equipment. Students emerge from the program with wide-ranging exposure to active research questions as well as a working knowledge of core field skills in the earth sciences. Stretch students

Application of Reflectance Transformation Imaging Technique to Improve Automated Edge Detection in a Fossilized Oyster Reef

Science.gov (United States)

Djuricic, Ana; Puttonen, Eetu; Harzhauser, Mathias; Dorninger, Peter; Székely, Balázs; Mandic, Oleg; Nothegger, Clemens; Molnár, Gábor; Pfeifer, Norbert

2016-04-01

The world's largest fossilized oyster reef is located in Stetten, Lower Austria excavated during field campaigns of the Natural History Museum Vienna between 2005 and 2008. It is studied in paleontology to learn about change in climate from past events. In order to support this study, a laser scanning and photogrammetric campaign was organized in 2014 for 3D documentation of the large and complex site. The 3D point clouds and high resolution images from this field campaign are visualized by photogrammetric methods in form of digital surface models (DSM, 1 mm resolution) and orthophoto (0.5 mm resolution) to help paleontological interpretation of data. Due to size of the reef, automated analysis techniques are needed to interpret all digital data obtained from the field. One of the key components in successful automation is detection of oyster shell edges. We have tested Reflectance Transformation Imaging (RTI) to visualize the reef data sets for end-users through a cultural heritage viewing interface (RTIViewer). The implementation includes a Lambert shading method to visualize DSMs derived from terrestrial laser scanning using scientific software OPALS. In contrast to shaded RTI no devices consisting of a hardware system with LED lights, or a body to rotate the light source around the object are needed. The gray value for a given shaded pixel is related to the angle between light source and the normal at that position. Brighter values correspond to the slope surfaces facing the light source. Increasing of zenith angle results in internal shading all over the reef surface. In total, oyster reef surface contains 81 DSMs with 3 m x 2 m each. Their surface was illuminated by moving the virtual sun every 30 degrees (12 azimuth angles from 20-350) and every 20 degrees (4 zenith angles from 20-80). This technique provides paleontologists an interactive approach to virtually inspect the oyster reef, and to interpret the shell surface by changing the light source direction

Marine ecology conditions at Weda Bay, North Maluku based on statistical analysis on distribution of recent foraminifera

Directory of Open Access Journals (Sweden)

Kurniasih Anis

2017-01-01

Full Text Available Analysis of foraminifera in geology,usually being used to find the age of rocks/ sediments and depositional environment. In this study, recent foraminifera was used not only to determinethe sedimentary environment,but also to estimate the ecological condition of the water through a statistical approach.Analysis was performed quantitatively in 10 surface seabed sediment samples in Weda Bay North Maluku. The analysis includes dominance (Sympson Index, diversity and evenness (Shannon Index, and the ratio of planktonic -benthic. The results were shown in the plotting diagram of M-R-T (Miliolid-Rotalid-Textularid to determine the depositional environment. Quantitative analysis was performed using Past software (paleontological version Statistic 1:29.The analysis result showed there was no domination of certain taxon with a moderate degree of evenness and stable communities and considerably a moderate diversity. The results of this analysis indicated that research area had a stable water conditions with the optimum level of carbonate content, oxygen supply, salinity, and temperature. The ratio of planktonic and benthic indicate the relative depth, which was deeper the water increased the percentage of planktonic foraminifera. Based on M-R-T diagram showed the distribution of sediment deposited on exposed carbonate (carbonate platform environment with normal saline.

Promise and pitfalls for characterizing and correlating the zeolitically altered tephra of the Pleistocene Peninj Group, Tanzania

Science.gov (United States)

McHenry, Lindsay J.; Luque, Luis; Gómez, José Ángel; Diez-Martín, Fernando

2011-05-01

The Pleistocene Humbu and Moinik formations of the Peninj Group in northern Tanzania preserve an important archaeological and paleontological record, in addition to a record of local volcanism in the form of tephra and lavas. Samples of the major Humbu and Moinik formations' basaltic and trachytic tephra were collected and characterized using phenocryst composition and both primary and authigenic mineral assemblage, since the volcanic glass was completely altered to zeolite. Some tephra are distinguishable solely using phenocrysts, but some are too similar in mineral composition or too poor in phenocrysts to definitively "fingerprint" without glass. Titanomagnetite phenocrysts were mostly altered; characterization was thus limited to feldspar, augite, and hornblende compositions for most tephra. Phenocryst compositions were compared to Olduvai tephra compositions to see if any regional tephra could be identified that could help correlate the sites. Augite or hornblende composition rules out potential correlations of Olduvai Bed I Tuff IF and the Bed II Bird Print Tuff or Tuff IID to otherwise similar Peninj Group tephra. Despite their overlap in age and locations at less than ~ 80 km from the Ngorongoro Volcanic Highlands, Peninj and Olduvai have different tephra records, which limits the possibilities for establishing a regional tephrostratigraphic framework.

Mitochondrial genomes suggest rapid evolution of dwarf California Channel Islands foxes (Urocyon littoralis).

Science.gov (United States)

Hofman, Courtney A; Rick, Torben C; Hawkins, Melissa T R; Funk, W Chris; Ralls, Katherine; Boser, Christina L; Collins, Paul W; Coonan, Tim; King, Julie L; Morrison, Scott A; Newsome, Seth D; Sillett, T Scott; Fleischer, Robert C; Maldonado, Jesus E

2015-01-01

Island endemics are typically differentiated from their mainland progenitors in behavior, morphology, and genetics, often resulting from long-term evolutionary change. To examine mechanisms for the origins of island endemism, we present a phylogeographic analysis of whole mitochondrial genomes from the endangered island fox (Urocyon littoralis), endemic to California's Channel Islands, and mainland gray foxes (U. cinereoargenteus). Previous genetic studies suggested that foxes first appeared on the islands >16,000 years ago, before human arrival (~13,000 cal BP), while archaeological and paleontological data supported a colonization >7000 cal BP. Our results are consistent with initial fox colonization of the northern islands probably by rafting or human introduction ~9200-7100 years ago, followed quickly by human translocation of foxes from the northern to southern Channel Islands. Mitogenomes indicate that island foxes are monophyletic and most closely related to gray foxes from northern California that likely experienced a Holocene climate-induced range shift. Our data document rapid morphological evolution of island foxes (in ~2000 years or less). Despite evidence for bottlenecks, island foxes have generated and maintained multiple mitochondrial haplotypes. This study highlights the intertwined evolutionary history of island foxes and humans, and illustrates a new approach for investigating the evolutionary histories of other island endemics.

Ripensare Darwin? Di ex‐aptations e neotenie. E di Topolino, Pippo e simpatiche salamandre messicane

Directory of Open Access Journals (Sweden)

AMODIO, PAOLO

2016-12-01

Full Text Available Rethinking Darwin? About Ex‐aptations and Neotenies. Concerning Mickey Mouse, Goofy and likeable mexican Salamanders The theory of evolution by natural selection of Charles Darwin, whose first general exposure dates back to 1859, with the publication of the Origin of Species, is still a matter of intense debate among natural sciences’ scholars and philosophers. After the merger of Darwinian evolutionary research program with the theory of heredity of Gregor Mendel, the mathematical form of population genetics and the analysis of paleontological data (Modern Synthesis and the the important contributions of post-Darwinian authors such as S.J. Gould and N. Eldredge we are entering a new era of great discoveries and news. On the one hand, new data from genetics and paleoanthropology, on the other hand the impetuous development of some fields of applied science such as nanobiotechnology, genetic engineering and synthetic biology put us into the need and the urgency to underline, once again, the relevance and the extraordinary heuristic power of Darwinian research program, an even greater urgency since some authors have announced that we would be at a time to access a post-Darwinian and post-evolutionary era in which man as we actually know it is about to disappear.

High-resolution x-ray computed tomography to understand ruminant phylogeny

Science.gov (United States)

Costeur, Loic; Schulz, Georg; Müller, Bert

2014-09-01

High-resolution X-ray computed tomography has become a vital technique to study fossils down to the true micrometer level. Paleontological research requires the non-destructive analysis of internal structures of fossil specimens. We show how X-ray computed tomography enables us to visualize the inner ear of extinct and extant ruminants without skull destruction. The inner ear, a sensory organ for hearing and balance has a rather complex three-dimensional morphology and thus provides relevant phylogenetical information what has been to date essentially shown in primates. We made visible the inner ears of a set of living and fossil ruminants using the phoenix x-ray nanotom®m (GE Sensing and Inspection Technologies GmbH). Because of the high absorbing objects a tungsten target was used and the experiments were performed with maximum accelerating voltage of 180 kV and a beam current of 30 μA. Possible stem ruminants of the living families are known in the fossil record but extreme morphological convergences in external structures such as teeth is a strong limitation to our understanding of the evolutionary history of this economically important group of animals. We thus investigate the inner ear to assess its phylogenetical potential for ruminants and our first results show strong family-level morphological differences.

A molecular mechanism for the origin of a key evolutionary innovation, the bird beak and palate, revealed by an integrative approach to major transitions in vertebrate history.

Science.gov (United States)

Bhullar, Bhart-Anjan S; Morris, Zachary S; Sefton, Elizabeth M; Tok, Atalay; Tokita, Masayoshi; Namkoong, Bumjin; Camacho, Jasmin; Burnham, David A; Abzhanov, Arhat

2015-07-01

The avian beak is a key evolutionary innovation whose flexibility has permitted birds to diversify into a range of disparate ecological niches. We approached the problem of the mechanism behind this innovation using an approach bridging paleontology, comparative anatomy, and experimental developmental biology. First, we used fossil and extant data to show the beak is distinctive in consisting of fused premaxillae that are geometrically distinct from those of ancestral archosaurs. To elucidate underlying developmental mechanisms, we examined candidate gene expression domains in the embryonic face: the earlier frontonasal ectodermal zone (FEZ) and the later midfacial WNT-responsive region, in birds and several reptiles. This permitted the identification of an autapomorphic median gene expression region in Aves. To test the mechanism, we used inhibitors of both pathways to replicate in chicken the ancestral amniote expression. Altering the FEZ altered later WNT responsiveness to the ancestral pattern. Skeletal phenotypes from both types of experiments had premaxillae that clustered geometrically with ancestral fossil forms instead of beaked birds. The palatal region was also altered to a more ancestral phenotype. This is consistent with the fossil record and with the tight functional association of avian premaxillae and palate in forming a kinetic beak. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

Forelimbs of Tyrannosaurus Rex: A pathetic vestigial organ or an integral part of a fearsome predator?

Science.gov (United States)

Lee, Scott A.; Thomas, Joshua D.

2014-12-01

In this paper, we examine a first-year torque and angular acceleration problem to address a possible use of the forelimbs of Tyrannosaurus rex. A 1/40th-scale model (see Fig. 1) is brought to the classroom to introduce the students to the quandary: given that the forelimbs of T. rex were too short to reach its mouth, what function did the forelimbs serve? This issue crosses several scientific disciplines including paleontology, ecology, and physics, making it a great starting point for thinking "outside the box." Noted paleontologist Kenneth Carpenter has suggested that the forelimbs of T. rex were an integral part of its predatory behavior. Given the large teeth of T. rex, it is assumed that they killed with their teeth. Lipkin and Carpenter1 have suggested that the forelimbs were used to hold a struggling victim (which had not been dispatched with the first bite) while the final, lethal bite was applied. If that is the case, then the forelimbs must be capable of large angular accelerations α in order to grab the animal attempting to escape. The concepts of the typical first-year physics course are sufficient to test this hypothesis by solving α =τ /I . Naturally, students love solving any problem related to Tyrannosaurus rex!

Ancient DNA analysis of the oldest canid species from the Siberian Arctic and genetic contribution to the domestic dog.

Directory of Open Access Journals (Sweden)

Esther J Lee

Full Text Available Modern Arctic Siberia provides a wealth of resources for archaeological, geological, and paleontological research to investigate the population dynamics of faunal communities from the Pleistocene, particularly as the faunal material coming from permafrost has proven suitable for genetic studies. In order to examine the history of the Canid species in the Siberian Arctic, we carried out genetic analysis of fourteen canid remains from various sites, including the well-documented Upper Paleolithic Yana RHS and Early Holocene Zhokhov Island sites. Estimated age of samples range from as recent as 1,700 years before present (YBP to at least 360,000 YBP for the remains of the extinct wolf, Canis cf. variabilis. In order to examine the genetic affinities of ancient Siberian canids species to the domestic dog and modern wolves, we obtained mitochondrial DNA control region sequences and compared them to published ancient and modern canid sequences. The older canid specimens illustrate affinities with pre-domestic dog/wolf lineages while others appear in the major phylogenetic clades of domestic dogs. Our results suggest a European origin of domestic dog may not be conclusive and illustrates an emerging complexity of genetic contribution of regional wolf breeds to the modern Canis gene pool.

Correlations of some Neoproterozoic carbonate-dominated successions in South America based on high-resolution chemostratigraphy

Directory of Open Access Journals (Sweden)

Alcides Nobrega Sial

Full Text Available ABSTRACT: This report reviews and incorporates new elemental and isotope chemostratigraphic data for correlation of Neoproterozoic carbonate-dominated successions in South America (Argentina, Bolivia, Brazil, Paraguay and Uruguay. These thick mixed carbonate/siliciclastic successions were largely deposited in epicontinental basins or accumulated on passive margins on the edges of cratons (e.g. São Francisco, Amazonia, Rio Apa Block, Pampia and Río de la Plata paleocontinents during extensional events related to the rifting of the Rodinia Supercontinent. From the stratigraphic point of view, these successions occur as three mega-sequences: glaciogenic, marine carbonate platform (above glaciomarine diamictites or rift successions, and dominantly continental to transitional siliciclastics. In the orogenic belts surrounding cratons, carbonate-dominated successions with important volcanoclastic/siliciclastic contribution have been, in most cases, strongly deformed. The precise ages of these successions remain a matter of debate, but recently new paleontological and geochronological data have considerably constrained depositional intervals. Here, we report high-resolution C, O, Sr, and S isotope trends measured in well-preserved sample sets and mainly use Sr and C isotopes in concert with lithostratigraphic/biostratigraphic observations to provide detailed correlations of these successions. The establishing of a high-level and definite chemostratigraphic correlation between Neoproterozoic basins in South America is the main goal of this work.

ARCTOS: a relational database relating specimens, specimen-based science, and archival documentation

Science.gov (United States)

Jarrell, Gordon H.; Ramotnik, Cindy A.; McDonald, D.L.

2010-01-01

Data are preserved when they are perpetually discoverable, but even in the Information Age, discovery of legacy data appropriate to particular investigations is uncertain. Secure Internet storage is necessary but insufficient. Data can be discovered only when they are adequately described, and visibility increases markedly if the data are related to other data that are receiving usage. Such relationships can be built within (1) the framework of a relational database, or (1) they can be built among separate resources, within the framework of the Internet. Evolving primarily around biological collections, Arctos is a database that does both of these tasks. It includes data structures for a diversity of specimen attributes, essentially all collection-management tasks, plus literature citations, project descriptions, etc. As a centralized collaboration of several university museums, Arctos is an ideal environment for capitalizing on the many relationships that often exist between items in separate collections. Arctos is related to NIH’s DNA-sequence repository (GenBank) with record-to-record reciprocal linkages, and it serves data to several discipline-specific web portals, including the Global Biodiversity Information Network (GBIF). The University of Alaska Museum’s paleontological collection is Arctos’s recent extension beyond the constraints of neontology. With about 1.3 million cataloged items, additional collections are being added each year.

Los Lamini (Cetartiodactyla: Camelidae extintos del yacimiento de Pilauco (Norpatagonia chilena: aspectos taxonómicos y tafonómicos preliminares

Directory of Open Access Journals (Sweden)

Labarca Encina, Rafael

2013-12-01

Full Text Available We present a preliminary description and taxonomic assignment of the Lamini fossil remains recovered from the paleontological site of Pilauco (late Pleistocene in southern Chile. Based on metric variables the fossils are temporarily asigned to cf. Hemiauchenia paradoxa Gervais & Ameghino 1880, waiting for new and more diagnostic remains. We present and discuss some taphonomic processes occurring within the site, starting from the study of the marks observed in the surface of the fossils, wich are consistent with the bog environment with occasional fluvial flooding described for the site.Se presenta la descripción y asignación taxonómica preliminar de los restos de Lamini recuperados en el sitio paleontológico de Pilauco (Pleistoceno tardío ubicado en el sur de Chile. Sobre la base de variables métricas los materiales son provisoriamente incluidos en cf. Hemiauchenia paradoxa Gervais & Ameghino 1880 a la espera de materiales más diagnósticos. Se discuten algunos procesos tafonómicos ocurridos al interior del yacimiento a partir del estudio de las marcas registradas en la superficie de los fósiles, las que son concordantes con el ambiente palustre con inundaciones esporádicas fluviales descrito para el sitio.

A unified anatomy ontology of the vertebrate skeletal system.

Directory of Open Access Journals (Sweden)

Wasila M Dahdul

Full Text Available The skeleton is of fundamental importance in research in comparative vertebrate morphology, paleontology, biomechanics, developmental biology, and systematics. Motivated by research questions that require computational access to and comparative reasoning across the diverse skeletal phenotypes of vertebrates, we developed a module of anatomical concepts for the skeletal system, the Vertebrate Skeletal Anatomy Ontology (VSAO, to accommodate and unify the existing skeletal terminologies for the species-specific (mouse, the frog Xenopus, zebrafish and multispecies (teleost, amphibian vertebrate anatomy ontologies. Previous differences between these terminologies prevented even simple queries across databases pertaining to vertebrate morphology. This module of upper-level and specific skeletal terms currently includes 223 defined terms and 179 synonyms that integrate skeletal cells, tissues, biological processes, organs (skeletal elements such as bones and cartilages, and subdivisions of the skeletal system. The VSAO is designed to integrate with other ontologies, including the Common Anatomy Reference Ontology (CARO, Gene Ontology (GO, Uberon, and Cell Ontology (CL, and it is freely available to the community to be updated with additional terms required for research. Its structure accommodates anatomical variation among vertebrate species in development, structure, and composition. Annotation of diverse vertebrate phenotypes with this ontology will enable novel inquiries across the full spectrum of phenotypic diversity.

Fossils, molecules, divergence times, and the origin of lissamphibians.

Science.gov (United States)

Marjanović, David; Laurin, Michel

2007-06-01

A review of the paleontological literature shows that the early dates of appearance of Lissamphibia recently inferred from molecular data do not favor an origin of extant amphibians from temnospondyls, contrary to recent claims. A supertree is assembled using new Mesquite modules that allow extinct taxa to be incorporated into a time-calibrated phylogeny with a user-defined geological time scale. The supertree incorporates 223 extinct species of lissamphibians and has a highly significant stratigraphic fit. Some divergences can even be dated with sufficient precision to serve as calibration points in molecular divergence date analyses. Fourteen combinations of minimal branch length settings and 10 random resolutions for each polytomy give much more recent minimal origination times of lissamphibian taxa than recent studies based on a phylogenetic analyses of molecular sequences. Attempts to replicate recent molecular date estimates show that these estimates depend strongly on the choice of calibration points, on the dating method, and on the chosen model of evolution; for instance, the estimate for the date of the origin of Lissamphibia can lie between 351 and 266 Mya. This range of values is generally compatible with our time-calibrated supertree and indicates that there is no unbridgeable gap between dates obtained using the fossil record and those using molecular evidence, contrary to previous suggestions.

Geologic constraints and speleogenesis of Cova des Pas de Vallgornera, a complex coastal cave from Mallorca Island (Western Mediterranean

Directory of Open Access Journals (Sweden)

Joaquín Ginés

2014-05-01

Full Text Available The flat areas of eastern and southern Mallorca host a remarkable coastal karst, where Cova des Pas de Vallgornera stands out due to its length (more than 74 km and its special morphological suite. The pattern of the cave is quite heterogeneous showing sharp differences produced by the architecture of the Upper Miocene reef: spongework mazes and collapse chambers dominate in the reef front facies, whereas joint-guided conduits are the rule in the back reef carbonates. Regarding the speleogenesis of the system, a complex situation is envisaged involving three main agents: coastal mixing dissolution, drainage of meteoric diffuse recharge, and hypogene basal recharge related to local geothermal phenomena. The cave system is disposed in two main tiers of passages, of which geomorphologic interpretations are derived from their elevation data. The evolutionary trends as well as the chronology of the different cave sections are difficult to establish owing to the frequent shifting of the coastal base level during the Plio-Quaternary. In this respect, the genesis and evolution of the cave were fully controlled by sea-level fluctuations in the Western Mediterranean basin, with the main phases of cave formation, based on vertebrate paleontological data, going back to mid-Pliocene times.

Was Frozen Mammoth or Giant Ground Sloth Served for Dinner at The Explorers Club?

Directory of Open Access Journals (Sweden)

Jessica R Glass

Full Text Available Accounts of woolly mammoths (Mammuthus primigenius preserved so well in ice that their meat is still edible have a long history of intriguing the public and influencing paleontological thought on Quaternary extinctions and climate, with some scientists resorting to catastrophism to explain the instantaneous freezing necessary to preserve edible meat. Famously, members of The Explorers Club purportedly dined on frozen mammoth from Alaska, USA, in 1951. This event, well received by the press and general public, became an enduring legend for the Club and popularized the notorious annual tradition of serving rare and exotic food at Club dinners that continues to this day. The Yale Peabody Museum holds a sample of meat preserved from the 1951 meal, interestingly labeled as a South American giant ground sloth (Megatherium, not mammoth. We sequenced a fragment of the mitochondrial cytochrome-b gene and studied archival material to verify its identity, which if genuine, would extend the range of Megatherium over 600% and alter our views on ground sloth evolution. Our results indicate that the meat was not mammoth or Megatherium but green sea turtle (Chelonia mydas. The prehistoric dinner was likely an elaborate publicity stunt. Our study emphasizes the value of museums collecting and curating voucher specimens, particularly those used for evidence of extraordinary claims.

Fish faunas from the Late Jurassic (Tithonian) Vaca Muerta Formation of Argentina: One of the most important Jurassic marine ichthyofaunas of Gondwana

Science.gov (United States)

Gouiric-Cavalli, Soledad; Cione, Alberto Luis

2015-11-01

The marine deposits of the Vaca Muerta Formation (Tithonian-Berriasian) houses one of the most diverse Late Jurassic ichthyofaunas of Gondwana. However, most of the specimens remain undescribed. Jurassic fishes have been recovered from several localities at Neuquén Province (i.e., Picún Leufú, Plaza Huincul, Cerro Lotena, Portada Las Lajas, Los Catutos, and Arroyo Covunco) but also from Mendoza Province (i.e., La Valenciana, Los Molles, and Arroyo del Cajón Grande). Presently, the fish fauna of Los Catutos, near Zapala city (Neuquén Province), has yielded the highest number of specimens, which are taxonomically and morphologically diverse. At Los Catutos locality, the Vaca Muerta Formation is represented by the Los Catutos Member, which is considered the only lithographic limestones known in the Southern Hemisphere. Here, we review the Tithonian fish faunas from the Vaca Muerta Formation. During Late Jurassic times, the actual Argentinian territory could have been a morphological diversification center, at least for some actinopterygian groups. The apparently lower species diversity recorded in marine Jurassic ichthyofaunas of Argentina (and some Gondwanan countries) in comparison with Chilean and European fish faunas could be related to the fish paleontological research history in Gondwana and the low number of detailed studies of most of specimens recorded.

The last dinosaurs of Brazil: The Bauru Group and its implications for the end-Cretaceous mass extinction

Directory of Open Access Journals (Sweden)

STEPHEN L. BRUSATTE

Full Text Available ABSTRACT The non-avian dinosaurs died out at the end of the Cretaceous, ~66 million years ago, after an asteroid impact. The prevailing hypothesis is that the effects of the impact suddenly killed the dinosaurs, but the poor fossil record of latest Cretaceous (Campanian-Maastrichtian dinosaurs from outside Laurasia (and even more particularly, North America makes it difficult to test specific extinction scenarios. Over the past few decades, a wealth of new discoveries from the Bauru Group of Brazil has revealed a unique window into the evolution of terminal Cretaceous dinosaurs from the southern continents. We review this record and demonstrate that there was a diversity of dinosaurs, of varying body sizes, diets, and ecological roles, that survived to the very end of the Cretaceous (Maastrichtian: 72-66 million years ago in Brazil, including a core fauna of titanosaurian sauropods and abelisaurid and carcharodontosaurid theropods, along with a variety of small-to-mid-sized theropods. We argue that this pattern best fits the hypothesis that southern dinosaurs, like their northern counterparts, were still diversifying and occupying prominent roles in their ecosystems before the asteroid suddenly caused their extinction. However, this hypothesis remains to be tested with more refined paleontological and geochronological data, and we give suggestions for future work.

Variation, variability, and the origin of the avian endocranium: insights from the anatomy of Alioramus altai (Theropoda: Tyrannosauroidea.

Directory of Open Access Journals (Sweden)

Gabe S Bever

Full Text Available The internal braincase anatomy of the holotype of Alioramus altai, a relatively small-bodied tyrannosauroid from the Late Cretaceous of Mongolia, was studied using high-resolution computed tomography. A number of derived characters strengthen the diagnosis of this taxon as both a tyrannosauroid and a unique, new species (e.g., endocranial position of the gasserian ganglion, internal ramification of the facial nerve. Also present are features intermediate between the basal theropod and avialan conditions that optimize as the ancestral condition for Coelurosauria--a diverse group of derived theropods that includes modern birds. The expression of several primitive theropod features as derived character states within Tyrannosauroidea establishes previously unrecognized evolutionary complexity and morphological plasticity at the base of Coelurosauria. It also demonstrates the critical role heterochrony may have played in driving patterns of endocranial variability within the group and potentially reveals stages in the evolution of neuroanatomical development that could not be inferred based solely on developmental observations of the major archosaurian crown clades. We discuss the integration of paleontology with variability studies, especially as applied to the nature of morphological transformations along the phylogenetically long branches that tend to separate the crown clades of major vertebrate groups.

The last dinosaurs of Brazil: The Bauru Group and its implications for the end-Cretaceous mass extinction.

Science.gov (United States)

Brusatte, Stephen L; Candeiro, Carlos R A; Simbras, Felipe M

2017-01-01

The non-avian dinosaurs died out at the end of the Cretaceous, ~66 million years ago, after an asteroid impact. The prevailing hypothesis is that the effects of the impact suddenly killed the dinosaurs, but the poor fossil record of latest Cretaceous (Campanian-Maastrichtian) dinosaurs from outside Laurasia (and even more particularly, North America) makes it difficult to test specific extinction scenarios. Over the past few decades, a wealth of new discoveries from the Bauru Group of Brazil has revealed a unique window into the evolution of terminal Cretaceous dinosaurs from the southern continents. We review this record and demonstrate that there was a diversity of dinosaurs, of varying body sizes, diets, and ecological roles, that survived to the very end of the Cretaceous (Maastrichtian: 72-66 million years ago) in Brazil, including a core fauna of titanosaurian sauropods and abelisaurid and carcharodontosaurid theropods, along with a variety of small-to-mid-sized theropods. We argue that this pattern best fits the hypothesis that southern dinosaurs, like their northern counterparts, were still diversifying and occupying prominent roles in their ecosystems before the asteroid suddenly caused their extinction. However, this hypothesis remains to be tested with more refined paleontological and geochronological data, and we give suggestions for future work.

The Intertropical Convergence Zone over the Middle East and North Africa: Detection and Trends

KAUST Repository

Scott, Anna A.

2013-01-01

This thesis provides an overview of identifying the Intertropical Convergence Zone (ITCZ) in the Middle East and North Africa (MENA) region. The ITCZ is a zone of wind convergence around the equator that coincides with an area of intense precipitation that is commonly termed a tropical rainbelt. In Africa, these two concepts are frequently confounded. This work studies the correlation between precipitation and commonly used ITCZ indicators. A further attempt is made to detect movement in the African ITCZ, based on earlier paleontological studies showing historical changes in precipitation. Zonally averaged wind convergence is found to be the most reliable indicator of the African ITCZ, one having a low correlation with zonally averaged precipitation. Precipitation is found only to be a reliable indicator for the African ITCZ in zones near the wind convergence, which reaches as far north as 20_N in the summer. No secular change in location of the African ITCZ is found for the time of available data. Finally, historical data shows that any increase in precipitation in the Sahel, a region where precipitation is driven by the ITCZ, is mildly negatively correlated with precipitation in the rainbelt area, suggesting that shifts in the ITCZ result in a widening of the precipitation profile as well as a shift of the entire zone.

Morphometric and genetic analysis of Arcella intermedia and Arcella intermedia laevis (Amoebozoa, Arcellinida) illuminate phenotypic plasticity in microbial eukaryotes.

Science.gov (United States)

Porfírio-Sousa, Alfredo L; Ribeiro, Giulia M; Lahr, Daniel J G

2017-04-01

Testate amoebae are eukaryotic microorganisms characterized by the presence of an external shell (test). The shell morphology is used as a diagnostic character, but discordance between morphological and molecular data has been demonstrated in groups of arcellinids (Amoebozoa), one of the principal groups of testate amoebae. Morphology of the test is supposed to differentiate genera and species and it is applied in ecological, monitoring and paleontological studies. However, if phenotype does not reflect genotype, conclusions in these types of studies become severely impaired. The objective of this work is to evaluate the morphometrical and morphological variation of the closely related and morphologically similar taxa Arcella intermedia laevis Tsyganov and Mazei, 2006 and Arcella intermedia (Deflandre 1928) Tsyganov and Mazei, 2006 in nature and in cultured individuals and see how these are correlated with molecular data. Our results demonstrate that phenotypic plasticity in Arcella intermedia make morphological distinctions impossible in both taxa. Arcella intermedia and Arcella intermedia laevis are molecularly identical for SSU rDNA and a mitochondrial molecular marker (NAD9/7). We conclude that morphological techniques alone cannot identify phenotypic plasticity from natural populations. More work is clearly needed to better understand the morphological, morphometric and molecular variability in these organisms. Copyright © 2016 Elsevier GmbH. All rights reserved.

A unified anatomy ontology of the vertebrate skeletal system.

Science.gov (United States)

Dahdul, Wasila M; Balhoff, James P; Blackburn, David C; Diehl, Alexander D; Haendel, Melissa A; Hall, Brian K; Lapp, Hilmar; Lundberg, John G; Mungall, Christopher J; Ringwald, Martin; Segerdell, Erik; Van Slyke, Ceri E; Vickaryous, Matthew K; Westerfield, Monte; Mabee, Paula M

2012-01-01

The skeleton is of fundamental importance in research in comparative vertebrate morphology, paleontology, biomechanics, developmental biology, and systematics. Motivated by research questions that require computational access to and comparative reasoning across the diverse skeletal phenotypes of vertebrates, we developed a module of anatomical concepts for the skeletal system, the Vertebrate Skeletal Anatomy Ontology (VSAO), to accommodate and unify the existing skeletal terminologies for the species-specific (mouse, the frog Xenopus, zebrafish) and multispecies (teleost, amphibian) vertebrate anatomy ontologies. Previous differences between these terminologies prevented even simple queries across databases pertaining to vertebrate morphology. This module of upper-level and specific skeletal terms currently includes 223 defined terms and 179 synonyms that integrate skeletal cells, tissues, biological processes, organs (skeletal elements such as bones and cartilages), and subdivisions of the skeletal system. The VSAO is designed to integrate with other ontologies, including the Common Anatomy Reference Ontology (CARO), Gene Ontology (GO), Uberon, and Cell Ontology (CL), and it is freely available to the community to be updated with additional terms required for research. Its structure accommodates anatomical variation among vertebrate species in development, structure, and composition. Annotation of diverse vertebrate phenotypes with this ontology will enable novel inquiries across the full spectrum of phenotypic diversity.

The Intertropical Convergence Zone over the Middle East and North Africa: Detection and Trends

KAUST Repository

Scott, Anna A.

2013-05-01

This thesis provides an overview of identifying the Intertropical Convergence Zone (ITCZ) in the Middle East and North Africa (MENA) region. The ITCZ is a zone of wind convergence around the equator that coincides with an area of intense precipitation that is commonly termed a tropical rainbelt. In Africa, these two concepts are frequently confounded. This work studies the correlation between precipitation and commonly used ITCZ indicators. A further attempt is made to detect movement in the African ITCZ, based on earlier paleontological studies showing historical changes in precipitation. Zonally averaged wind convergence is found to be the most reliable indicator of the African ITCZ, one having a low correlation with zonally averaged precipitation. Precipitation is found only to be a reliable indicator for the African ITCZ in zones near the wind convergence, which reaches as far north as 20_N in the summer. No secular change in location of the African ITCZ is found for the time of available data. Finally, historical data shows that any increase in precipitation in the Sahel, a region where precipitation is driven by the ITCZ, is mildly negatively correlated with precipitation in the rainbelt area, suggesting that shifts in the ITCZ result in a widening of the precipitation profile as well as a shift of the entire zone.

Gaining the necessary geologic, hydrologic, and geochemical understanding for additional brackish groundwater development, coastal San Diego, California, USA

Science.gov (United States)

Danskin, Wesley R.

2012-01-01

Local water agencies and the United States Geological Survey are using a combination of techniques to better understand the scant freshwater resources and the much more abundant brackish resources in coastal San Diego, California, USA. Techniques include installation of multiple-depth monitoring well sites; geologic and paleontological analysis of drill cuttings; geophysical logging to identify formations and possible seawater intrusion; sampling of pore-water obtained from cores; analysis of chemical constituents including trace elements and isotopes; and use of scoping models including a three-dimensional geologic framework model, rainfall-runoff model, regional groundwater flow model, and coastal density-dependent groundwater flow model. Results show that most fresh groundwater was recharged during the last glacial period and that the coastal aquifer has had recurring intrusions of fresh and saline water. These intrusions disguise the source, flowpaths, and history of ground water near the coast. The flow system includes a freshwater lens resting on brackish water; a 100-meter-thick flowtube of freshwater discharging under brackish estuarine water and above highly saline water; and broad areas of fine-grained coastal sediment filled with fairly uniform brackish water. Stable isotopes of hydrogen and oxygen indicate the recharged water flows through many kilometers of fractured crystalline rock before entering the narrow coastal aquifer.

A Unified Anatomy Ontology of the Vertebrate Skeletal System

Science.gov (United States)

Dahdul, Wasila M.; Balhoff, James P.; Blackburn, David C.; Diehl, Alexander D.; Haendel, Melissa A.; Hall, Brian K.; Lapp, Hilmar; Lundberg, John G.; Mungall, Christopher J.; Ringwald, Martin; Segerdell, Erik; Van Slyke, Ceri E.; Vickaryous, Matthew K.; Westerfield, Monte; Mabee, Paula M.

2012-01-01

The skeleton is of fundamental importance in research in comparative vertebrate morphology, paleontology, biomechanics, developmental biology, and systematics. Motivated by research questions that require computational access to and comparative reasoning across the diverse skeletal phenotypes of vertebrates, we developed a module of anatomical concepts for the skeletal system, the Vertebrate Skeletal Anatomy Ontology (VSAO), to accommodate and unify the existing skeletal terminologies for the species-specific (mouse, the frog Xenopus, zebrafish) and multispecies (teleost, amphibian) vertebrate anatomy ontologies. Previous differences between these terminologies prevented even simple queries across databases pertaining to vertebrate morphology. This module of upper-level and specific skeletal terms currently includes 223 defined terms and 179 synonyms that integrate skeletal cells, tissues, biological processes, organs (skeletal elements such as bones and cartilages), and subdivisions of the skeletal system. The VSAO is designed to integrate with other ontologies, including the Common Anatomy Reference Ontology (CARO), Gene Ontology (GO), Uberon, and Cell Ontology (CL), and it is freely available to the community to be updated with additional terms required for research. Its structure accommodates anatomical variation among vertebrate species in development, structure, and composition. Annotation of diverse vertebrate phenotypes with this ontology will enable novel inquiries across the full spectrum of phenotypic diversity. PMID:23251424

Human (Clovis)–gomphothere (Cuvieronius sp.) association ∼13,390 calibrated yBP in Sonora, Mexico

Science.gov (United States)

Sanchez, Guadalupe; Holliday, Vance T.; Gaines, Edmund P.; Arroyo-Cabrales, Joaquín; Martínez-Tagüeña, Natalia; Kowler, Andrew; Lange, Todd; Hodgins, Gregory W. L.; Mentzer, Susan M.; Sanchez-Morales, Ismael

2014-01-01

The earliest known foragers to populate most of North America south of the glaciers [∼11,500 to ≥ ∼10,800 14C yBP; ∼13,300 to ∼12,800 calibrated (Cal) years] made distinctive “Clovis” artifacts. They are stereotypically characterized as hunters of Pleistocene megamammals (mostly mammoth) who entered the continent via Beringia and an ice-free corridor in Canada. The origins of Clovis technology are unclear, however, with no obvious evidence of a predecessor to the north. Here we present evidence for Clovis hunting and habitation ∼11,550 yBP (∼13,390 Cal years) at “El Fin del Mundo,” an archaeological site in Sonora, northwestern Mexico. The site also includes the first evidence to our knowledge for gomphothere (Cuvieronius sp.) as Clovis prey, otherwise unknown in the North American archaeological record and terminal Pleistocene paleontological record. These data (i) broaden the age and geographic range for Clovis, establishing El Fin del Mundo as one of the oldest and southernmost in situ Clovis sites, supporting the hypothesis that Clovis had its origins well south of the gateways into the continent, and (ii) expand the make-up of the North American megafauna community just before extinction. PMID:25024193

Human (Clovis)-gomphothere (Cuvieronius sp.) association ∼13,390 calibrated yBP in Sonora, Mexico

Science.gov (United States)

Sanchez, Guadalupe; Holliday, Vance T.; Gaines, Edmund P.; Arroyo-Cabrales, Joaquín; Martínez-Tagüeña, Natalia; Kowler, Andrew; Lange, Todd; Hodgins, Gregory W. L.; Mentzer, Susan M.; Sanchez-Morales, Ismael

2014-07-01

The earliest known foragers to populate most of North America south of the glaciers [∼11,500 to ≥ ∼10,800 14C yBP; ∼13,300 to ∼12,800 calibrated (Cal) years] made distinctive "Clovis" artifacts. They are stereotypically characterized as hunters of Pleistocene megamammals (mostly mammoth) who entered the continent via Beringia and an ice-free corridor in Canada. The origins of Clovis technology are unclear, however, with no obvious evidence of a predecessor to the north. Here we present evidence for Clovis hunting and habitation ∼11,550 yBP (∼13,390 Cal years) at "El Fin del Mundo," an archaeological site in Sonora, northwestern Mexico. The site also includes the first evidence to our knowledge for gomphothere (Cuvieronius sp.) as Clovis prey, otherwise unknown in the North American archaeological record and terminal Pleistocene paleontological record. These data (i) broaden the age and geographic range for Clovis, establishing El Fin del Mundo as one of the oldest and southernmost in situ Clovis sites, supporting the hypothesis that Clovis had its origins well south of the gateways into the continent, and (ii) expand the make-up of the North American megafauna community just before extinction.

Geological record of tsunami inundations in Pantano Morghella (south-eastern Sicily both from near and far-field sources

Directory of Open Access Journals (Sweden)

F. Gerardi

2012-04-01

Full Text Available Analysis of tsunami deposits from the Pantano Morghella area provided geological evidence for two inundations occurred along the south-eastern Ionian coast of Sicily. Pantano Morghella is a large pond characterised by a fine-grained sedimentation indicating a low-energy depositional environment. Two anomalous yellow sandy layers found at different depths indicate the occurrence of high-energy marine inundations. We studied sedimentological and paleontological features of the anomalous deposits as well as their spatial distribution observing the following properties: different facies with respect to the local stratigraphic sequence; erosive bases, rip-up clasts and broken elements testifying violent deposition mechanisms; macro and micro fauna of marine environment; relatively constant thickness throughout most of the depositional zone with thinning at the distal end; large sand sheets that extend inland. These observations, jointly with their infrequency in the sedimentary record and the age indicating a fast deposition, provided strong evidence for tsunami inundations. Correlations between anomalous layers and historical tsunamis are supported by radiocarbon and OSL dating results. The younger deposit is likely due to the 1908 near-source tsunami, whereas the flooding of the oldest event is most likely associated with a far and large source, the Crete 365 AD earthquake.

Corrected placement of Mus-Rattus fossil calibration forces precision in the molecular tree of rodents.

Science.gov (United States)

Kimura, Yuri; Hawkins, Melissa T R; McDonough, Molly M; Jacobs, Louis L; Flynn, Lawrence J

2015-09-28

Time calibration derived from the fossil record is essential for molecular phylogenetic and evolutionary studies. Fossil mice and rats, discovered in the Siwalik Group of Pakistan, have served as one of the best-known fossil calibration points in molecular phylogenic studies. Although these fossils have been widely used as the 12 Ma date for the Mus/Rattus split or a more basal split, conclusive paleontological evidence for the nodal assignments has been absent. This study analyzes newly recognized characters that demonstrate lineage separation in the fossil record of Siwalik murines and examines the most reasonable nodal placement of the diverging lineages in a molecular phylogenetic tree by ancestral state reconstruction. Our specimen-based approach strongly indicates that Siwalik murines of the Karnimata clade are fossil members of the Arvicanthini-Otomyini-Millardini clade, which excludes Rattus and its relatives. Combining the new interpretation with the widely accepted hypothesis that the Progonomys clade includes Mus, the lineage separation event in the Siwalik fossil record represents the Mus/Arvicanthis split. Our test analysis on Bayesian age estimates shows that this new calibration point provides more accurate estimates of murine divergence than previous applications. Thus, we define this fossil calibration point and refine two other fossil-based points for molecular dating.

Comparative anatomy, evolution, and homologies of tetrapod hindlimb muscles, comparison with forelimb muscles, and deconstruction of the forelimb-hindlimb serial homology hypothesis.

Science.gov (United States)

Diogo, Rui; Molnar, Julia

2014-06-01

For more than two centuries, the idea that the forelimb and hindlimb are serially homologous structures has been accepted without serious question. This study presents the first detailed analysis of the evolution and homologies of all hindlimb muscles in representatives of each major tetrapod group and proposes a unifying nomenclature for these muscles. These data are compared with information obtained previously about the forelimb muscles of tetrapods and the muscles of other gnathostomes in order to address one of the most central and enigmatic questions in evolutionary and comparative anatomy: why are the pelvic and pectoral appendages of gnathostomes generally so similar to each other? An integrative analysis of the new myological data, combined with a review of recent paleontological, developmental, and genetic works and of older studies, does not support serial homology between the structures of these appendages. For instance, many of the strikingly similar forelimb and hindlimb muscles found in each major extant tetrapod taxon were acquired at different geological times and/or have different embryonic origins. These similar muscles are not serial homologues, but the result of evolutionary parallelism/convergence due to a complex interplay of ontogenetic, functional, topological, and phylogenetic constraints/factors. Copyright © 2014 Wiley Periodicals, Inc.

Geochemical and rare earth elements distribution pattern in gaiman F M.phosphatic levels, Chubu t, Argentina

International Nuclear Information System (INIS)

Castro, L.; Fazio, A.; Tourn, S.; Scasso, R.

2004-01-01

Phosphatic concretions in the Early Miocene marine sediments of the Gaiman Formation (Miocene) were analyzed for rare earth elements (REE), in order to discuss their pattern in the context of paleoenvironmental interpretations. P2O5 in concretions is between 15,61 to 21,82%. Two types of concretions are found: Type 1 represented by in situ ones developed within transgressive-early highstand system tracts which shows little evidence for significant transportation, and Type 2 related to reworking, winnowing and mechanical concentration of resistant particles. Type 1 exhibits higher REE/P ratios and a significant enrichment in HREE than Type 2. The REE pattern in both shows a slight depletion in LREE with a weak Ce anomaly (-0.08 to 0.04), and an enrichment in high rare earth elements, in comparison to the a verage shale. Their mean content in REE (915 ppm) and Y (500 ppm) doubles the worldwide phosphorite average (462 ppm and 275 ppm). No significant correlation is found between REEs and P2O5. On the other hand, HREE enrichment (Lu/Ce) increases with the REEs bulk content. The pattern is consistent with shallow water inner shelf marine environment which is also suggested by sedimentological and paleontological evidence [es

Gamma-ray spectra from the age of the dinosaurs

International Nuclear Information System (INIS)

Johnson, M.W.

1994-01-01

Gamma-ray spectroscopy has been tested as a technique for assisting in the excavation of paleontological sites in the Morrison Formation of western New Mexico. Excavation of these sites is difficult, owing to remoteness and to environmental concerns that militate against wholesale removal of overburden. Various researchers have used remote-sensing techniques to attempt to locate sub-surface bone near known, exposed fossils, thereby to confine excavation to areas where success in finding bone is most likely. Bones accumulate uranium from surrounding rock during fossilization; accordingly, in-situ gamma-ray spectroscopy might serve to locate bone, by detecting the 609- and 1764-keV gamma rays from uranium daughters. Because of the high uranium content of fossils in the Morrison Formation, calculations suggest the feasibility of locating bone despite the presence of several cm of rock and soil overburden. Investigations at several sites with fossils of large sauropods have revealed increased count rates for the key gamma rays near exposed bone, possibly implying the presence of additional fossils beneath the surface of the ground. However, attempts to use spectroscopy inside shafts drilled into possible fossil-bearing rock have been less successful. Results are presented and prospects for additional work discussed

Revelation and registration of geological heritage on the test sites territories

International Nuclear Information System (INIS)

Kazakova, Yu.I.

1999-01-01

Studies of geotypes in Kazakhstan are carrying out from 1993. 'Geological heritage of Kazakhstan' data base incorporating more than 400 objects is developed. The geotypes classification by a diverse features was worked out. The showing up and accounting system of geotype objects diversity was demonstrated and approved on the international symposia on geological heritage protection (ProGeo-97 and ProGeo-98). But this work does not conducted on the test sites yet. At present these territories have been more available but data about geotypes within its boundaries are fragmentary yet. Among its there are locations of interesting dinosaur remains (Baikanur space site), ancient mine working, petroglyphic drawings, agate manifestations, picturesque landscapes (Semipalatinsk test site). Within test zones there are such interesting antropogenic noticeably object as places of nuclear explosions including the famous Atomic Lake. There are a lot interest object on the territories adjoint to test sites (stratigraphical open-casts of the universal importance, paleontological remains and others) gives basis for to suggest that on the closed earlier territories there are a lot of interesting geotypes. At present these sites are entering to rehabilitation stage. At that one of the important measure must be study of geotypes situated within its limits

Substantive uniformitarianism and Darwinism

Energy Technology Data Exchange (ETDEWEB)

Hsu, K.J.

1985-01-01

Darwin's theory of evolution has two themes: common descent and natural selection. The first has been controversial from the beginning to the present day, but is now well supported by geological and biological evidence. The idea of natural selection was inspired by Malthus' Essay on the Principle of Population and by the Weltanschauung of his time. Geological evidence, commonly negative, was dismissed as artifact of imperfect geological record. Variation, adaptation, and survival of the fittest are the three steps of natural selection. Adaptation implies the presence of stable environments as the goal; changes, if any, had to be gradual, slow enough for organisms to adapt. The definition of fitness also depends upon frame of reference; fitness has no meaning in a rapidly changing world. Recent geochemical, sedimentological, and paleontological studies revealed past occurrences of convulsive environmental changes as probably causes of biotic crises. Extinction was often not, as Darwin believed, the consequence of multiplication of species and selection of the fittest. Extinction could be the cause of several episodes of accelerated evolution when ecologic niches had been liberated after a catastrophe. The geological investigations of the century after Darwin indicated the inadequacy of those ideas which had been postulated on the basis of social philosophy.

The Paleozoic ichthyofauna of the Amazonas and Parnaíba basins, Brazil

Science.gov (United States)

Figueroa, Rodrigo Tinoco; Machado, Deusana Maria da Costa

2018-03-01

The Brazilian Paleozoic ichthyofauna from the Parnaíba and Amazonas basins regard a sparsely known diversity, including chondrichthyans and acanthodians, besides some osteichthyan remains. This work proposes a revision of the fossil material from these two sedimentary basins and synthesizes the morphological aspect of such material trying to understand the influences of those fossils to the paleontology of the region, comparing the Brazilian fossils with other gondwanan faunas. The Brazilian Paleozoic fish fauna shows great resemblance to those of Bolivia, especially during the Devonian. Many of the Acanthodian spines from the Manacapuru Formation (Amazonas Basin), and the Pimenteira Formation (Parnaíba Basin), are comparable to the taxa found in Bolivia. The lack of more Placoderm remains in the Brazilian outcrops is similar to the low diversity of this group in Bolivia, when compared to other South American and Euramerican localities. The most diverse Brazilian ichthyofauna is encountered in the Permian Pedra de Fogo Formation where numerous chondrichthyans and 'paleopterygians' remains are found, together with dipnoans and actinistians. Despite the apparent lack of more representative Paleozoic ichthyofaunas in Brazil, the available material that ranges from Lower Devonian to early Permian from Brazil bears important taxa that could address valuable taxonomic and biogeographic informations.

Age of Mammuthus trogontherii from Kostolac, Serbia, and the entry of megaherbivores into Europe during the Late Matuyama climate revolution

Science.gov (United States)

Muttoni, Giovanni; Scardia, Giancarlo; Dimitrijević, Vesna; Kent, Dennis V.; Monesi, Edoardo; Mrdjić, Nemanja; Korać, Miomir

2015-11-01

At the Drmno open-pit coal mine near Kostolac in Serbia, a nearly complete skeleton of Mammuthus trogontherii (nicknamed Vika) was discovered in a fluvial deposit overlain by a loess-paleosol sequence where a second paleontological level named Nosak with remains of M. trogontherii was found. We studied the magnetostratigraphy of the Kostolac sedimentary sequence and found that the Vika layer dates to 0.8 Ma, shortly before the Brunhes-Matuyama boundary. In addition, according to our age model and previously reported optically stimulated luminescence and electron spin resonance dates, the Nosak fossils have an estimated age of 0.19 Ma and lived during the earliest part of Marine Isotope Stage 6. It appears therefore that at Kostolac, M. trogontherii is preserved both at its earliest occurrence at 0.8 Ma and close to its latest occurrence at 0.19 Ma, and may well have been present in between, albeit not yet found. We speculate that megaherbivores such as M. trogontherii entered Europe along a conjunct Danube-Po River migration conduit connecting western Asia-Levant with central-southern Europe where vast and exploitable ecosystems, particularly suited for steppe- or savanna-adapted megaherbivores from Asia and Africa, developed during the late early Pleistocene climate revolution at around 0.8 Ma.

New Information about Albert Einstein's Brain.

Science.gov (United States)

Falk, Dean

2009-01-01

In order to glean information about hominin (or other) brains that no longer exist, details of external neuroanatomy that are reproduced on endocranial casts (endocasts) from fossilized braincases may be described and interpreted. Despite being, of necessity, speculative, such studies can be very informative when conducted in light of the literature on comparative neuroanatomy, paleontology, and functional imaging studies. Albert Einstein's brain no longer exists in an intact state, but there are photographs of it in various views. Applying techniques developed from paleoanthropology, previously unrecognized details of external neuroanatomy are identified on these photographs. This information should be of interest to paleoneurologists, comparative neuroanatomists, historians of science, and cognitive neuroscientists. The new identifications of cortical features should also be archived for future scholars who will have access to additional information from improved functional imaging technology. Meanwhile, to the extent possible, Einstein's cerebral cortex is investigated in light of available data about variation in human sulcal patterns. Although much of his cortical surface was unremarkable, regions in and near Einstein's primary somatosensory and motor cortices were unusual. It is possible that these atypical aspects of Einstein's cerebral cortex were related to the difficulty with which he acquired language, his preference for thinking in sensory impressions including visual images rather than words, and his early training on the violin.

The lunar nodal tide and the distance to tne Moon during the Precambrian era

Science.gov (United States)

Walker, J. C. G.; Zahnle, K. J.

1986-01-01

The origin and early evolution of life on Earth occurred under physical and chemical conditions distinctly different from those of the present day. The broad goal of this research program is to characterize these conditions. One aspect involves the dynamics of the Earth-Moon system, the distance of the Moon from the Earth, and the length of the day. These have evolved during the course of Earth history as a result of the dissipation of tidal energy. As the moon has receded the amplitude of oceanic tides has decreased while the increasing length of the day should have influenced climate and the circulation of atmosphere and ocean. A 23.3 year periodicity preserved in a 2500 million year old banded iron-formation was interpreted as reflecting the climatic influence of the lunar nodal tide. The corresponding lunar distance would then have been approx. 52 Earth radii. The influence of the lunar nodal tide is also apparent in rocks with an age of 680 million years B.P. The derived value for lunar distance 2500 million years ago is the only datum on the dynamics of the Earth-Moon system during the Precambrian era of Earth history. The implied development of Precambrian tidal friction is in accord with more recent paleontological evidence as well as the long term stability of the lunar orbit.

Proxy records of Holocene storm events in coastal barrier systems: Storm-wave induced markers

Science.gov (United States)

Goslin, Jérôme; Clemmensen, Lars B.

2017-10-01

Extreme storm events in the coastal zone are one of the main forcing agents of short-term coastal system behavior. As such, storms represent a major threat to human activities concentrated along the coasts worldwide. In order to better understand the frequency of extreme events like storms, climate science must rely on longer-time records than the century-scale records of instrumental weather data. Proxy records of storm-wave or storm-wind induced activity in coastal barrier systems deposits have been widely used worldwide in recent years to document past storm events during the last millennia. This review provides a detailed state-of-the-art compilation of the proxies available from coastal barrier systems to reconstruct Holocene storm chronologies (paleotempestology). The present paper aims (I) to describe the erosional and depositional processes caused by storm-wave action in barrier and back-barrier systems (i.e. beach ridges, storm scarps and washover deposits), (ii) to understand how storm records can be extracted from barrier and back-barrier sedimentary bodies using stratigraphical, sedimentological, micro-paleontological and geochemical proxies and (iii) to show how to obtain chronological control on past storm events recorded in the sedimentary successions. The challenges that paleotempestology studies still face in the reconstruction of representative and reliable storm-chronologies using these various proxies are discussed, and future research prospects are outlined.

Cardiorespiratory interactions previously identified as mammalian are present in the primitive lungfish.

Science.gov (United States)

Monteiro, Diana A; Taylor, Edwin W; Sartori, Marina R; Cruz, André L; Rantin, Francisco T; Leite, Cleo A C

2018-02-01

The present study has revealed that the lungfish has both structural and functional features of its system for physiological control of heart rate, previously considered solely mammalian, that together generate variability (HRV). Ultrastructural and electrophysiological investigation revealed that the nerves connecting the brain to the heart are myelinated, conferring rapid conduction velocities, comparable to mammalian fibers that generate instantaneous changes in heart rate at the onset of each air breath. These respiration-related changes in beat-to-beat cardiac intervals were detected by complex analysis of HRV and shown to maximize oxygen uptake per breath, a causal relationship never conclusively demonstrated in mammals. Cardiac vagal preganglionic neurons, responsible for controlling heart rate via the parasympathetic vagus nerve, were shown to have multiple locations, chiefly within the dorsal vagal motor nucleus that may enable interactive control of the circulatory and respiratory systems, similar to that described for tetrapods. The present illustration of an apparently highly evolved control system for HRV in a fish with a proven ancient lineage, based on paleontological, morphological, and recent genetic evidence, questions much of the anthropocentric thinking implied by some mammalian physiologists and encouraged by many psychobiologists. It is possible that some characteristics of mammalian respiratory sinus arrhythmia, for which functional roles have been sought, are evolutionary relics that had their physiological role defined in ancient representatives of the vertebrates with undivided circulatory systems.

Revised Cretaceous and Tertiary stratigraphic nomenclature in the Colville Basin, Northern Alaska

Science.gov (United States)

Mull, Charles G.; Houseknecht, David W.; Bird, Kenneth J.

2003-01-01

A revised stratigraphic nomenclature is proposed for Cretaceous and Tertiary geologic units of the central and western North Slope of Alaska. This revised nomenclature is a simplified and broadly applicable scheme suitable for a suite of digital geologic quadrangle maps being prepared jointly by the U.S. Geological Survey and the Alaska Department of Natural Resources, Division of Geological and Geophysical Surveys and Division of Oil and Gas. This revised nomenclature scheme is a simplification of a complex stratigraphic terminology that developed piecemeal during five decades of geologic investigations of the North Slope. It is based on helicopter-supported geologic field investigations incorporating information from high-resolution aerial photography, satellite imagery, paleontology, reflection seismic records, and sequence stratigraphic concepts. This revised nomenclature proposes the abandonment of the Colville Group; demotion of the Nanushuk Group to formation status; abandonment of six formations (Kukpowruk, Tuktu, Grandstand, Corwin, Chandler, and Ninuluk); revision of four formations (Sagavanirktok, Prince Creek, Schrader Bluff, and Seabee); elevation of the Tuluvak Tongue of the Prince Creek Formation to formation status; revision of two members (Franklin Bluffs Member and Sagwon Member of the Sagavanirktok Formation); abandonment of eight members or tongues (Kogosukruk, Rogers Creek, Barrow Trail, Sentinel Hill, Ayiyak, Shale Wall, Niakogon, and Killik); and definition of one new member (White Hills Member of the Sagavanirktok Formation).

The ornithologist Alfred Russel Wallace and the controversy surrounding the dinosaurian origin of birds.

Science.gov (United States)

Ibrahim, Nizar; Kutschera, Ulrich

2013-12-01

Over many years of his life, the British naturalist Alfred Russel Wallace (1823-1913) explored the tropical forests of Malaysia, collecting numerous specimens, including hundreds of birds, many of them new to science. Subsequently, Wallace published a series of papers on systematic ornithology, and discovered a new species on top of a volcano on Ternate, where he wrote, in 1858, his famous essay on natural selection. Based on this hands-on experience, and an analysis of an Archaeopteryx fossil, Wallace suggested that birds may have descended from dinosaurian ancestors. Here, we describe the "dinosaur-bird hypothesis" that originated with the work of Thomas H. Huxley (1825-1895). We present the strong evidence linking theropod dinosaurs to birds, and briefly outline the long and ongoing controversy around this concept. Dinosaurs preserving plumage, nesting sites and trace fossils provide overwhelming evidence for the dinosaurian origin of birds. Based on these recent findings of paleontological research, we conclude that extant birds indeed descended, with some modifications, from small, Mesozoic theropod dinosaurs. In the light of Wallace's view of bird origins, we critically evaluate recent opposing views to this idea, including Ernst Mayr's (1904-2005) arguments against the "dinosaur-bird hypothesis", and document that this famous ornithologist was not correct in his assessment of this important aspect of vertebrate evolution.

Neutrino radiation hazards: A paper tiger

International Nuclear Information System (INIS)

Cossairt, J.D.; Grossman, N.L.; Marshall, E.T.

1996-09-01

Neutrinos are present in the natural environment due to terrestrial, solar, and cosmic sources and are also produced at accelerators both incidentally and intentionally as part of physics research programs. Progress in fundamental physics research has led to the creation of beams of neutrinos of ever-increasing intensity and/or energy. The large size and cost associated with these beams attracts, and indeed requires, public interest, support, and some understanding of the 'exotic' particles produced, including the neutrinos. Furthermore, the very word neutrino ('little neutral one', as coined by Enrico Fermi) can lead to public concern due to confusion with 'neutron', a word widely associated with radiological hazards. Adding to such possible concerns is a recent assertion, widely publicized, that neutrinos from astronomical events may have led to the extinction of some biological species. Presented here are methods for conservatively estimating the dose equivalent due to neutrinos as well as an assessment of the possible role of neutrinos in biological extinction processes. It is found that neutrinos produced by the sun and modern particle accelerators produce inconsequential dose equivalent rates. Examining recent calculations concerning neutrinos incident upon the earth due to stellar collapse, it is concluded that it is highly unlikely that these neutrinos caused the mass extinctions of species found in the paleontological record. Neutrino radiation hazards are, then, truly a 'paper tiger'. 14 refs., 1 fig., 1 tab

Association of anatase (TiO2) and microbes: unusual fossilization effect or a potential biosignature?

Science.gov (United States)

Glamoclija, Mihaela; Andrew Steele,; Marc Fries,; Juergen Schieber,; Voytek, Mary A.; Charles S. Cockell,

2015-01-01

We combined microbial paleontology and molecular biology methods to study the Eyreville B drill core from the 35.3-Ma-old Chesapeake Bay impact structure,Virginia, USA. The investigated sample is a pyrite vein collected from the 1353.81-1353.89 m depth interval, located within a section of biotite granite. The granite is a pre-impact rock that was disrupted by the impact event. A search for inorganic (mineral) biosignatures revealed the presence of micron-size rod morphologies of anatase (TiO2) embedded in chlorite coatings on pyrite grains. Neither the Acridine Orange microbial probe nor deoxyribonucleic acid (DNA) extraction followed by polymerase chain reaction (PCR) amplifi cation showed the presence of DNA or ribonucleic acid (RNA) at the location of anatase rods, implying the absence of viable cells in the investigated area. A Nile Red microbial probe revealed the presence of lipids in the rods. Because most of the lipids are resistant over geologic time spans, they are good biomarkers, and they are an indicator of biogenicity for these possibly 35-Ma-old microbial fossils. The mineral assemblage suggests that rod morphologies are associated with low-temperature (<100 °C) hydrothermal alteration that involved aqueous fl uids. The temporal constraints on the anatase fossils are still uncertain because pre-impact alteration of the granite and postimpact heating may have provided identical conditions for anatase precipitation and microbial preservation.

The Gavialis-Tomistoma debate: the contribution of skull ontogenetic allometry and growth trajectories to the study of crocodylian relationships.

Science.gov (United States)

Piras, Paolo; Colangelo, Paolo; Adams, Dean C; Buscalioni, Angela; Cubo, Jorge; Kotsakis, Tassos; Meloro, Carlo; Raia, Pasquale

2010-01-01

The phylogenetic placement of Tomistoma and Gavialis crocodiles depends largely upon whether molecular or morphological data are utilized. Molecular analyses consider them as sister taxa, whereas morphological/paleontological analyses set Gavialis apart from Tomistoma and other crocodylian species. Here skull allometric trajectories of Tomistoma and Gavialis were contrasted with those of two longirostral crocodylian taxa, Crocodylus acutus and Mecistops cataphractus, to examine similarities in growth trajectories in light of this phylogenetic controversy. Entire skull shape and its two main modules, rostrum and postrostrum, were analyzed separately. We tested differences for both multivariate angles between trajectories and for shape differences at early and late stages of development. Based on a multivariate regression of shape data and size, Tomistoma seems to possess a peculiar rate of growth in comparison to the remaining taxa. However, its morphology at both juvenile and adult sizes is always closer to those of Brevirostres crocodylians, for the entire head shape, as well as the shape of the postrostrum and rostrum. By contrast, the allometric trajectory of Gavialis always begins and ends in a unique region of the multidimensional morphospace. These findings concur with a morphological hypothesis that places Gavialis separate from Brevirostres, and Tomistoma closer to other crocodylids, and provides an additional, and independent, data set to inform on this ongoing phylogenetic discussion. © 2010 Wiley Periodicals, Inc.

Grene and Hull on types and typological thinking in biology.

Science.gov (United States)

Honenberger, Phillip

2015-04-01

Marjorie Grene (1910-2009) and David Hull (1935-2010) were among the most influential voices in late twentieth-century philosophy of biology. But, as Grene and Hull pointed out in published discussions of one another's work over the course of nearly forty years, they disagreed strongly on fundamental issues. Among these contested issues is the role of what is sometimes called "typology" and "typological thinking" in biology. In regard to taxonomy and the species problem, Hull joined Ernst Mayr's construal of typological thinking as a backward relic of pre-Darwinian science that should be overcome. Grene, however, treated the suspicion of typological thinking that characterized Hull's views, as well as those of other architects of the New Evolutionary Synthesis, as itself suspicious and even unsustainable. In this paper I review three debates between Grene and Hull bearing on the question of the validity of so-called typological thinking in biology: (1) a debate about the dispensability of concepts of "type" within evolutionary theory, paleontology, and taxonomy; (2) a debate about whether species can be adequately understood as individuals, and thereby independently of those forms of thinking Hull and Mayr had construed as "typological"; and (3) a debate about the prospects of a biologically informed theory of human nature. Copyright © 2015 Elsevier Ltd. All rights reserved.

SIVALHIPPUS PTYCHODUS AND SIVALHIPPUS PLATYODUS (PERISSODACTYLA, MAMMALIA FROM THE LATE MIOCENE OF CHINA

Directory of Open Access Journals (Sweden)

BOYANG SUN

2018-01-01

Full Text Available Herein, the authors report on skulls, mandibles and postcranial specimens of two species of Chinese Sivalhippus, S. ptychodus and S. platyodus. We frame our description and analyses within the context of newly described characters of the cheek teeth of Hippotherium from the Pannonian C of the Vienna Basin, the oldest and most primitive Old World hipparions. Our report includes original skull, mandibular and limited postcranial material of Sivalhippus ptychodus and skulls and dentitions of Sivalhippus platyodus from the Paleontological Museum of Uppsala (PMU, Uppsala, Sweden, the American Museum of Natural History (AMNH, New York, USA and the Licent Collection in Tianjin Natural History Museum (Tianjin, China. The skull, maxillary and mandibular material we attribute to Sivalhippus ptychodus and Sivalhippus platyodus exhibit some primitive features for Old World hipparions and synapamorphies of the face and dentition that unite it with the Sivalhippus clade. Our analysis shows that S. ptychodus and S. platyodus differ significantly from the Cormohipparion occidentale – Hippotherium primigenium clade. Species belonging to the Sivalhippus clade are found in IndoPakistan (S. nagriensis, S. theobaldi, S. perimensis and S. anwari, Libya and Kenya (S. turkanensis and Uganda (S. macrodon. We hypothesize that the Sivalhippus clade originated in South Asia where it is earliest represented by Sivalhipus nagriensis, ca. 10.4 Ma and underwent range extension into Africa and China circa 9-7 Ma.

Reptile and rodent parasites in raptor pellets in an archaeological context: the case of Epullán Chica (northwestern Patagonia, Argentina)

Science.gov (United States)

Beltrame, María Ornela; Fernández, Fernando Julián; Sardella, Norma Haydeé

2015-07-01

Paleoparasitology is the study of parasite remains from archaeological and paleontological sites. Raptor pellets can be used as source for paleoparasitological information in archaeological sites. However, this zooarchaeological material has been scarcely studied. Epullán Chica (ECh) is an archaeological site in northwestern Patagonia. This cave yielded remains from more than 2000 years before present. The aim of this paper was to study the parasite remains found in owl pellets from the archaeological site ECh, and to discuss the paleoparasitological findings in an archaeological context. Twenty two raptor pellets were examined for parasites. The pellets were whole processed by rehydration in a 0.5% water solution of trisodium phosphate, followed by homogenization, filtered and processed by spontaneous sedimentation. Eight out of 22 bird pellets examined were positive for parasites from reptiles and rodents. Representatives of 12 parasite taxa were recorded; nine of this parasitic species were reported for the first time from ancient samples from Patagonia. This is the first time that pellets give evidences of ancient reptile parasites from archaeological contexts. It is noteworthy that Late Holocene hunter-gatherers of the upper Limay River basin, could have been exposed to some of these zoonotic parasites. Future paleoparasitological studies on owl pellets may reflect even more the parasitological diversity of all micromammal and reptile species presents in ancient times.

Cardiorespiratory interactions previously identified as mammalian are present in the primitive lungfish

Science.gov (United States)

Monteiro, Diana A.; Taylor, Edwin W.; Sartori, Marina R.; Cruz, André L.; Rantin, Francisco T.; Leite, Cleo A. C.

2018-01-01

The present study has revealed that the lungfish has both structural and functional features of its system for physiological control of heart rate, previously considered solely mammalian, that together generate variability (HRV). Ultrastructural and electrophysiological investigation revealed that the nerves connecting the brain to the heart are myelinated, conferring rapid conduction velocities, comparable to mammalian fibers that generate instantaneous changes in heart rate at the onset of each air breath. These respiration-related changes in beat-to-beat cardiac intervals were detected by complex analysis of HRV and shown to maximize oxygen uptake per breath, a causal relationship never conclusively demonstrated in mammals. Cardiac vagal preganglionic neurons, responsible for controlling heart rate via the parasympathetic vagus nerve, were shown to have multiple locations, chiefly within the dorsal vagal motor nucleus that may enable interactive control of the circulatory and respiratory systems, similar to that described for tetrapods. The present illustration of an apparently highly evolved control system for HRV in a fish with a proven ancient lineage, based on paleontological, morphological, and recent genetic evidence, questions much of the anthropocentric thinking implied by some mammalian physiologists and encouraged by many psychobiologists. It is possible that some characteristics of mammalian respiratory sinus arrhythmia, for which functional roles have been sought, are evolutionary relics that had their physiological role defined in ancient representatives of the vertebrates with undivided circulatory systems. PMID:29507882

Influence of Tertiary paleoenvironmental changes on the diversification of South American mammals: a relaxed molecular clock study within xenarthrans

Directory of Open Access Journals (Sweden)

Vizcaíno Sergio F

2004-04-01

Full Text Available Abstract Background Comparative genomic data among organisms allow the reconstruction of their phylogenies and evolutionary time scales. Molecular timings have been recently used to suggest that environmental global change have shaped the evolutionary history of diverse terrestrial organisms. Living xenarthrans (armadillos, anteaters and sloths constitute an ideal model for studying the influence of past environmental changes on species diversification. Indeed, extant xenarthran species are relicts from an evolutionary radiation enhanced by their isolation in South America during the Tertiary era, a period for which major climate variations and tectonic events are relatively well documented. Results We applied a Bayesian approach to three nuclear genes in order to relax the molecular clock assumption while accounting for differences in evolutionary dynamics among genes and incorporating paleontological uncertainties. We obtained a molecular time scale for the evolution of extant xenarthrans and other placental mammals. Divergence time estimates provide substantial evidence for contemporaneous diversification events among independent xenarthran lineages. This correlated pattern of diversification might possibly relate to major environmental changes that occurred in South America during the Cenozoic. Conclusions The observed synchronicity between planetary and biological events suggests that global change played a crucial role in shaping the evolutionary history of extant xenarthrans. Our findings open ways to test this hypothesis further in other South American mammalian endemics like hystricognath rodents, platyrrhine primates, and didelphid marsupials.

Reconstructing past ecological networks: the reconfiguration of seed-dispersal interactions after megafaunal extinction.

Science.gov (United States)

Pires, Mathias M; Galetti, Mauro; Donatti, Camila I; Pizo, Marco A; Dirzo, Rodolfo; Guimarães, Paulo R

2014-08-01

The late Quaternary megafaunal extinction impacted ecological communities worldwide, and affected key ecological processes such as seed dispersal. The traits of several species of large-seeded plants are thought to have evolved in response to interactions with extinct megafauna, but how these extinctions affected the organization of interactions in seed-dispersal systems is poorly understood. Here, we combined ecological and paleontological data and network analyses to investigate how the structure of a species-rich seed-dispersal network could have changed from the Pleistocene to the present and examine the possible consequences of such changes. Our results indicate that the seed-dispersal network was organized into modules across the different time periods but has been reconfigured in different ways over time. The episode of megafaunal extinction and the arrival of humans changed how seed dispersers were distributed among network modules. However, the recent introduction of livestock into the seed-dispersal system partially restored the original network organization by strengthening the modular configuration. Moreover, after megafaunal extinctions, introduced species and some smaller native mammals became key components for the structure of the seed-dispersal network. We hypothesize that such changes in network structure affected both animal and plant assemblages, potentially contributing to the shaping of modern ecological communities. The ongoing extinction of key large vertebrates will lead to a variety of context-dependent rearranged ecological networks, most certainly affecting ecological and evolutionary processes.

Heterochronic truncation of odontogenesis in theropod dinosaurs provides insight into the macroevolution of avian beaks.

Science.gov (United States)

Wang, Shuo; Stiegler, Josef; Wu, Ping; Chuong, Cheng-Ming; Hu, Dongyu; Balanoff, Amy; Zhou, Yachun; Xu, Xing

2017-10-10

Beaks are innovative structures characterizing numerous tetrapod lineages, including birds, but little is known about how developmental processes influenced the macroevolution of these important structures. Here we provide evidence of ontogenetic vestigialization of alveoli in two lineages of theropod dinosaurs and show that these are transitional phenotypes in the evolution of beaks. One of the smallest known caenagnathid oviraptorosaurs and a small specimen of the Early Cretaceous bird Sapeornis both possess shallow, empty vestiges of dentary alveoli. In both individuals, the system of vestiges connects via foramina with a dorsally closed canal homologous to alveoli. Similar morphologies are present in Limusaurus , a beaked theropod that becomes edentulous during ontogeny; and an analysis of neontological and paleontological evidence shows that ontogenetic reduction of the dentition is a relatively common phenomenon in vertebrate evolution. Based on these lines of evidence, we propose that progressively earlier postnatal and embryonic truncation of odontogenesis corresponds with expansion of rostral keratin associated with the caruncle, and these progenesis and peramorphosis heterochronies combine to drive the evolution of edentulous beaks in nonavian theropods and birds. Following initial apomorphic expansion of rostral keratinized epithelia in perinatal toothed theropods, beaks appear to inhibit odontogenesis as they grow postnatally, resulting in a sequence of common morphologies. This sequence is shifted earlier in development through phylogeny until dentition is absent at hatching, and odontogenesis is inhibited by beak formation in ovo .

On the antiquity of language: the reinterpretation of Neandertal linguistic capacities and its consequences

Science.gov (United States)

Dediu, Dan; Levinson, Stephen C.

2013-01-01

It is usually assumed that modern language is a recent phenomenon, coinciding with the emergence of modern humans themselves. Many assume as well that this is the result of a single, sudden mutation giving rise to the full “modern package.” However, we argue here that recognizably modern language is likely an ancient feature of our genus pre-dating at least the common ancestor of modern humans and Neandertals about half a million years ago. To this end, we adduce a broad range of evidence from linguistics, genetics, paleontology, and archaeology clearly suggesting that Neandertals shared with us something like modern speech and language. This reassessment of the antiquity of modern language, from the usually quoted 50,000–100,000 years to half a million years, has profound consequences for our understanding of our own evolution in general and especially for the sciences of speech and language. As such, it argues against a saltationist scenario for the evolution of language, and toward a gradual process of culture-gene co-evolution extending to the present day. Another consequence is that the present-day linguistic diversity might better reflect the properties of the design space for language and not just the vagaries of history, and could also contain traces of the languages spoken by other human forms such as the Neandertals. PMID:23847571

Más allá del valle del Rift: la evidencia arqueológica del Plio-Pleistoceno fuera de África Oriental

Directory of Open Access Journals (Sweden)

Ignacio de la TORRE SÁINZ

2009-12-01

Full Text Available RESUMEN: La mayor parte de los trabajos sobre la arqueología del Plio-Pleistoceno en Africa se centran en la evidencia del valle del Rift. Allí existen extensas columnas crono-estratigráficas que permiten contextualizar de forma fiable los conjuntos arqueo-paleontológicos y reconstruir así la secuencia evolutiva de nuestro género. Se suele obviar de esa forma la evidencia del resto de África, donde existen grandes áreas sedimentarias muy poco conocidas desde un punto de vista arqueológico. En este trabajo se reflexionará sobre el registro arqueológico plio-pleistocénico en las zonas alejadas del valle del Rift, y se tratará de reconstruir cómo fue la primera colonización del continente africano.ABSTRACT: Most of the works about the African Plio-Pleistocene are focused on the Rift Valley evidence. In this area there are long chrono-stratigraphical columns that build reliable contexts for the archaeo-paleontological sites, providing the reconstruction of the evolutionary sequence of our Genus. Evidence on the rest of Africa, where there are poor-known sedimentary areas from an archaeological point of view, is usually dismissed. In this work we will reflect on the Plio-Pleistocene record beyond the Rift Valley, trying to reconstruct the first settlement of the African continent.

Integrated analyses resolve conflicts over squamate reptile phylogeny and reveal unexpected placements for fossil taxa.

Directory of Open Access Journals (Sweden)

Tod W Reeder

Full Text Available Squamate reptiles (lizards and snakes are a pivotal group whose relationships have become increasingly controversial. Squamates include >9000 species, making them the second largest group of terrestrial vertebrates. They are important medicinally and as model systems for ecological and evolutionary research. However, studies of squamate biology are hindered by uncertainty over their relationships, and some consider squamate phylogeny unresolved, given recent conflicts between molecular and morphological results. To resolve these conflicts, we expand existing morphological and molecular datasets for squamates (691 morphological characters and 46 genes, for 161 living and 49 fossil taxa, including a new set of 81 morphological characters and adding two genes from published studies and perform integrated analyses. Our results resolve higher-level relationships as indicated by molecular analyses, and reveal hidden morphological support for the molecular hypothesis (but not vice-versa. Furthermore, we find that integrating molecular, morphological, and paleontological data leads to surprising placements for two major fossil clades (Mosasauria and Polyglyphanodontia. These results further demonstrate the importance of combining fossil and molecular information, and the potential problems of estimating the placement of fossil taxa from morphological data alone. Thus, our results caution against estimating fossil relationships without considering relevant molecular data, and against placing fossils into molecular trees (e.g. for dating analyses without considering the possible impact of molecular data on their placement.