No mammal except man has more abundant cerebral matter.

任何哺乳类都没有这样丰髓神经。

In come amphibians, reptiles, dinosaurs and finally, mammals.

接下来就是会出现两栖物，爬行物，恐龙，最后是哺乳类物。

Right next door is a very different kind of gallery. At the La Brea Tar Pits and George C. Page Museum, remains of incredibly preserved mammals, insects and plants are continually excavated and brought once more into the Californian sunshine.

博物馆旁边有着风格截然不同展览馆。拉布雷亚沥青坑和佐治佩奇博物馆拥有保存极为良好哺乳类物、昆虫和植物。一直以来，考古学家都不断在这里挖掘出植物遗迹，使牠们重现于世。

In fact, sloths use about 90 percent less energy than the average mammal, which is vital, considering their diet is a low-energy snack consisting of leaves...with a side of leaves.

事实上，树懒所消耗能量只有一般哺乳类百分之十，这很重要，考虑到它们主食简直就是低热量心，除了树叶...还是树叶。

But some scientists think mammals also have this capability.

但有些科学家认为哺乳类物也有这种能力。

But for a variety of reasons, it's difficult to do the kinds of experimental studies in an animal like an orca, or many of these other large mammals, that might elucidate those kinds of questions.

但基于许多理由，很难针对像虎鲸或许多其他大型哺乳类物进行实验研究，因此无法解答这类问题。

And as they get older they transition to feeding more on mammals.

当它们越来越大，就要转为喂它们较多哺乳类。

In most mammals, the placenta is confined behind a barrier of maternal cells.

大多数哺乳类物胎盘 被母亲体内一层屏障围着。

Some se aplants, like seaweed, are also used as food. Animals in the sea range from tiny one-celled animals to huge mammals.

一些海洋植物，像海藻也经常作为食物。 海洋物种类很广泛，从单物到巨大哺乳类物。

Exactly why robber crabs have grown so big is a mystery, but with so few creatures making it to these remote islands, the giant crustaceans seem to have filled a niche normally taken by medium-sized mammals.

到底为什么盗蟹长得如此之大是个谜团，但是因为只有极少数生物才能到达这些偏远岛屿，所以这大甲壳纲物似乎填补了通常由中型哺乳类物占据生态位。

Killing mammals was either just collateral damage or a form of protection against possible predators.

杀死哺乳类物要么只是一种附带损伤，要么是一种防御潜在捕食者形式。

It's a tree-dwelling mammal about the size of a raccoon that's native to Southeast Asia.

这种产于东南亚地区在树上生活哺乳类物，体型和浣熊相当。

You find it associated with play, and all mammals play.

你会发现笑是在玩耍中发生， 而所有哺乳类物都会玩耍。

The last group of animals we are going to talk about is mammals.

我们将要讲最后一群物是哺乳类。

It's only been shown to apply to non-aquatic mammals.

目前只证明它适用於 非水生哺乳类物。

Because mammalian predators that stay below that number can exist on prey smaller than them.

因为体重在20公斤以下哺乳类物能以追捕体型较小猎物为生。

Earlier in his career he undertook an identical task, except he wrote about predicting the possibility of mammals being rediscovered on mars and was knighted at the royal castle by the elder emperor for his achievement.

在他职业生涯早期，他就从事着相同工作。除此之外，写了一篇关于预测火星上可能再次发现哺乳类物文章。由于他成就，他被皇家城堡老皇帝封为爵士。

Of mammals only humans and some primates enjoy color vision. The red flag is black to the bull. Horses live in a monochrome world .

在哺乳类物中，只有人和一些灵长目物能够分辨颜色。红旗在公牛看来是黑色，马则生活在一个单色世界里。

Now, a new study of wild mammals has found great differences in length of life and aging in many species of mammals.

现在，一项关于野生哺乳物新研究发现，许多哺乳类物寿命和衰老都存在巨大差异。

The advanced mammalian brain of the Brygmophyseter enables it to listen for a distress call while still engaged in hunting.

四贺鲸先进哺乳类大，使之能够在捕猎同时收听到这一遇难呼号。