Although its beak is quick sharp, the bird sometimes dies choking on prey that’s too big for its throat. While long and wide ...

“normal” beaks (examples shown of a petrel and a gull) and a bird with a tactile bill-tip organ (a tinamou, close relative of ostriches and emus and which has an ancestral bill-tip organ ...

Smaller finches with less-powerful beaks perished. So the birds that were the winners in the game of natural selection lived to reproduce. The big-beaked finches just happened to be the ones ...