For Biologists, a New Understanding of Birds and the Tree of Life
Scientists analyzed the genomes of nearly 200 species of birds.
Earth is home to thousands of different species of birds with an amazing array of behaviors, body types, and colors. For biologists studying evolution, that diversity has presented a fundamental question: How did so many different types of birds evolve? And how do they relate?
That cardinal in your garden actually evolved from a hawk-like ancestor. And those hummingbirds and swifts you see buzzing around during the day? They actually "evolved from within a nocturnal group of insect eaters," said Richard Prum, an ecologist and evolutionary biologist at Yale.
Prum's talking about "neoaves" or so-called "new birds" that make up about 90 percent of the birds in existence. They're "new," in part, because they evolved so quickly, over the course of only a few million years.
That rapid evolution meant mapping these birds on a "tree of life" was hard. But now, thanks to a new genetic analysis led by Prum that was just published in Nature, he said scientists understand those relationships more clearly.
For example, "we found that almost all of the water birds are actually together in one group on the tree. That is, related to one another," said Prum. "Once they became associated with aquatic ecology, they pretty much stayed that way. Further, other birds didn't frequently evolve into that zone."
In his analysis, Prum and his co-authors analyzed the genomes of nearly 200 species of birds, looking at conserved regions of the genome and then sequencing outside spots that were more varied species-to-species.
Prum said this analysis provides a "backbone" for better understanding evolution in a well-studied species and the processes that give rise to animal diversity. The research is also packed with details for the 'bird nuts' out there, too.
"We found out that bustards are related to cuckoos -- right?" Prum said. "Which is a great thing for me, but not something that most people will find earth shattering."