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Dichodon (mammal)
''Dichodon'' is an extinct genus of Palaeogene artiodactyls belonging to the family Xiphodontidae. It was endemic to western Europe and lived from the middle Eocene up to the earliest Oligocene. The genus was first erected by the British naturalist Richard Owen in 1848 based on dental remains from the fossil beds in Hordle, England. He noticed similar dentitions to contemporary artiodactyls like those of the Anoplotheriidae and Dichobunidae and based the genus name off of ''Dichobune''. Eventually, it was found to be more closely related to ''Xiphodon'' and now composes of 11 species, although one of them may be synonymous. The xiphodontid had brachyodont (low-crowned) dentition, its premolars being elongated similar to other xiphodonts. However, it differs from them by the "molarization" of the fourth premolars, meaning that the top teeth appear quadrangular while the bottom ones appear more triangular. Its snout is also shorter and narrower compared to that of ''Xiphodon''. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope Carbon-13, 13C in the atmosphere was exceptionally low in comparison with the more common isotope Carbon-12, 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Popigai impact structure, Siberia and in what is now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
