A dwarf elephant the size of a Shetland pony once roamed the Mediterranean island of Cyprus. In the West Indies, a giant rat-like rodent tipped the scales at more than 400 pounds (180 kg ...

To investigate that, researchers turned to a sort of evolutionary second-cousin of the kangaroo, the musky rat-kangaroo. AILSA CHANG, HOST: Hopping has evolved multiple times in the animal kingdom.