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[Press Release] ETHIOPIAN SKULL FIND HELPS PIECE TOGETHER PUZZLEArthur R. McGee (amcgee@NETCOM.COM)Wed, 4 May 1994 12:23:25 -0700
Date: Wed, 4 May 1994 05:44:35 -0400 From: NSF Document Mailer <stisop@stis.nsf.gov> Subject: [Press Release] ETHIOPIAN SKULL FIND HELPS PIECE TOGETHER PUZZLE OF HUMAN ORIGIN The file "pr9424" has been added to the STIS system. This file is an UPDATE to an existing file. Reference material is located at the end of this message. ----------------------------------------------------------------------- Title : ETHIOPIAN SKULL FIND HELPS PIECE TOGETHER PUZZLE OF HUMAN ORIGIN Type : Press Release NSF Org: OD / LPA Date : March 31, 1994 File : pr9424 Michael Fluharty March 31, 1994 (703) 306-1070 NSF PR 94-24 ETHIOPIAN SKULL FIND HELPS PIECE TOGETHER PUZZLE OF HUMAN ORIGIN A National Science Foundation-funded expedition in Ethiopia has found a three million-year-old skull thought to be from humankind's earliest known ancestors, scientists reported today [March 31] in the British journal Nature. According to the paleoanthropologists, William Kimbel and Donald Johanson from the Institute of Human Origins in Berkeley, Ca., and Yoel Rak of Tel Aviv University, this is the first time a nearly complete skull has been found from the ancient pre-human species Australopithecus afarensis. Perhaps the species' best- known specimen is "Lucy," discovered at Hadar in Ethiopia in 1974 by Johanson. The recent discovery of the skull, with its ape- like jutting jaw, small braincase and thick protruding ridges above the eyes, helps support the theories of paleoanthropologists who maintain that all three to four million-year-old fossils found in Ethiopia's Afar region come from one species. They conclude that this species later evolved into the lineage that includes modern humans. According to the scientists, the discovery means that this small-brained, upright-walking pre-human with an ape-like body existed for nearly one million years (four to three million years ago) without significant change, or nearly 200,000 years more than previously thought. -more- -2- Kimbel, Johanson, and Rak maintain that these primitive upright-walking creatures did not diversify into distinct lineages until some time after three million years ago. They say the discovery supports their view that all pre-human specimens found in the region represent the same species, a species in which males were considerably larger than females. These scientists and others are countered by colleagues who believe that the variations in fossil size and other features are too great to have come from a single species. According to this other view, there was a more "robust" species of larger boned creatures, whose lineage is now extinct, which lived at the same time as the smaller species, which evolved into humans. In their view, the two distinct lines had already diverged before the time of Lucy, more than three million years ago. According to NSF physical anthropology program director Jonathan Friedlaender, the East African Rift Valley remains the "most productive source of early proto-human fossil finds in the world." NSF programs support excavations at Hadar and other nearby sites because these results provide important information about man's earliest non-ape, but very ape-like, ancestors, he says. Rak and his assistants found the skull in fragments on a hillside near a dry river bed. It is one of 53 such fossils found in the area during the past four years by the IHO team and their Ethiopian colleagues. The age of the skull was determined by its location between two layers of volcanic rock. Because the rock contains potassium, the rate at which potassium radioactively decays can be used to accurately date each layer using a technique called single crystal laser fusion, which compares the ratios of two isotopes in single rock crystals. -end- The National Science Foundation is an independent agency of the federal government established in 1950 to promote and advance scientific progress in the United States. NSF accomplishes its mission primarily by competitively awarding grants to educational institutions for research and education in the sciences, mathematics, and engineering. This and other information is available electronically on STIS, NSF's Science and Technology Information System. For more information about STIS contact the Publications Section at (703) 306-1130 and request the "STIS Flyer," NSF Publication #94-4, or send an E-mail message to stisinfo@nsf.gov (INTERNET) or stisinfo@NSF (BITNET). ----------------------------------------------------------------------- End of pr9424 ----------------------------------------------------------------------- ** FOR YOUR REFERENCE ** This message was mailed to the STIS mailing list "PRESS". To get off the list, send the following message to "ListProc@nsf.gov" (Internet): unsubscribe PRESS If you receive an error message, send the following message for more information: help unsubscribe If, after 24 hours, you haven't received *any* response from Listserver, send a message to "stis@nsf.gov" (Internet). A human will read your message.
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