Professor Thewissen said of the find that
the body looked pretty much like a large dog. The head had all
the features of a whale in terms of its teeth and in the ear.
It was different from most land mammals in that the eyes were
very close set, the snout was very long, and the tail was very
muscular and long.
The animals had distinctive ankle bones like those
of cloven-hoofed mammals. They also had bones in their ears that are
unique to the whale family. The new fossils superbly documented the
link between modern whales and their land-based forebears, according
to Christian de Muizon, of the Centre National de la Recherche
Scientifique, Paris, France. According to him, the first whale was
not swimming in the seas but was instead walking on land.
The two other newly-found fossils were of later
creatures, ones which were further down the path towards aquatic
life. The skeletons were approximately 47 million years old, and
also came from Pakistan.
These early whales used powerful webbed hind legs
to swim, like otters, and could probably move on land as well.
University of Michigan palaeontology professor Philip Gingerich
discovered the fossils after a decade-long search.
It was clear to Professor Gingerich that these
animals could hitch their way out of water and back in like sea
lions do today, but they were more aquatic than may originally
have been realised.
Scientists have long known that whales, dolphins
and porpoises - the cetaceans - are descended from land mammals
with four limbs. The adaptation from mammals to whales is thought
to have taken place over a span of about fifteen million years,
starting around 50 million years ago, and all on or around the
Indian subcontinent at a time at which this had only just begun
its slow and steady collision with Asia.