Extinct large colobines from the Plio-Pleistocene of Africa

Three genera and six species of extinct African Plio-Pleistocene Colobinae are discussed. One new genus, Rhinocolobus and three new species, R. turkanaensis, Cercopithecoides kimeui and Paracolobus mutiwa are named. These colobines show a diversity in postcranial and dental morphology not seen among extant species. Rhinocolobus was most similar to extant Colobus in postcranial morphology and had similar high-cusped shearing teeth. Cercopithecoides shows a number of postcranial skeletal features typical of terrestrial cercopithecid species and has lower cusped teeth. Paracolobus, while generally more similar to Rhinocolobus than to Cercopithecoides, is intermediate in some features of its postcranial morphology. The distribution of the various taxa among East and South African sites with different palaeoenvironments is generally consistent with the morphological interpretation. With the exception of Cercopithecoides kimeui, which persisted a little longer, these large colobines disappear from the fossil record about 1.8 million years ago. Their disappearance coincides with an interval of increasing aridity documented at Olduvai Gorge, the Omo Valley, and East Turkana.     

鸟类中的猎食者

鸟类的掠食者偶有看似凶残的。却是为了基本的生存。自然界的生命,有掠食者,也有被食者．它们都在维系自然的平衡．捍卫自然的法则。在动物世界中的掠食者只缘于符合自然规律的本能存在．却没有像人类这样贪婪的真正的掠食者。     

Watching Birds

[Watching Birds. By James Fisher. Pelican Books: published by Penguin Books, Hardmondsworth, Middlesex, England, 1940; reprinted 1941.]     

Genomes of Pleistocene Siberian Wolves Uncover Multiple Extinct Wolf Lineages

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Extinct mammalian biodiversity of the ancient New World tropics

The origins of mammalian biodiversity in the New World tropics extend back >25 million years, represented by clades that were originally endemic to South America, North America or Africa. Since then, these mammalian clades have been greatly affected by climatic, physiographic and biological changes. The Isthmian land bridge, which formed approximately 4 million years ago between North and South America, resulted in the maximum diversity of 17 New World tropical mammalian orders during the Great American Interchange. This diversity was subsequently reduced to 12 orders as a result of competition, climate change and human impacts. Here, I discuss how the fossil record is now providing a rich archive of past biodiversity, presenting unique evidence of the origins, macroevolution, macro-ecology and extinction of New World tropical mammals.     

Thermogenesis in Birds

The article discusses the importance of avian skeletal muscle as a source for heat generation by means of both shivering and non-shivering. Non-shivering thermogenesis in birds is still a polemic issue. Recent evidence at the molecular/cellular level indicates, however, that this type of heat generation may also exist among birds. The involvement of the sarcoplasmic reticulum calcium ATPase in non-shivering thermogenesis is discussed in-depth.     

被视为恐龙的鸟

尽管于 2 0世纪 2 0年代在亚洲地表层首次发现长有羽毛的恐龙和著名的“龙骨突位点” ,关于鸟类起源的争论仍没有休止。来自化石的证据表明 ,鸟类在进化分支上应归于兽脚类的特殊分支。本文主要阐明完好无损的化石揭示的鸟和非鸟类恐龙的亲密关系和鸟类羽毛及鸟类出现以前的羽毛的起源证据 ,分析体型缩小对飞行进化的重要意义及从新的角度论述鸟类如何飞上了天