Re: Whales and Hippos

["Neil Taylor (Home)" <nf.taylor@ntlworld.com>]

At 04:27 20/09/2001, you wrote:
> Story on evolutionary relationships between whales, hippos, and etc. can 
> be found at:
>
> http://www.cbc.ca/cgi-bin/templates/view.cgi?/news/2001/09/19/whale_hippos010919

the BBC site has some nice pictures too; it also appeared in print in at 
least some of today's papers.

http://news.bbc.co.uk/hi/english/sci/tech/newsid_1553000/1553008.stm

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By BBC News Online's Helen Briggs
Fossils of the early land-based ancestors of whales have been unearthed in 
Pakistan.
The 50-million-year-old bones represent a "missing link" between primitive 
hoofed mammals and the whale family.
And the remains also fill in some of the gaps in the fossil record between 
four-legged mammals and modern whales.
The predators were about the size of a wolf and were well adapted to 
running. They belonged to a group called pakicetids.
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.
Scientists believe the creatures developed a taste for fish, learned to 
swim and eventually took to the water altogether.
Over the course of time, their descendants lost their limbs and became 
fully adapted to a marine environment.
The bones were unearthed last October by palaeontologists from the United 
States and Pakistan.
Hans Thewissen, of the Northeastern Ohio Universities College of Medicine, 
Rootstown, US, was a member of the team that found the fossils.
He told BBC News Online: "The body looks basically like a large dog. The 
head has all the features of a whale in the teeth and the ear.
"It's different from most land mammals in that the eyes are very close set, 
the snout is very long and the tail is very muscular and long."

Hippo's cousin?
Scientists have long known that whales, dolphins and porpoises - the 
cetaceans - are descended from land mammals with four limbs.
But this is the first time fossils have been found with features of both 
whales and land mammals.
The find could help resolve a long-standing debate over the evolutionary 
link between whales and hippos.
It confirms genetic research placing whales' origin within the ungulate 
(hoofed animal) group. The whale's closest living relative may well be the 
hippopotamus.
Commenting on the research, Christian de Muizon of the Centre National de 
la Recherche Scientifique, Paris, France, said the new fossils superbly 
documented the link between modern whales and their land-based forebears.
"The first whale was not swimming but walking on land," Dr de Muizon told 
BBC News Online.
"You can imagine this animal living close to the mouth of a river. 
Little-by-little, it shifted to an aquatic carnivorous diet.
"It became more and more adapted to water. After a few million years, it 
became better adapted to an aquatic environment becoming an amphibious 
animal like a sea lion."
The research is reported in the journal Nature.
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-- Neil Taylor "Creo Imaginem Mente"