The evolution of a group of muscled frogs scattered throughout Asia is telling geologists about the sequence of events that led to the rise of the Himalayas and the Tibetan plateau starting more than 55 million years ago.
Scientists from Kunming, China, and the University of California, Berkeley, conducted a genetic analysis of 24 species of spiny frogs from the tribe Paini that shows how these Asian frogs evolved along with the mountains' uplift, developing hard, nubby spines and Popeye-like arms to hold onto their mates in the swift-running streams roaring down from the highest mountains in the world.
The sequence of evolutionary changes, in turn, tells geologists the sequence in which mountain ranges and river systems arose and isolated frog populations as a result of the Indian tectonic plate pushing northward into Asia.
"Geologists know a lot about that area, but what they haven't been able to do is give a sequence to the timing of the rise of particular mountain masses and particular ridges and pieces," said co-author David Wake, a herpetologist and evolutionary biologist and professor of integrative biology at UC Berkeley. "We use these frogs as a surrogate for a time machine."
"What we have here," he explained, "is a group of very old frogs that are so fixed to their habitats that they just stuck there, sitting on that mountain mass when it got raised up. They were separated by these uplifts and by the rivers between the mountains into different units, and these give us a fix on the timing of geological events."
Wake and his colleagues, including first author Jing Che of the Kunming Institute of Zoology, who performed some of the genetic analyses while a visiting scholar at UC Berkeley from 2008-2009, published their research in this week's print edition of the journal Proceedings of the National Academy of Sciences. A photo of the spiny frog Quasipaa boulengeri from the mountains of Sichuan,
|Contact: Robert Sanders|
University of California - Berkeley