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　　Scientists: Monkeys Used Raft to Cross Ocean

　　Scientists believe a species of monkeys used a raftto cross 160 kilometers of ocean from South toNorth America about 21 million years ago.

　　The monkeys are similar to today's capuchins, smallmonkeys that often perform with humans at thecircus.

　　Scientists found seven monkey teeth that became fossils in an area near the Panama Canal. Theteeth were more than five million years old. Scientists think that is when the continents of Northand South America came together.

　　They said the teeth belonged to a species they call Panamacebus transitus. When the specieslived, South America was not in contact with other continents.

　　For that reason, South America has a strange variety of mammals. The animals grew andchanged in interesting ways because they were separated from other animals.

　　Jonathan Bloch works at the Florida Museum of Natural History on the University of Floridacampus. He said that Panama was farther south than any other place in North America. He saidthe monkeys might have swum, but probably rode on some kind of a raft.

　　Surprising discovery

　　Bloch believes these monkeys were the only mammals that were able to cross the waterwayfrom South America to reach present-day Panama.

　　The strip of land, known as the Isthmus of Panama, was formed about 3.5 million years ago.That land bridge permitted large numbers of animals to begin walking between the continentsin one of the biggest mixing of species on record.

　　Bloch said learning that monkeys lived in North America that long ago was a surprisingdiscovery. For a long time, scientists thought that monkeys simply did not exist there.

　　It would be like learning that Australia's kangaroos and koalas live in the wilds of Asia today.