In the “The Common Hand” (National Geographic, May, 2012), Carl Zimmer wrote that our hands began to evolve from fins at least 380 million years ago, and within 40 million years, held five fingers. Many animals have hands. Did hands emerge independently over, and over again, or did they evolve from a common ancestor? As Zimmer noted, “Darwin could recognize only the outward signs that hands had evolved from a common ancestor. Today scientists are uncovering the inward signs as well.”
These 3D illustrations of radiographic images by Bryan Christie, Joe Lertola, Jeong Suh, and Victoria Rompilla [check sequence with Erica] featured in the Zimmer article, show how much more difficult it was for Darwin to recognize the hand of the elephant, or aye-aye, or bat or than it is for us. The hand of the elephant is obscured by adaptations to withstand extreme weight. The hand of the aye-aye, a long fingered lemur, is capable of teasing out insect larvae hidden in recesses of trees. The thin- fingered hand of the bat (modeled here, on a flying fox) is adapted to stretch the mem- branous wing into flight-worthiness.
Science Art-Nature .presents:
