Photo by Mark Olsen[/caption] The most common shape for typical seed-eating birds is a short, thick, and conical beak. Think of the classic "triangle" shape. This strong, sturdy beak acts like a ...

Under these drastically changing conditions, the struggle to survive favored the larger birds with deep, strong beaks for opening the hard seeds. Smaller finches with less-powerful beaks perished.

For example, the cactus finch has a long beak that reaches into blossoms, the ground finch has a short beak adapted for eating seeds buried under the soil, and the tree finch has a parrot-shaped ...

Caption Darwin noted how different finches from the Galapagos Island developed different kinds of beaks, based on the food that they specialized in eating. Later studies showed how rapid ...

The different finch species on the islands are closely related to each other, but show wide variations in beak and body size and feeding behaviour. In particular, changes to the size and shape of the ...

They consult genetic scripture. Consider, for instance, the famous finches of the Galápagos. Darwin could see that their beaks were variously shaped—some broad and deep, others elongated ...