Ambulocetus pair swimming,artwork. Ambulocetus,meaning 'walking whale',lived during the Early Eocene (50 million years ago). It represents a transitional stage in the evolution of whales from land-living animals to aquatic whales. Ambulocetus was adapted to live on both land and water. It had a long,low body with powerful limbs and webbed feet. It had a flattened tail and probably swam in an undulating style similar to otters,seals and whales. Eyes and nostrils on the top of the skull allowed Ambulocetus to hunt prey by stealth in the water,similar to crocodiles. Amphibious mammals such as Ambulocetus evolved over time to become fully aquatic,their forelimbs evolved into flippers,the hindlimbs reduced in size and their tails developed flukes,or tail fins |