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    This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute.

    Modern human babies are essentially¹ learning machines. After birth, their brains grow in leaps and bounds, allowing infants to lay the groundwork for future social and cognitive² achievement. But it wasn't that way for Neanderthals. At least in terms of the shape of their brains, Neanderthal newborns pretty much coasted into adulthood³.

    Scientists have shown that Neanderthal brains are about the same size as ours. Yet our Paleolithic brethren are not known for having been great scholars. To probe this cognitive conundrum⁴, researchers took CT scans of 11 Neanderthal brains, including one newborn. And they compared these images to those of modern humans.

    They found that baby braincases are similar in size and shape, regardless of their parentage. All are elongated⁵, most likely to smooth passage through the birth canal. But modern human baby brains grow more globular in the first year of life, changes that reflect a massive wave of neural⁶ development. That phase change is absent in Neanderthals, whose brains retain that extended newborn shape throughout their lives. The results appear in the journal Current Biology.

    It's not clear whether our well-rounded brains made us the pointy-headed intellectuals we are today. But they do make us look smart in a cap and gown.

    Thanks for the minute. For Scientific American's 60-Second Science, I'm Karen Hopkin.

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1 essentially
adv.本质上，实质上，基本上
参考例句：
Really great men are essentially modest.真正的伟人大都很谦虚。 She is an essentially selfish person.她本质上是个自私自利的人。

2 cognitive
adj.认知的，认识的，有感知的
参考例句：
As children grow older,their cognitive processes become sharper.孩子们越长越大，他们的认知过程变得更为敏锐。 The cognitive psychologist is like the tinker who wants to know how a clock works.认知心理学者倒很像一个需要通晓钟表如何运转的钟表修理匠。

3 adulthood
n.成年，成人期
参考例句：
Some infantile actions survive into adulthood.某些婴儿期的行为一直保持到成年期。 Few people nowadays are able to maintain friendships into adulthood.如今很少有人能将友谊维持到成年。

4 conundrum
n.谜语；难题
参考例句：
Let me give you some history about a conundrum.让我给你们一些关于谜题的历史。 Scientists had focused on two explanations to solve this conundrum.科学家已锁定两种解释来解开这个难题。

5 elongated
v.延长，加长( elongate的过去式和过去分词 )
参考例句：
Modigliani's women have strangely elongated faces. 莫迪里阿尼画中的妇女都长着奇长无比的脸。 A piece of rubber can be elongated by streching. 一块橡皮可以拉长。来自《用法词典》

6 neural
adj.神经的，神经系统的
参考例句：
The neural network can preferably solve the non- linear problem.利用神经网络建模可以较好地解决非线性问题。 The information transmission in neural system depends on neurotransmitters.信息传递的神经途径有赖于神经递质。