- Ambulocetus
Taxobox
name = "Ambulocetus"
fossil_range = EarlyEocene
image_width = 270px
regnum =Animal ia
phylum = Chordata
classis =Mammalia
ordo =Cetacea
subordo =Archaeoceti
familia =Ambulocetidae
subfamilia =Ambulocetinae
genus = "Ambulocetus"
species = "A. natans"
binomial = "Ambulocetus natans"
binomial_authority = Thewissen et al.,1996 "Ambulocetus" ("walking whale") was an early
cetacean that could walk as well as swim. It lived during earlyEocene some 50-49 million years ago. It is atransitional fossil that shows howwhale s evolved from land-livingmammal s. Having the appearance of a 3 metre long mammaliancrocodile , it was clearly amphibious, as its back legs are better adapted for swimming than for walking on land, and it probably swam by undulating its back vertically, asotter s andwhale s do. It has been speculated that Ambulocetids hunted like crocodiles, lurking in the shallows to snatch unsuspecting prey. Chemical analysis of its teeth shows that it was able to move between salt and fresh water."Ambulocetus" did not have external ears. To detect prey on land, they may have lowered their heads to the ground and felt for vibrations.Scientists consider "Ambulocetus" to be an early whale because it shares underwater adaptations with them: it had an adaptation in the
nose that enabled it to swallow underwater, and itsperiotic bone s had a structure like those of whales, enabling it to hear well underwater. In addition, its teeth are similar to those of cetaceans.The "Ambulocetus" fossils were found in
Pakistan by anthropologist Johannes Thewissen. When the animal was alive, Pakistan was a coastal region bordering the ancientTethys Sea .See also
*
Evolution of cetaceans References
*
External links
* [http://www.bbc.co.uk/nature/wildfacts/factfiles/432.shtml BBC Online]
* [http://www.neoucom.edu/DEPTS/ANAT/Thewissen/whale_origins/whales/Ambulocet.html Ambulocetidae: The First Costal Whales] by J. G. M. Thewissen.
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