The finding is one of the conclusions of a two year study by geologists at the University of Florida and University of Kansas that is scheduled to appear next week in the online edition of the London Journal of the Geological Society.
By comparing separate, seemingly unrelated findings on trilobite evolution and geological history, UF's Joe Meert and KU's Bruce Lieberman concluded that precursors to modern continents began splitting off from a giant supercontinent at the South Pole about 580 million years ago, migrating north toward the equator for about 80 million years. The scientists' analysis suggests that a prominent theory holding that the continents moved far more rapidly is wrong. It also suggests that trilobites, the long-ago forbearers of crabs and lobsters, originated in present-day Siberia when it was a separate continent from Asia and located much farther south.
Trilobites probably evolved in Siberia millions of years before they appear in the fossil record, the analysis suggests. In Lieberman's words, their appearance may have supplied the "fuse" for the Cambrian radiation, the "big bang" of life that occurred about 543 million years ago.
"Siberia at the time -- it wasn't as cold and desolate place as it is today," Meert said. "It was in a better place (in the Southern hemisphere) but it's interesting that you can trace roots back."
The study is the fruit of a chance meeting that happened in spring of 2001. Meert was visiting KU to present his research. In what Meert called a "Reese's chocolate-and-peanut-butter moment," the geologists compared notes and realized they had come to the same conclusions about the origins and movement of the modern continents using vastly different methods one
Contact: Joe Meert
University of Florida