2021年经济学人 恐龙曾“落户”北极(2)（在线收听）

Until now, no such hatchlings had been found, and the only known polar dinosaur eggs were from the Kakanaut formation of north-eastern Russia, which was only just within the Arctic Circle when its rocks were laid down.

到目前为止，还没有发现这样的小恐龙，唯一已知的极地恐龙蛋来自俄罗斯东北部的Kakanaut地层，当岩石被埋下时，该地层刚好位于北极圈内。

Dr Druckenmiller's discoveries are from the Prince Creek Formation of northern Alaska, which may have been as close as 5° of latitude from the North Pole when its rocks formed 70m years ago.

德鲁肯米勒博士的发现来自阿拉斯加北部的普林斯克里克地层，那里的岩石在形成于7000万年前时可能距离北极的纬度只有5°。

The fossils themselves come from a range of dinosaur groups, including ceratopsians (related to the likes of Triceratops), duck-billed hadrosaurs, large carnivores related to Tyrannosaurus and smaller velociraptor-like predators.

这些化石本身来自一系列的恐龙群，包括角鼻龙(与三角龙之类的恐龙有亲缘关系)、鸭嘴龙、与霸王龙有亲缘关系的大型食肉动物以及小型的类似迅猛龙的食肉动物，

This suggests a diverse and flourishing ecosystem, despite the fact that Prince Creek was continuously dark for 120 days a year and had an average annual temperature of 6°C—meaning snow would have been common in winter.

展现了一个多样化的、繁荣的生态系统，尽管普林斯溪一年中有120天一直处于黑暗之中，而且年平均温度为6°C——这意味着冬季降雪频繁。

How all these creatures survived those conditions was, Dr Druckenmiller suggests, a consequence of dinosaurs' warmbloodedness and the downy feathers many of them are now known to have sported.

德鲁肯米勒博士认为，所有这些生物之所以能在这样的环境中生存下来，是因为恐龙是温血动物，而且现在我们知道，恐龙中有许多都长有蓬松的羽毛。

No direct evidence of feathers has yet been found among the Alaskan fossils, but their ubiquity elsewhere makes it likely they had them.

虽然目前在阿拉斯加化石中还没有发现羽毛的直接证据，但它们在其他地方的普遍存在使得它们有可能长有羽毛。