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Stories of modern science ...

By JIM KLING, UPI Science Writer

, Nov. 7 (UPI) -- EARLIER RISE OF MODERN HUMAN BEHAVIOR

New evidence suggests that Homo sapiens -- modern humans -- emerged from Africa fully modern behaviors that had evolved much earlier than previously thought. Among the evidence: a large set of specialized bone tools in South Africa, which, at 70,000 years old, shows that humans have been using bone technology twice as long as had previously been thought. The finding will appear in the December edition of the Journal of Human Evolution. "The real implications are that there was modern human behavior in Africa about 35,000 years before Europe," said lead author Christopher S. Henshilwood, affiliate archaeologist at Iziko - South African Museum in Cape Town, and adjunct associate professor of archaeology at the State University of New York at Stony Brook. The standard theory is that humans became anatomically modern 150,000 to 200,000 years ago, but their behavior didn't change significantly until about 40,000 to 50,000 years ago, "when they suddenly changed and then moved into Europe and elsewhere," said Henshilwood. "Once again, in terms of human evolution, we are seeing Africa as being precocious: Bipedal hominids evolved in Africa; the first real increase in brain size occurred in Africa; and now, we are beginning to see that the last great advance, the development of modern behavior, was made in Africa as well," said Curtis W. Marean of the Institute of Human Origins at Arizona State University.

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LONGER-LASTING SPECIES FOLLOW MASS EXTINCTIONS

Species that evolve immediately following mass extinctions have a tendency to survive in the fossil record for longer periods of time. University of Cincinnati professor Arnold Miller examined longevity trends in fossils from the Phanerozoic era, which covers the last 540 million years. It was already known that species evolving after mass die-offs tended to be generalists capable of living in a range of habitats and geographic locations. "My analysis indicates that these characteristics promoted evolutionary longevity," said Miller. One enigma in the analysis is that the pattern does not extend back into the Paleozoic, the earliest of the three eras that comprise the Phanerozoic. Miller said that it is possible that there was a change in the dynamics of evolution after the Paleozoic, but he said any real explanation has yet to be determined.


A ONE HOUR TEST FOR ANTHRAX

Researchers at the Mayo Clinic have developed a new DNA test that can identify anthrax in human and environmental samples in one hour. The company Roche Diagnostics is making the test widely available to public health agencies, hospital laboratories and reference laboratories in the United States and other countries. "The first thing people want to know in a case of suspected exposure is whether the agent was in fact anthrax," said Franklin R. Cockerill, III, the Mayo Clinic microbiologist who led the development team. "Until now, local labs have been able to quickly determine the presence of a bacterium, but they can't tell whether it is anthrax or not. The current process to identify the presence of anthrax may take several days. The events of the last several weeks require as rapid a response as possible."

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They also plan to disseminate the test to regional and local laboratories. "This rapid identification will enable doctors to begin more timely treatment of patients who have been exposed to anthrax, and it will more quickly alleviate undue anxiety for people who haven't been exposed," said Cockerill.


FIRST IMAGE OF THE INSIDE OF A SUNSPOT

U.S. researchers have sound waves to picture what goes on inside a sunspot. The image shows fast-moving streams of hot, electrically charged gas swirling beneath the surface of the Sun. "What we found is that sunspots are not static but consist of very strong, downward flows of plasma - electrically charged gas - traveling toward the interior of the Sun at speeds of about 4,800 kilometers per hour (3,000 miles per hour)," Alexander Kosovichev of Stanford`s Hansen Experimental Physics Laboratory told the BBC. The data came from the Solar and Heliospheric Observatory (Soho) satellite, which is stationed about 1.6 million kilometers (a million miles) from Earth. Its Michelson Doppler Imager (MDI) generates images by measuring the velocity of sound waves as they pass through the Sun, similar to what happens in a medical ultrasound. The images showed that deep within sunspots, material rushes towards the center of the sun like a whirlpool, partially countering the flow of heat from the center of the Sun outward and thus causing the sunspot to be slightly cooled. "The cool sunspot continues to cool the material around it, which consequently sinks," said Douglas Gough, professor of theoretical astrophysics at the University of Cambridge in England. "One of the striking features of these observations is just how shallow a sunspot is," he continued. "There have been purely theoretical debates in the past about how deep sunspots might be, but these observations have given us the answer."

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(Editor; for more information on behavior, call 480-965-6375; on extinction, call 513-556-1806)

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