首页 > 娱乐资讯 > 开心乐园 > 英语短文欣赏:Scientific American

英语短文欣赏:Scientific American

来源:潮女谷    阅读: 3.01W 次
字号:

用手机扫描二维码 在手机上继续观看

手机查看

Forty-six million years ago, northwest Montana was a tropical forest of giant ferns, conifers and ginkgos. Tiny primates lived there, as did rhinos and horses and crocs. Along with some less charismatic creatures: mosquitoes.

英语短文欣赏:Scientific American

One of those millions of mosquitoes was then blown onto the surface of an ancient lake. Unable to lift off, it eventually sank to the bottom. And became a fossil.

The fossil mosquito was recently found. And analyzed. Scientists found that its belly contained iron, bound up in a molecule called heme—the compound in blood that carries oxygen. So it appears this sucker died and fossilized with a bellyful of blood—the only known specimen. The findings appear in the Proceedings of the National Academy of Sciences. [Dale E. Greenwalt et al., Hemoglobin-derived porphyrins preserved in a Middle Eocene blood-engorged mosquito]

Now I know what you're thinking. "This fossilized tree sap waited for millions of years, with the mosquito inside. Until Jurassic Park scientists came along."

Well, not quite. DNA breaks down too quickly. And this skeeter lived 20 million years after dinos went extinct. Though researchers say it may have dined on birds--which are, in some sense, blood relatives.

—Christopher Intagliata

时尚热点
影视动漫
娱乐小料
明星动态
电影电视
音乐空间
开心乐园

最新文章