A fossil found in Argentina of a large carnivorous bird capable of eating dog-sized mammals challenges traditional thoughts on how birds evolved.
The fossil of a 10-foot tall phorusrhacid, or "terror bird," was discovered in 15 million-year-old rocks in Argentina's southern Patagonia region near Comallo, Argentina, the (London) Telegraph said Tuesday. Bones recovered included a limb bone and 28-inch, nearly intact skull with an eagle-like bill.
The flightless phorusrhacid could capture and eat dog-sized creatures roaming South America millions of years ago, the Telegraph said.
The discovery suggests that these birds, thought to weigh up to 1,000 pounds, may have been more agile and less heavy than thought, and capable of running up to 30 mph. The currently accepted view is that as they evolved the birds became slower and less agile because they grew fatter.
Experts said they believe that the extinct birds were carnivores because their beaks resemble those of eagles and vultures.
Copyright 2006 by United Press International
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