for National Geographic News
Six new species of ancient bat dating back 35 million years have been discovered in Egypt, researchers say.
The new species were found by experts who analyzed 33 fossils—including teeth and jawbones—that had been unearthed over a period of decades in El Faiyum, an oasis region 50 miles southwest of Cairo (see map).
"It is [a] surprising diversity of new forms—we didn't expect to find nearly as many new kinds of bats as we found in the sample," said Gregg F. Gunnell, a paleontologist at the University of Michigan who led the study.
The experts were also surprised to find that the new species were similar to some modern-day microbats, a group of bats that uses sonar waves to navigate and hunt in a process called echolocation.
"They are all pretty primitive members of modern groups, which is a little bit odd," Gunnell said.
"Generally in [this period in the fossil record], you tend to [find] archaic bats but nothing very modern, but these animals are all members of living families."
The link is the best evidence yet that modern bats evolved on the African continent rather than in the Northern Hemisphere, as some have theorized.
"In a sense, Africa is sort of a crucible for the evolution of the modern bats," Gunnell said.
Among the newly discovered species was a previously unknown "giant" version of the microbat family, which makes it perhaps the largest of the echolocating species yet found.
The newfound fossil bats date to the Eocene epoch—56 million to 34 million years ago—and such finds are rare in Africa, the experts say.
Only a few fragmentary remains from Egypt, Morocco, Tanzania, and Tunisia have ever been discovered (see map of Africa).
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