Post by Berter on Jul 26, 2004 16:36:31 GMT -5
A Very Tiny Ancestor
Scientists fill in a piece of the evolutionary puzzle
by Erika Check | mars 27 '00
Smaller than a fingernail, the tiny bone is, at first glance, an insignificant sliver. But under the microscope, its slightly eroded features hint at an amazing past. Scientists believe the bone once belonged to a small primate that spent its life chowing down on nectar and insects in a rain forest 45 million years ago. An ancient member of the group called "prosimians," the creature was a link between early primates and those that came after them--including us. The tiny animal could fill in a blank in our understanding of human evolution.
Anthropologist Dan Gebo and colleagues report on this and other finds from a quarry in China in the Journal of Human Evolution and last week's issue of Nature. Gebo's team also found bones from extinct mammals called Eosimias at the quarry. These creatures resemble prosimians, but they're the oldest-known members of the "anthropoid" primate branch--the group that includes monkeys, apes and humans. That makes Eosimias a crucial link in human evolution. "Without Eosimias," says Gebo, "there are no monkeys, no apes and no humans."
The new finds raise an interesting question. If humans originated in Africa, what are our precursors doing in Asia? Gebo guesses that early primates like Eosimias migrated from Asia to Africa, where they evolved into baboons, chimps and people. "The human evolutionary story begins in Africa--there's no doubt about that," says Gebo. If he and his colleagues are right, the prequel to that story was written halfway across the world.
Newsweek U.S. Edition
http://www.keepmedia.com:/Register.do?oliID=225
Scientists fill in a piece of the evolutionary puzzle
by Erika Check | mars 27 '00
Smaller than a fingernail, the tiny bone is, at first glance, an insignificant sliver. But under the microscope, its slightly eroded features hint at an amazing past. Scientists believe the bone once belonged to a small primate that spent its life chowing down on nectar and insects in a rain forest 45 million years ago. An ancient member of the group called "prosimians," the creature was a link between early primates and those that came after them--including us. The tiny animal could fill in a blank in our understanding of human evolution.
Anthropologist Dan Gebo and colleagues report on this and other finds from a quarry in China in the Journal of Human Evolution and last week's issue of Nature. Gebo's team also found bones from extinct mammals called Eosimias at the quarry. These creatures resemble prosimians, but they're the oldest-known members of the "anthropoid" primate branch--the group that includes monkeys, apes and humans. That makes Eosimias a crucial link in human evolution. "Without Eosimias," says Gebo, "there are no monkeys, no apes and no humans."
The new finds raise an interesting question. If humans originated in Africa, what are our precursors doing in Asia? Gebo guesses that early primates like Eosimias migrated from Asia to Africa, where they evolved into baboons, chimps and people. "The human evolutionary story begins in Africa--there's no doubt about that," says Gebo. If he and his colleagues are right, the prequel to that story was written halfway across the world.
Newsweek U.S. Edition
http://www.keepmedia.com:/Register.do?oliID=225