The concept of Pennsylvania palmettos and magnolias in Minnesota may not be too far-fetched in view of research by a University of Florida paleontologist.
The research by vertebrate paleontologist Jonathan Bloch and colleagues suggests land plants changed drastically during a period of sudden global warming 55 million years ago.
"It indicates that should we have a period of rapid global warming on that scale today, we might expect very dramatic changes to the biota of the planet, not just the mammals and other vertebrates, but forests also completely changing," said Bloch.
Global warming allowed mammals to emigrate across northern land bridges, marking the first appearance of perissodactlys in the form of the earliest known horse; artiodactyls, a group of even-toed ungulates that includes pigs, camels and hippos; as well as modern primates, he said.
The theory is supported by excavations in northwestern Wyoming by team leader Scott Wing, a paleontologist at the Smithsonian Institution. They uncovered tropical fossil leaves and pollen alongside fossilized mammals in rocks that were deposited during that turbulent geologic interval.
The research is detailed in the current issue of the journal Science.
Copyright 2005 by United Press International
Explore further: A sub-desert savannah spread across Madrid 14 million years ago