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filthy
SFN Die Hard
USA
14408 Posts |
 Posted - 02/04/2009 : 17:18:26
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I've a whale of a tale to tell ye, lads,
A whale of a tale, it's true,
About the flappin' fish and the girls I've loved,
On a night like this with the moon above.
I've a whale of a tale and it's all true,
I swear by my tattoo!
And here's a whale of a tale!
"If you take a look at a whale or dolphin–any whale or dolphin anywhere on Earth–it will follow certain rules. It will have a blowhole. It will not have legs. It will have horizontal tail flukes it raises and lowers to swim (as opposed to fish that bend from side to side). And it will have been born tail first (as opposed to the head-first position of land mammals). These sorts of rules set whales and dolphins off from other living animals, but only if you look at life as it is today. If you move back in time–especially back between about 50 million and 40 million years ago–the rules collapse.
As I detailed in my book, At the Water's Edge, paleontologists began to document the transition whales made from land to sea in the late 1970s. University of Michigan paleontologist Phil Gingerich found the skull of a mammal that seemed like it belonged to a land mammal but had some hallmarks known only in whales. Over the past three decades, he and other paleontologists have found a menagerie of magnificently weird whales. They start out able to walk on land and then gradually adapted to living in the water. Their noses crept up their heads, becoming blowholes. They swam at first kicking like otters, then more like seals, and then finally like whales do today.
Of course, the dozens of early whale species paleontologists have discovered are probably only a fraction of the diversity that actually existed. And so whenever new species turn up, paleontologists can use them to test hypotheses about how whales evolved. Gingerich and his colleagues are publishing the details of one today, called Maiacetus, that shines a particularly amazing light on early whale evolution. That's because they've found fossils of both adult males and female Maiacetus–as well as a baby Maiacetus still in her mother."
Got pointed at it by PZ.
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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 tale of a whale…
