SSS 2008-06-27(在线收听

This is Scientific American's 60-Second Science, I am Cynthia Graber. This'll just take a minute.

For the last five years, researchers have been analyzing bird DNA. That effort has now completely altered our understanding of which bird species really do flock together in evolutionary history. The overall project is called Assembling the Tree of Life, with the avian part known as Early Bird. The new relationships appear in the June 27th issue of the journal Science. It turns out much of what we thought about how bird species were related to one another was just wrong. For example, scientists thought that birds that live on water, like flamingos, evolved from a separate waterbird group. But flamingoes took to the water after speciating. And it might make sense to think that birds with similar lifestyles, like falcons and eagles, were related. Nope. Instead, falcons are more closely related to parrots. Rearchers found other surprising relatives—colorful hummingbirds that flit about when the sun shines descended from drab, nocturnal nightjars. Get ready for Latin species names to change. And textbooks and field guides will have to be revised to correct former assumptions about relationships. The 82 million American birdwatchers will certainly go cookoo.

 

Thanks for the minute for Scientific American's 60-Second Science, and I'm Cynthia Graber.

 

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