In birds' development, researchers find diversity by the peck

Cambridge, Mass. - September 24, 2012 - It has long been known that diversity of form and function in birds' specialized beaks is abundant. Charles Darwin famously studied the finches on the Galapagos Islands, tying the morphology (shape) of various species' beaks to the types of seeds they ate. In 2010, a team of Harvard biologists and applied mathematicians showed that Darwin's finches all actually shared the same developmental pathways, using the same gene products, controlling just size and curvature, to create 14 very different beaks.

Now, expanding that work to a less closely related group of birds, the Caribbean bullfinches, that same team at Harvard has uncovered something exciting—namely, that the molecular signals that produce those beak shapes show even more variation than is apparent on the surface. Not only can two very different beaks share the same developmental pathway, as in Darwin's finches, but two very different developmental pathways can produce exactly the same shaped beak.

Continued:  http://www.sciencecodex.com/in_birds_development_researchers_find_diversity_by_the_peck-98932