Fish Gave Us the Finger

Fingers are pretty nifty. They let you to grab a latte, type on a keyboard, even pull up your pants. But did you ever wonder: where do fingers come from? In the 1990s, scientists gave this problem a lot of thought. And they concluded that fingers were pretty much invented by the first tetrapods: that is, critters with four limbs. One reason they thought that is because a fossilized skeleton of an ancient fish didn’t appear to have any fingers. Or at least any distinct digits in its pectoral fin. But tetrapods, which evolved from fish, did.

Now scientists writing in the September 21st online issue of Nature say that that thinking was…a little fishy. Because they’ve unearthed evidence that suggests that that ancient fish did indeed have fingers in its fins. The researchers did a CT scan on a specimen about 380 million years old. And they found that the fish’s right fin, which was unusually well-preserved, does appear to have digitlike bones. The reason other researchers previously missed them, they think, is because in their samples the fingers were hidden behind marks left by the fish’s scales. So fish, too, seem to have incipient fingers. A finding we give two thumbs up.

人的手指由鱼类进化而来？

手指非常灵活。你喝带牛奶的咖啡时候要用它，打键盘要用它，甚至提裤子的时候也少不了手指的帮忙。但是你是否曾经想过：手指从哪里进化而来？在90年代，科学家们对个问题进行了许多思考。他们得出的结论是，手指很可能是从第一批四足动物那里“发明”出来的。这些科学家这样思考的一个理由是因为从一只古代鱼的化石骨骼上没有发现任何的手指，至少是在这只鱼的胸鳍里没有发现明显的手指。但是从鱼类进化而来的四足动物却有手指。

但是现在科学家们在9月21日的《自然》(Nature) 杂志上报道说上述的观点有些问题。因为他们发现了新的证据，这些证据表明那只古代鱼确实在它的鳍里面存在手指。研究者们对一个3.8亿年前的生物标本进行了CT扫描。他们发现这只鱼的不同寻常地保留下来的右鳍的确看起来具有手指一般的骨头。这些科学家们认为以前的科学家们没有发现这个的原因在于在以前科学家使用的样本中，鱼的手指被鱼的鱼鳞留下的痕迹所掩盖。所以，看起来鱼也有未成型的手指。对这个发现我们竖起两个大拇指赞成。

Vocabulary:
Nifty: 灵活
Grab: 抓住
Latte: 带牛奶的咖啡
Tetrapod: 四足动物
Critter: （口语）动物
Limb: 四肢
Digit: 手指
Pectoral: 胸部的
Fishy: 可疑的
Unearth: 挖掘
Specimen: 样本
Incipient: 初始的