They might be giants, or dwarfs

Evolution often takes unexpected, and sometimes bizarre, directions on islands

By Beth Daley, Globe Staff | November 16, 2004

Their lives could have been the plot of a monster movie. Three-foot-tall humans recently discovered to have lived on an Indonesian island had to dodge giant lizards and rats the size of dogs. They were so tiny it appears they couldn't even overcome adult dwarf elephants, forced instead to hunt the animals' young.

But their adult size -- comparable to a modern 4-year-old -- had an upside, too, apparently allowing them to survive in isolation for tens of thousands of years. The existence of these little people, reported in the journal Nature last month, provides new scientific fodder for a mysterious evolutionary phenomenon that can radically shrink or balloon a species' size when it becomes isolated on islands.

"When species get to an island, you get evolution taking unexpected directions," said James H. Brown, distinguished professor of biology at the University of Mexico who has studied the phenomenon. "And some of it is bizarre."

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