2017新托福听力解析:烹饪历史

　　Most large animals have to chew food extensively and form it into a mushy ball that’s easy to swallow. Cooking makes a huge difference—it softens the food and dramatically reduces eating time. Researchers calculated that if we lived like our non-cooking primate cousins, we’d spend about 48 percent of the day eating. But modern humans spend only about 5 percent of the day chowing down. So when our ancestors invented cooking, it gave them a major survival advantage.

　　So how long have ago did our forebears start barbecuing?

　　The softer food available via cooking allowed for the evolution of smaller molars and a smaller jaw. Researchers therefore compared the molars and body sizes of extinct hominids with modern humans and other primates. Turns out that Homo erectus and Neanderthals had, and modern humans have, molars that are smaller than would be predicted by looking at general primate evolution. The finding is in the Proceedings of the National Academy of Sciences. [Chris Organ et al, Phylogenetic rate shifts in feeding time during the evolution of Homo]

　　Based on the appearance of the smaller eating apparatus, the researchers infer that humanity discovered the benefits of cooking about 1.9 million years ago. And we’ve been enjoying the convenience, speed and taste benefits ever since.

　　—Cynthia Graber

　　人类的牙齿及下颚由于烹饪的发明而变得越来越小。目前发现的人类化石表示掌控火候的烹饪技术可以追溯到190万年前。Cynthia Graber报道。

　　大部分大型动物需频繁咀嚼食物使之变成糊状后以便于吞咽。而烹饪改变了这种情况-使食物能够变得更加容易消化，并且可以大量减少咀嚼的时间。研究人员指出如果我们像不会烹饪的灵长类同类一样生活，我们得每天花费48%的时间去吃东西，但是现在，我们只需要5%的时间。正是由于发明了烹饪技术才给我们的祖先带来了巨大的生存优势。

　　那么我们的祖先是什么时候开始开始烹调食物?

　　通过烹饪变得更加容易消化的的食物允许接受更小的牙齿和下颚，学者因此把现代人种中灭绝的人种还有一些灵长类动物得牙齿和体型做了比较，事实上，通过观察一般灵长类动物的演变过程，可以看出直立人，穴居人，还有现代人拥有的牙齿比预测的还要小。此结论摘要在国家科学院院士论文中。

　　研究者基于越来越小的进食用具的出现推断出人类发现烹饪的好处出现在190万年前。自此我们十分享受这方便，快捷和美味的过程。