Allotheria
| Allotheria | ||||||||||||
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Skull of Meniscoessus |
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| Temporal occurrence | ||||||||||||
| Upper Triassic to Eocene | ||||||||||||
| 235 to 40 million years | ||||||||||||
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| Scientific name | ||||||||||||
| Allotheria | ||||||||||||
| Marsh , 1880 | ||||||||||||
The Allotheria are a taxon (a systematic group) of extinct mammals . It summarizes three groups:
- the Haramiyida , who lived in the Triassic and Jurassic and are among the oldest known mammals,
- the Multituberculata , a species-rich group that lived in the continents of the northern hemisphere from the Jurassic to the Eocene and
- the Gondwanatheria , which occurred in the southern continents from the Upper Cretaceous to the Eocene.
The suspected relationship is based on the structure of the molars , which are characterized in all three groups by a conspicuous arrangement of the cusps. A possible scenario sees the ancestors of the other two groups in the Haramiyida, which spread in the Mesozoic and early Cenozoic but were later ousted by modern mammals.
The research was made more difficult by the fact that for a long time hardly any fossils were known of the Haramiyida and the Gondwanatheria apart from a few teeth. In the meantime, however, jaw parts have also been discovered by both groups, as well as the skull of a genus of Gondwanatherien and well-preserved, almost complete fossils of various tree-dwelling Haramiyids. The Haramiyida, which have turned out to be paraphyletic and consist of some basal genera and the tree-dwelling Euharamiyida, have a very primitive jaw structure, while the jaw of the Multituberculata and Gondwanatheria is more similar to that of today's mammals.
Detailed cladistic analyzes show clearly that the allotheria a monophyletic group and are composed of the above three groups. The following cladogram according to Krause et al. shows the position of the Allotheria within mammals and their internal systematics:
| Mammals |
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Individual evidence
- ^ Thomas S. Kemp: The Origin & Evolution of Mammals . Oxford University Press, Oxford 2005, 331 pages, ISBN 0-19-850761-5
- ↑ a b c David W. Krause, Simone Hoffmann, John R. Wible, E. Christopher Kirk, Julia A. Schultz, Wighart von Koenigswald, Joseph R. Groenke, James B. Rossie, Patrick M. O'Connor, Erik R Seiffert, Elizabeth R. Dumont, Waymon L. Holloway, Raymond R. Rogers, Lydia J. Rahantarisoa, Addison D. Kemp, Haingoson Andriamialison. First cranial remains of a gondwanatherian mammal reveal remarkable mosaicism. Nature , 2014; DOI: 10.1038 / nature13922
- ↑ a b c Shundong Bi, Yuanqing Wang, Jian Guan, Xia Sheng, Jin Meng. Three new Jurassic euharamiyidan species reinforce early divergence of mammals. Nature, 2014; DOI: 10.1038 / nature13718
