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Monday, November 23, 2009 |
Monday, November 23, 2009 |
Photo: Bats Have an Aerodynamic Edge Over Birds, Study ShowsThe arrows represent air movement produced by air motion—and show that, unlike birds that generate lift only when flapping downward, bats flex their wings to create thrust both on their downstrokes and upstrokes. Illustration © Science
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ADVERTISEMENTNATIONAL GEOGRAPHIC'S PHOTO OF THE DAY |
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