"Tiny Frogs Reveal Big Secrets of Plate Tectonics"
Earth News, Discovery News (August 7, 2010)
"Around 55 million years ago, India and China collided. Some time after that -- geologists disagree on exactly when this happened -- the Himalayan-Tibetan plateau rose skyward, creating the rugged landscape that today attracts tourists and mountain climbers from all over the world.
"Now a new study has constructed the evolution of various frog species found across eastern Asia, giving geologists a genetic clock by which they can time the upheaval of the region known as 'the roof of the world.'
"In a new article in the journal Proceedings of the National Academy of Sciences, researchers led by David Wake of the University of California, Berkley detailed how four different waves of divergence among frog species -- the point when new species are created from a common ancestor -- can be explained by four major tectonic events in the region...."
There were a few surprises here. First, the scientists found that what they'd figured was one species of frog weren't: They looked alike because they'd adapted to the same environment. Mountain streams, in this case.
(I've posted about critters that live closer to sea level adapting over the weekend. (August 8, 2010))
Another surprise was that, after they'd finished analyzing and plotting their data, they found that the smooth, gradual uplift of the Himalayas - probably wasn't. Apparently it's easier to fit the data about what was happening with the mountains to what was happening with the frogs, if you assume that the mountains went up by fits and starts.
That runs contrary to the conventional idea that the Himalayas were pushed up gradually.
This could either result in a very close examination of the frog research and geological data collected to date - or in the heretic scientists being fired. That's happened before, when someone came up with the 'wrong' answer.
I'm inclined to take the frog data seriously; partly since it's not calculated to win automatic acceptance by going along with the flow; partly since the numbers show when the periods of rapid uplift happened.
Also, because abrupt changes do happen. Like the city in Chile that was 10 miles farther west in March, than it had been in January of this year. (March 10, 2010)
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