"Amazing Productive" Green Sahara
. d% K! G" q: N2 w/ B& ? These winged creatures' light and flimsy bones seldom survive as fossils, and examples from Africa are especially rare.
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2 U) C8 j) w, W "All the pterosaur material that has ever been found in Africa could fit on a very small table," he said.$ D' n2 f. _; x* c" }- E* L
' H% z, F/ T4 `. r3 \ But Ibrahim and colleagues got lucky during their expedition: They found similarly aged fossil fragments that belonged two other previously unknown and unrelated pterosaurs.
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' m7 V3 V0 R0 h Q These discoveries suggest that several different pterosaur species lived side by side, eating different prey in the ancient river delta.* }: f# v- C" K1 B" C# X
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For instance, one of the two yet-to-be described species had long, thin teeth that may have been used for grabbing fish while gliding over water.; g* \; m, H! ~/ ~) y
* t: x" ]! t( ^6 o/ Z Surrounded by dry land, this wet ecosystem also supported diverse forms of crocodiles and dinosaurs, Ibrahim noted.
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2 z9 l/ Y* x0 r. ^4 Y) J "It was such an amazingly productive environment," he said. |
发表于 2012-8-14 23:21:39
