A recent study says fossil remains of a top meat-eating animal living 250 million years ago, which had only been found in the world’s northern half, also lived in South Africa. The scientists all have links to South Africa. They reported on fossils of a large ancestor to today’s mammals called Inostrancevia. The creature had only been known from fossils found in Russia near the Artic Sea until the new fossils were discovered at a farm in central South Africa. The fossils suggest that Inostrancevia left its native area and moved about 12,000 kilometers over a period of hundreds or thousands of years. During that period, most of the world’s big landmasses were connected in what scientists call Pangea.

最近的一项研究表明，生活在 2.5 亿年前的顶级食肉动物的化石遗骸也生活在南非，这种动物仅在世界北半部发现过。这些科学家都与南非有联系。他们报告了今天哺乳动物的大型祖先的化石，称为 Inostrancevia。直到在南非中部的一个农场发现新化石之前，人们只是从俄罗斯靠近北冰洋的化石中才知道这种生物。化石表明，Inostrancevia 离开了它的原生区域，并在数百或数千年的时间里移动了大约 12,000 公里。在那段时期，世界上大部分的大陆地都连接在科学家们称之为盘古大陆的地方。

Inostrancevia filled the ecological place of a top meat-eating animal in South Africa that had been missing after four other species had died out. "However, it did not survive there long," said Christian Kammerer. He is a scientist with the North Carolina Museum of Natural Sciences. Kammerer studies fossils and was the lead writer of the research published in Current Biology. "They have no living descendants, but they are a member of the larger group called synapsids, which includes mammals as living representatives," Kammerer added. Kammerer noted that Inostrancevia and all of its closest relatives disappeared in the mass extinction called "the Great Dying." The event took place at the end of what Earth scientists, or geologists, call the Permian Period.

Inostrancevia 填补了南非一种顶级食肉动物的生态空间，这种动物在其他四种物种灭绝后就消失了。 “然而，它并没有在那里存活太久，”Christian Kammerer 说。他是北卡罗来纳自然科学博物馆的科学家。 Kammerer 研究化石，并且是发表在《当代生物学》(Current Biology) 上的研究的主要作者。 “它们没有现存的后代，但它们是更大的突触类群的成员，其中包括哺乳动物作为现存代表，”Kammerer 补充道。 Kammerer 指出，Inostrancevia 及其所有近亲都在被称为“大灭绝”的大规模灭绝中消失了。该事件发生在地球科学家或地质学家所说的二叠纪末期。

Scientists believe that life on Earth was under pressure about 250 million years ago. Some scientists say volcanic activity in today’s Russian area called Siberia warmed Earth temperatures. It caused up to 90 percent of species to die out. Inostrancevia is part of a group of animals called protomammals that combined reptile-like and mammal-like features. It was three to four meters long and had a large, long head with a set of huge teeth it used to kill and eat other animals. If the animals were small enough, Inostrancevia swallowed them whole. Inostrancevia was structured differently from both reptiles and mammals but was usual for protomammals. It carried itself in a way that was neither flat to the ground like reptiles nor standing tall like mammals. It also lacked facial muscles found in mammals and did not produce milk.

科学家认为，地球上的生命在大约 2.5 亿年前就处于压力之下。一些科学家说，今天俄罗斯称为西伯利亚的地区的火山活动使地球温度升高。它导致高达 90% 的物种灭绝。 Inostrancevia 是一组称为原始哺乳动物的动物的一部分，它们结合了爬行动物和哺乳动物的特征。它身长三四米，长着一个又大又长的脑袋，上面长着一排巨大的牙齿，用来杀死和吃掉其他动物。如果这些动物足够小，Inostrancevia 就会将它们整个吞下。 Inostrancevia 的结构不同于爬行动物和哺乳动物，但通常用于原始哺乳动物。它的行走方式既不像爬行动物那样平放在地上，也不像哺乳动物那样直立。它还缺乏哺乳动物的面部肌肉，并且不产奶。

"Whether these animals were furry or not remains an open question," Kammerer said. The mass extinction happened over about one million years. It led to the rise of dinosaurs during the following Triassic Period. The scientists noted that top meat-eating animals are especially affected by extinction because they require the most food and space. The researchers said they see similarities between the Permian mass extinction and today’s climate change problem.

“这些动物是否有毛茸茸仍然是一个悬而未决的问题，”Kammerer 说。大灭绝发生了大约一百万年。它导致了随后的三叠纪时期恐龙的兴起。科学家指出，顶级食肉动物尤其容易受到灭绝的影响，因为它们需要最多的食物和空间。研究人员表示，他们看到了二叠纪大灭绝与当今气候变化问题之间的相似之处。

Pia Viglietti is with the Field Museum in Chicago. She helped write the study. She said unlike the animals that came before us during the Permian Period, “we actually have the ability to do something to prevent this kind of ecosystem crisis from happening again.”

Pia Viglietti 在芝加哥的菲尔德博物馆工作。她帮助撰写了这项研究。她说，与二叠纪时期出现在我们面前的动物不同，“我们实际上有能力做一些事情来防止这种生态系统危机再次发生。”