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.

“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 ...

How fast does the beak move? To answer these questions, I’m recording high-speed X-ray videos of the feeding birds. Interestingly, I discovered some fascinating differences in beak movement ...