【一分钟科普】古人类一生都保持婴儿时期的智力水平

CT scans reveal that the brains of Neandertal babies had the same elongated shape as those of modern human babies. But whereas modern humans' brains become rounder as they mature, Neandertals retained the elongated shape throughout their lives. Karen Hopkin reports
CT扫描显示，尼安德特（古人类）婴儿的大脑是修长形状的，这和现代人类婴儿的大脑没什么两样。可是当今婴儿长大后大脑就会变圆，而尼安德特人整个一生大脑都是保持着婴儿时的状态。  Karen Hopkin 报道
（译者注：中文名称：尼安德特人 英文名称：Neanderthal        定义：距今大约20万~3万年生活在欧洲、近东和中亚地区的古人类。尼安德特人已经能够制造使用复合工具、具有狩猎能力及丧葬等习俗。对尼安德特人的分类地位有不同看法，有学者将其归入一个人属内与智人并列的尼安德特种，也有学者将尼安德特人归入古老型智人。3万多年前，随着冰川蔓延过整个欧洲大陆，尼安德特人便灭绝了。 ——来自百度百科）
Modern human babies are essentially learning machines. After birth, their brains grow in leaps and bounds, allowing infants to lay the groundwork for future social and cognitive achievement. But it wasn’t that way for Neandertals. At least in terms of the shape of their brains, Neandertal newborns pretty much coasted into adulthood. 现代的婴儿基本上将来都会学习使用机械。小宝贝们出生以后大脑就非常迅速地发育，为将来这些婴幼儿能完成社会认知做着准备。可惜，尼安德特人没这样的发育过程（只长肉不长脑子）。至少就他们大脑的形状而言，尼安德特新生婴儿的大脑与他们成人时的几乎差不多。
Scientists have shown that Neandertal brains are about the same size as ours. Yet our Paleolithic brethren are not known for having been great scholars. To probe this cognitive conundrum, researchers took CT scans of 11 Neandertal brains, including one newborn. And they compared these images to those of modern humans. 科学家们发现尼安德特人与我们现代人大脑的尺寸差不了多少。然而，在我们旧石器时代的同胞们里，还没听说过有几个伟大学者产生过。为了证明这个在认知方面的问题，研究者对11个尼安德特人进行了CT扫描，这11个人里头包括一名新生儿。并将形成的图像与现代人的进行了对比。
They found that baby braincases are similar in size and shape, regardless of their parentage. All are elongated, 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 neural development. That phase change is absent in Neandertals, 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 spiffy in a cap and gown. —Karen Hopkin他们发现不管父母是谁，婴儿之间脑壳的尺寸、形状非常相似，其都是狭长形状的。对于这点，最有可能的解释就是他们在出生的时候极其顺利。但是现在的婴儿们的大脑，在他们出生后第一年会越长越圆，这种改变反应了人类神经学的巨大进步。但是尼安德特人缺乏这一时期的进化，在今后的一生中他们的大脑仍然保持着出生时的形状。研究结果刊登在《当代生物学》期刊上。目前还不清楚，是否是我们圆圆的脑袋造就了今天这具有极高智商的人类。但它们确实让我们在穿着毕业礼服的时候好看点。
——Karen Hopkin报道