Ambulocetus was an early cetacean that could walk as well as swim. Along with other members of Ambulocetidae, it is a transitional fossil that shows how whales evolved from land-living mammals. It is also named as the walking whale because of this.Ambulocetus lived in the Early Eocene (50 to 48 million years ago) of Pakistan. When the animal was alive, Pakistan was a coastal region of India, which was then an island continent in the Indian Ocean (see Indian Plate).