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记述了发现于内蒙古苏崩晚古新世格沙头期的中兽类软食中兽Hapalodectes属的一个新种。这是软食中兽在中国古新世地层中的首次发现,也是亚洲格沙头期的第二种软食中兽。已有的系统学和生物地层学证据支持软食中兽属和软食中兽科(Hapalodectidae)亚洲起源的观点。软食中兽显然是在古新世-始新世极热事件(PETM)期间通过白令陆桥扩散到北美大陆的,因而符合“东方伊甸园”学说中的生物地理格局。软食中兽有限的(即非欧洲的)地理分布使得我们可以重建该属生物地理学历史。如同软食中兽一样的“东方伊甸园”式的扩散模式,可以看作是大的环境变化事件导致多个支系产生相似的系统学和生物地理学分布格局的生物地理扩散机制。严格地检查了所谓的在古新世-始新世界线上或其附近的与“东方伊甸园”模式相矛盾的大陆间哺乳动物扩散事例,结果发现这些例子都是不可靠的。“东方伊甸园”生物地理学说充分解释了PETM时期哺乳动物群更替以及劳亚古陆哺乳动物地理分布格局的成因。
Describes a new species of Hapalodectes genus found in the soft-diet foraging of the mid-mammals in the early Neocene period of the Soviet Union, Inner Mongolia. This is the first discovery of the soft-shelled beast in the Paleozoic strata in China and is also the second soft-shelled animal in the Gesha head period in Asia. Available systematic and biostratigraphic evidence supports the notion of Asian origin in the genus Hapalodectidae in soft foods. The soft-shelled beast has apparently spread to the North American continent through the Bering Land Bridge during the Pliocene-Eocene Extreme Event (PETM), and thus conforms to the biogeographical pattern in the “Oriental Garden of Eden” doctrine. The limited distribution of soft beasts (ie non-European) allows us to reconstruct the history of biogeography. As with the soft-shelled beast, the “Oriental Garden of Eden” pattern of diffusion can be viewed as a mechanism of biogeographical proliferation that leads to similar systems of genetics and biogeography distribution across multiple branches due to large environmental change events. Strict examination of the so-called case of mammal spread between continents on or near the Pliocene-Eocene line contradicting the “Oriental Garden of Eden” has found these examples to be unreliable. “Oriental Garden of Eden ” biogeography theory fully explained the evolution of mammals during the PETM period and the genesis of the geographical distribution pattern of the mammals in the Laurasian.