Although evolution of species is an established fact, palaeontologists occasionally come across what appears to be a dead end. Most evolutionary biologists seem to agree, based on fossil record, that the birds of today are direct descendants of dinosaurs, and that the first bird ancestors evolved some 150 million years ago. When birds got their wings, they lost the clawed fingers wielded by their dinosaur relatives. But they evolved agile beaks of all shapes and sizes, from the gulping gape of a pelican to the needle nose of a hummingbird that have enabled the 10,000 species of birds to thrive from the Arctic to the tropics, build intricate nests, and live on a wide range of foods - from the nectar of flowers to fruits, nuts, insects, and even small animals. But it was never established how birds got their beaks. Now we seem to have the answer. A team of researchers led by Bhart-Anjan Bhullar of Yale University and Arhat Abzhanov of Harvard University, who have been studying everything they could get their hands on about bird's beak formation and evolution, have identified two genes which may have been responsible for the transformation of the snout seen in some dinosaur species, including the present-day alligators, into bird beaks (Evolution, 12 May 2015 | DOI: 10.1111/evo.l2684).
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