نتایج جستجو برای: fossil record
تعداد نتایج: 121933 فیلتر نتایج به سال:
The Cambrian explosion can be thought of as the culmination of a diversification of eukaryotes that had begun several hundred million years before. Eukaryotes – one of the three domains of life — originated by late Archean time, and probably underwent a long period of stem group evolution during the Paleoproterozoic Era. A suite of taxonomically resolved body fossils and biomarkers, together wi...
Fossils provide the only direct evidence of the evolutionary history of primates. A method of phylogeny reconstruction is outlined which is based on an evaluation ofphenetic resemblances of fossils interpreted in their stratigraphiccontext. This stratopheneti¢ approach to phylogeny involves three successive steps: (1) organization of fossils stratigraphically, (2) phenetie linking of similar fo...
Of all of the sources of evidence for evolution by natural selection, perhaps the most problematic for Darwin was the geological record of organic change. In response to the absence of species-level transformations in the fossil record, Darwin argued that the fossil record was too incomplete, too biased, and too poorly known to provide strong evidence against his theory. Here, this view of the ...
Differentiation between Neotropical rainforest, dry forest, and savannah ecosystems by their modern pollen spectra and implications for the fossil pollen record Journal Article How to cite: Gosling, William D.; Mayle, Francis E.; Tate, Nicholas J. and Killeen, Timothy J. (2009). Differentiation between Neotropical rainforest, dry forest, and savannah ecosystems by their modern pollen spectra an...
Organisms are extremely sensitive to many parameters of the physical environment, and their fossil remains may thus be used in the interpretation of ancient environments. Effective use of paleoecology depends on first determining what environmental parameters are of interest. Second, developing a model based on recent examples which can be tested on the fossil record, and third, testing the mod...
A new genus and species of fossil trachypachid Fortiseode pervalimand Jia & Ren gen. et sp. nov., is described and illustrated. The new fossil with large and strong mandibles, short and robust legs, and pronotum widest near apical angle differs from other members of Eodromeinae. It is the first record of fossil trachypachid from the Mesozoic Yixian Formation of Huangbanjigou, Liaoning, China.
Citation: Cosmidis J, Benzerara K, Guyot F, Skouri-Panet F, Duprat E, Férard C, Guigner J-M, Babonneau F and Coelho C (2015) Calcium-Phosphate Biomineralization Induced by Alkaline Phosphatase Activity in Escherichia coli: Localization, Kinetics, and Potential Signatures in the Fossil Record. Front. Earth Sci. 3:84. doi: 10.3389/feart.2015.00084 Calcium-Phosphate Biomineralization Induced by Al...
Two new fossil jawbones from Kenya are claimed to confirm a diversity of early Homo species. However, archaic species concepts and an inadequate fossil record continue to obscure the origins of our genus.
Uncertainty in divergence time estimation is frequently studied from many angles but rarely from the perspective of phylogenetic node age. If appropriate molecular models and fossil priors are used, a multi-locus, partitioned analysis is expected to equally minimize error in accuracy and precision across all nodes of a given phylogeny. In contrast, if available models fail to completely account...
The fossil record provides the only direct evidence of temporal trends in biodiversity over evolutionary timescales. Studies of biodiversity using the fossil record are, however, largely limited to discussions of taxonomic and/or morphological diversity. Behavioural and physiological traits that are likely to be under strong selection are largely obscured from the body fossil record. Similar pr...
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