Excavation works at the cave site Sima de los Huesos.

ITN's Channel 4 news correspondent Tom Clarke reports on what scientists are learning from stalagmites about the rainfall and changing weather patterns in a remote region of southwest Poland.

U.S. officials have decided to limit the number of American troops searching the Tora Bora cave complex for clues to Osama bin Laden's whereabouts. Despite the move, Pentagon officials continued to press Afghan commanders to probe region.