甘肃发现一种史前猎豹新物种化石.

肯尼亚的猎豹.

研究人员在甘肃发现一种史前猎豹新物种化石，表明最古老的猎豹来自中国而不是北美。这是史前猎豹新物种的一个近完整的头骨，其大小和形状类似于现代猎豹的头骨。但它的一些牙齿特别原始，这表明这种学名为“Acinonyx kurteni”的中国猎豹处于猎豹进化史的早期阶段。其它形形色色的特征还表明其头骨相对其长度来说是一个大脑壳，还有加大的前窦。我国这一重大发现发表在12月30日出版的《美国国家科学院学报》上。

猎豹这种最快的陆地动物以112公里每小时的冲刺速度追捕猎物。据国际自然与自然资源保护联合会(IUCN)统计，目前估计全球的猎豹只有7500只，处于高度濒危的状态。非洲之外惟一已知的一种猎豹则更加濒危，仅仅在伊朗有100只左右。伊朗的猎豹是一种亚种。

其实，科学家发现的猎豹化石遍及非洲、欧洲、亚洲、印度次大陆(indian subcontinent)和北美，年代都在320万-2000年之间。此新发现的中国猎豹属于上新世晚期，为215万-255万年前。

先前发现的北美史前猎豹被科学家认为是欧洲古老巨型猎豹的近亲，从而让一些研究人员猜测最早的猎豹可能出自北美，之后穿越白令海峡，从阿拉斯加来到西伯利亚。但新发现挑战了这一猜测。

此发现还引发另一个挑战：一种理论认为现代猎豹和美洲狮共享同一祖先，但美洲狮的化石记录在美国只能追溯到40万左右。由于我国这一发现如此古老，为猎豹起源于亚洲提供了强有力的证据。我国中科院的科学家依据化石牙齿发现了另一种猎豹，学名为“Sivapanthera linxiaensis”。

推荐原始出处：

PNAS December 29, 2008, doi: 10.1073/pnas.0810435106

A primitive Late Pliocene cheetah, and evolution of the cheetah lineage

Per Christiansena,1 and Ji H. Mazákb

aZoological Museum, Universitetsparken 15, 2100 Copenhagen O, Denmark; and
bShanghai Science and Technology Museum, 260 Yan-an Road (East), Shanghai 200002, People's Republic of China

Abstract

The cheetah lineage is a group of large, slender, and long-limbed cats with a distinctive skull and dental morphology, of which only the extant cheetah (Acinonyx jubatus) is present today. The lineage is characterized by having abbreviated, tall, and domed crania, and a trenchant dentition with a much reduced, posteriorly placed protocone on the upper carnassial. In this article, we report on a new discovery of a Late Pliocene specimen from China with an estimated age of ≈2.2–2.5 million years, making it one of the oldest specimens known to date. A cladistic analysis confirmed that it is the most primitive cheetah known, and it shares a number of unambiguous derived cranial traits with the Acinonyx lineage, but has more primitive dentition than previously known cheetahs, demonstrating that the many unusual skull and dental characters hitherto considered characteristic of cheetahs evolved in a gradual fashion. Isolated teeth of primitive cheetahs may not be recognizable as such, but can be confused with, for instance, those of leopards or other similar-sized pantherine cats or pumas. The age and morphology of the new specimen supports an Old World origin of the cheetah lineage, not a New World one, as has been suggested. We name the new species Acinonyx kurteni in honor of the late Bj?rn Kurtén.