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DescriptionScience Magazine - 15 May 2015 {Bindaredundat}   How birds got their beaks Combining fossils and lab studies, researchers home in on genes that transformed a snout into a bill.  Ground-dwelling birds build complex nests Living on the ground floor isn’t always a bargain—at least when it comes to a bird’s nest. A nest can be anything from a few twigs thrown together on a flat space to an elaborately woven hanging orb—but in one family of birds, those species that live lower down tend to build more elaborate nests, scientists report this week in The Auk: Ornithological Advances. Although a simple cup-shaped nest suffices for this bearded parrotbill (shown), which lives a meter high among cobweb-laden grass stalks, the parrotbill’s ground-based relatives build more elaborate dome-shaped lairs to keep predators away from their young. To understand why birds have such different housing tastes, neurobiologist Zachary Hall of the University of Toronto analyzed nest placement and type across the family tree of 90 species of Old World babblers like the parrotbill. In previous work, Hall had helped establish that birds with more complex nests have more folds in the cerebellum, a part of the motor control section of the brain. Now, he and his colleagues report that for these birds, the more complex domed nests coevolved with the move to the ground.  IN FROM THE COLD After keeping science alive during decades of scarcity, Cuba’s “guerrilla scientists” are ready to rejoin the world By Richard Stone, in Havana.  Related Torrents
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