The bear case rests on patience, a Persian restoration and a Permian boom.

看跌理由在于耐心，波斯恢复和二叠繁荣。

The idea that an impact caused the Permian extinction has been around for a while.

导致二叠大灭绝原因长期以来都没有一个定论。

But as the Permian went on, the climate got hotter and drier.

但随着二叠行，气候变得越来越 热和干燥。

The acquisition expands Chevron's shale-oil assets in America's Permian basin, where Anadarko is a leading independent operator.

此次收购扩大了雪佛龙在美国二叠盆地页岩油资产，阿纳达科是该地区领先独立运营商。

Presto! The Permian mass extinction is explained.

就这样！这就是二叠物种大灭绝解。

The event took place at the end of what Earth scientists, or geologists, call the Permian Period.

这一事件发生在地球科学家或地质学家所说二叠末期。

And as it turned out, the Permian too was absolutely covered with previously inaccessible petroleum-rich shale rocks beneath the surface.

而事实证明，二叠盆地地表下也绝对覆盖着以前无法触及富含石油页岩。

And then all eyes began once again turning back towards the gigantic Permian Basin over in west Texas.

然后，所有目光转向德克萨斯州西部巨大二叠盆地。

We think something similar was the cause of the end-Permian extinction.

我们认为类似事情是二叠末灭绝原因。

As the Permian progressed, amniote predators like Dimetrodon, Ophiacodon, and eventually saber-toothed gorgonopsians became widespread.

随着二叠展，羊膜动物捕食者如异齿龙、蛇夫和最终剑齿蛇目动物变得普遍。

The cause of the End-Triassic extinction is even murkier than the End-Permian extinction.

三叠末灭绝原因甚至比二叠末灭绝原因还要模糊。

First was the Permian-Triassic extinction 252 million years ago -- aka the Great Dying.

首先是 2.52 亿年前二叠-三叠大灭绝 ——也就是大灭绝。

With unique teeth, extra speed, and a complex social life, Dimetrodon was able to dominate Early Permian environments.

凭借独特牙齿、超快速度和复杂社会生活，异齿龙能够主宰二叠早期环境。

Another major player in Permian waters was Prionosuchus, a genus from Brazil.

二叠水域另一个主要参与者是来自巴西Prionosuchus。

This includes what's probably the Permian's most famous amphibian: Eryops, found in Texas and the southwestern United States.

这包括可能是二叠最著名两栖动物：Eryops，发现于德克萨斯州和美国西南部。

Marathon owns assets in Eagle Ford in Texas, Bakken in North Dakota, Permian in New Mexico and Texas, and in Oklahoma.

马拉松石油公司在德克萨斯州鹰滩、北达科他州巴肯、新墨西哥州和德克萨斯州二叠盆地以及俄克拉荷马州拥有资产。

But in the Early Permian, humid tropical swamps still straddled the equator.

但在二叠早期，潮湿热带沼泽仍然横跨赤道。

Estimates for the number of animal species alive at the end of the Permian range from as low as 45,000 to as high as 240,000.

据估计，二叠结束时候，活着动物物种数量从45000-240000种不等。

But the real whopper was the Permian extinction of about 245 million years ago, which raised the curtain on the long age of the dinosaurs.

但是，真正厉害是大约24500万年前二叠灭绝，它为漫长恐龙时代揭了序幕。

But evidence is accumulating that the biggest extinction of all, 252.3m years back, at the end of the Permian period, was indeed also triggered by an impact.

不过有证据不断地证明发生在2亿5230万年前二叠时期那次大灭绝也是因为陨石坠落而造成。