New Zealand Tree Stuck in a Time Warp

A eucalyptus-like tree that grows in New Zealand is still defending itself from a giant bird that died out about 500 years ago. The lancewood tree changes its appearance twice in its lifetime — an adaptation, a new study suggests, that prevented it from being eaten by flightless moas. As a seedling, the lancewood tree (Pseudopanax crassifolius) sprouts small, brown, blotchy leaves. Then, as a sapling, its leaves grow into footlong spears with tiny barbs along the edge. Finally, the adult lancewood, which can reach a height of 20 meters, sports rounded, nondescript green leaves. Many scientists think that the tree evolved these metamorphoses to avoid moas, the main herbivores on the islands and a relative of emus and ostriches that humans hunted to extinction