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filthy
SFN Die Hard
USA
14408 Posts |
 Posted - 03/12/2008 : 16:27:33
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But I'm not telling it so fear not, you'll have no problem staying awake during this read.
These are some of the most fascinating fossils of Cetaceans yet found. They nicely tell much of the story of some of the most remarkable species to ever roam the planet. It is also the story of the research.
Research on the Origin and Early Evolution of Whales (Cetacea)
Introduction
The mammalian order Cetacea is divided into three suborders: (1) Oligocene to Recent Odontoceti or 'toothed whales'— living today; (2) Oligocene to Recent Mysticeti or 'baleen whales'— living today; and (3) older and more primitive Eocene Archaeoceti or 'archaic whales'— which evolved from land mammals and gave rise to later odontocetes and mysticetes. My research on the origin and early evolution of whales is focused on archaeocetes. I have been fortunate to work with many colleagues on this in Egypt, Jordan, Pakistan, and India, (see co-authors in the publication list below). The stages of early whale evolution that we have documented are shown here in Figure 1. We have found and collected virtually complete skeletons of middle-to-late Eocene Basilosauridae (Dorudon and Basilosaurus), exceptionally complete skeletons of middle Eocene Protocetidae (especially Rodhocetus and Artiocetus), and a partial skull of earliest middle Eocene Pakicetidae (Pakicetus). Recovery of diagnostic ankle bones in the skeletons of primitive protocetids during our field work in Pakistan in 2000 confirmed their derivation from Artiodactyla (the mammalian order including cows, deer, hippos, etc.), and showed convincingly that whales did not originate from mesonychid condylarths as Van Valen hypothesized (and we had expected).
Figure 5. Virtually complete skeleton of Dorudon atrox excavated in Wadi Hitan, Egypt. Note the retention of hind limbs, feet, and toes like those found in Basilosaurus. This find is described in Uhen (1996, 2004). The skeleton is approximately 5 m long. Photograph ©1998 Philip Gingerich. Figure may be reproduced for non-profit educational use.
This is a damned good study -- enjoy!
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist! 
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A whale of a tale....
