Breaking the ice on Antarctica

A RECENT find of fossils may help geologists break through the ice obscuring Antarctica's past. David Harwood of the University of Nebraska and his colleagues have collected fossils of marine molluscs, microscopic organisms and leaves and twigs, all from the Eocene period of 35 to 55 million years ago (Science, Vol 259, No 5101).

One remarkable find is a well-preserved piece of wood -- neither petrified or fossilised, as is the case with most finds -- embedded in rock. If scientists are able to isolate its DNA -- the blueprint of life -- it would provide clues to the evolution of plant life in Antarctica.

Harwood says the fossils also could resolve the long-running debate over when the frozen continent was taken over by glaciers. And, a comparison with more recent fossils could reveal whether the continental ice holds steady or advances and retreats in cycles.