Humans bear little resemblance to squirrels and even less to a bacterium that thrives in tins of irradiated horsemeat. But these and other far-flung creatures are offering new insights into the human condition. Although only a handful of organisms—notably fruit flies, nematodes and mice—have dominated comparative biology, scientists are casting a wider net for the biological lessons they say are lurking undiscovered in the wild. continued...

^BAT EMBRYO
Differences in when and how identical genes are expressed mean humans have fingers and bats have wings.

Photo: Scott Weatherbee, Niswander Lab

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Reprinted from the
HHMI Bulletin, September 2002, pages 28-32.
©2002 Howard Hughes Medical Institute