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Early women had to go forth and multiply, while men stayed home Prof Yash
Pal |
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Early women had to go forth and multiply, while men stayed home Virtually nothing is known about how these ape-like people lived, but analysis of their teeth suggests males lived and died where they were born while females moved from their birthplace to raise families many miles away, where they then died. The findings suggest ancestral populations had a social structure that depended on males living in one area, and possibly defending their territory against intruders, whilst females moved from one place to another when they reached adolescence, either voluntarily or by force. Researchers said the findings show a difference between the sexes in terms of roaming. They suggest the pattern is similar to how young female chimpanzees tend to move away from their family, which avoids inbreeding with male relatives. Sandi Copeland of the University of Colorado at Boulder said the strontium chemical isotopes of the fossilised teeth were being used to study general migratory patterns, but that the male-female distinction soon emerged. “We were somewhat surprised at our major finding that there were statistical differences between (the sexes)... At least 50 per cent of females did not grow up in the area where they eventually died,” Dr Copeland said. “Here we have the first direct glimpse of the geographic movements of early hominids, and it appears the females preferentially moved away from their residential groups,” she said. The 19 teeth that formed the study came from two early ancestral species, Australopithecus africanus, which is believed to be a direct human ancestor, and Paranthropus robustus, a side-branch of the ancestral tree that eventually gave rise to the genus Homo. Both species lived in the same region of South Africa in caves about a mile apart, although P. robustus lived about 1.7 million years ago compared to the 2-2.7 million years of A. africanus. Tiny fragments of tooth enamel were analysed by laser ablation for strontium isotopes. The ratio of the isotopes laid down when the enamel is formed usually matches the ratio found in the surrounding plants, soil and rock where the individual lives at that time. “The strontium isotope ratios are a direct reflection of the foods these hominids ate, which in turn are a reflection of the local geology,” said Dr Copeland. The study, published in the journal Nature, concentrated on two types of teeth — the canines and the third molars — which are known to be different in terms of size between the sexes. Larger teeth were assumed to be from males with smaller teeth from females. About 90 per cent of the males appear to have lived and died in the place they were born, compared to only about half of the females. The scientists said the limited range of the males raised questions about the origins of bipedalism — walking on two legs — which was thought to have arisen in order for males in particular to roam long distances in search of food. “The ranging of the landscape seems to be a little more restricted than we at first thought and it seems to be divided along lines of male and females,” Dr Copeland said. “We assumed more of the hominids would be from non-local areas, since it is generally thought the evolution of bipedalism was due in part to allow individuals to range longer distances.” The study was carried out with scientists from Oxford University, the Max Planck Institute in Leipzig and South Africa’s University of Cape Town.
— The Independent |
Female butterfly closes wings to avoid sex TOKYO: One kind of female butterfly mates only once in its life-and then closes its wings to avoid "harassment" when pursued by persistent and unwanted males, a Japanese researcher said. Observations of the Small Copper Butterfly, a colourful orange and black butterfly, showed that some females closed their wings when males flew by, but only when they were males of their own species, said Jun-Ya Ide, an associate professor at Kurume Institute of Technology in Fukuoka, western Japan. An end to AIDS? LONDON:
For his doctors, Timothy Ray Brown was a shot in the dark. An HIV-positive American who was cured by a unique type of bone marrow transplant, the man known as "the Berlin patient" has become an icon of what scientists hope could be the next phase of the AIDS pandemic: its end. Dramatic scientific advances since HIV was first discovered 30 years ago this week mean the virus is no longer a death sentence. Thanks to tests that detect HIV early, new antiretroviral AIDS drugs that can control the virus for decades and a range of ways to stop it being spread, 33.3 million people around the world are learning to live with HIV. Shuttle Endeavour lands after its final flight CAPE CANAVERAL, Florida:
The space shuttle Endeavour touched down at its Florida home base early on Wednesday, capping a 16-day mission to deliver a premier science experiment to the International Space Station on NASA's next-to-last shuttle flight. Sailing through night skies, the shuttle and its six-man crew glided toward the Kennedy Space Center, circling high overhead to burn off speed and setting off a pair of sonic booms, heralding the ship's homecoming. Iceland volcano producing steam, no airspace closures STOCKHOLM: Iceland's volcano is producing mostly steam rather than ash and should calm down within a few days, national police said on Thursday encouraging hopes there will be no further disruption to flights in northern Europe. The Grimsvotn volcano's eruption over the weekend, which was more powerful than an explosion one year ago at another volcano, has caused far less chaos for travellers because of new rules for airlines. But it has exposed some disarray among the authorities which decide on aviation safety. "The volcano is still active, but there is just steam and smoke," Hjalmar Bjorgvinsson, superintendent at the national police, said.— Reuters |
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THIS UNIVERSE What is the string theory? The string theory is a beautiful scientific and mathematical theory. It helps us explain the classification of different forces. However, it is not yet able to predict many results. New mathematics has been invented by string theorists, and some people think that it is wonderful maths, but not much new physics so far … I may be doing it injustice because I do not understand much of it. This might be my limitation and not of string theory. I have heard a lot about Stephen W. Hawking and his contribution to physics despite his physical disabilities. But many people think otherwise. Is this partially true because it's hard to believe a person like him giving scientific theories? Stephen Hawking is a very inventive and colourful scientist. He also has a great gift of writing about complex areas of science and life.
If the sun is the closest star to the earth, then why do we say that the Pole Star is near the path of the earth's rotation? You are mistaken. The Pole Star is not near the path of the earth's rotation. It is in the direction towards which the axis of rotation of the earth points. That is the reason that while the earth rotates, its direction does not change; the Pole Star is always to the North. Readers wanting to ask Prof Yash Pal a question can e-mail him at
palyash.pal@gmail.com |
THE fossilised teeth of early human ancestors who lived two million years ago in southern Africa have provided a remarkable insight into their social organisation, which appears to have resulted in the females moving away from their childhood homes when they reached adulthood.
He does represent an enormous will power to keep engaged with passion for understanding this complex world.
He became very famous when he analysed the production of mini black holes during big bang and suggested that they might have short life times. Many scientists have made observations looking for them.