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Wren Bones, Wren Bones

Another species of extinct, flightless New Zealand wren has been identified, suggesting the group may have been as diverse as the moas.

The wren, nicknamed the tree kiwi but unrelated to true kiwis, was about the size of a sparrow, with short, weak legs and a long, downcurved bill. Phil Millener, extinct bird biologist at the National Museum, says that ground-living wrens had long, strong legs, so this new species probably ran up and down the trunks of trees, probing in crevices for insects.

New Zealand wrens are quite different from their European namesake. Only two species --the rifleman and rock wren--survive today. The bush wren, once widespread, is presumed extinct like the flightless Stephens Island wren and two other ground wrens recently described from cave deposits by Millener. Birds, especially flightless ones often fall or are washed into caves.

With seven species known, and possibly more to be discovered, the New Zealand wren family may have been as diverse as the moas, and certainly boasted a greater range of body shapes and feeding habits. The widely held idea that New Zealand birds had not evolved extensively, remaining in a `primitive' ancestral state, now seems less well- founded.

Mike Dickison, National Museum