Ultima Thule

In ancient times the northernmost region of the habitable world - hence, any distant, unknown or mysterious land.

Wednesday, August 30, 2006

Bird attacks influenced human evolution, researchers say

By Aussiegirl

Shades of Alfred Hitchcock!

Bird attacks influenced human evolution, researchers say

By Holly Wagner/Ohio State University
and World Science staff

Pre­his­tor­ic birds of prey may have tar­geted our an­ces­tors for meals so of­ten that the threat of them helped drive hu­man ev­o­lu­tion, re­searchers say based on a study.

An­a­ly­z­ing hun­d­reds of mo­d­ern mon­key bones ga­th­ered be­low Af­ri­can ea­g­les’ nests, the sci­en­t­ists found the birds are a se­vere me­nace to some of our pri­mate cou­sins.

They al­so con­c­lu­d­ed that the re­sult­ing bone in­ju­ries are sus­pi­cious­ly ve­ry like those on the skull of an ape-like child of hu­man an­ces­tors, found de­cades ago. It ap­pa­r­ent­ly has clawed-out eye­sock­ets, they sa­id.

“It seems that rap­tors have been a se­lec­tive force in pri­ma­te ev­o­lu­tion for a long time,” said W. Scott Mc­Graw of Ohi­o State uni­ver­si­ty, the stu­dy’s lead au­thor.

“Be­fore this stu­dy I thought that ea­g­les would­n’t con­t­ri­b­ute that much to the mor­tal­i­ty rate of pri­mates in the fo­r­est. I could­n’t have been more wrong.”

The ide­a that birds ate ear­ly hu­mans is­n’t new. A 1995 stu­dy sug­gested that the pre­his­tor­ic 3½-year-old “Taung Child,” whose skull turned up in a South Af­ri­can ca­ve in 1924, might have been a vic­tim of such an in­ci­dent. But sci­en­tists saw the ev­i­dence as in­con­clu­sive.

McGraw, though, ar­gued that punc­ture marks on mon­key skulls close­ly re­sem­ble those found on the Taung skull, of the spe­cies Aus­t­ra­lo­pi­the­cus af­ri­ca­nus. “Ea­gles leave ve­ry dis­tinc­tive beak and tal­on punc­tures around the face and in the eye sock­et­s,” he ar­gued. “The skull of the Taung child has these same kinds of punc­ture mark­s.”

“This fos­sil is pro­b­a­bly the most writ­ten-a­bout, stu­d­ied and han­dled ho­m­i­nid skull ev­er,” he added. “But al­most no one had real­ly bo­th­ered to look at skulls dis­carded from ea­gle nests” to ce­ment the case against birds. [....]


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