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The theory that Oetzi the Iceman died in a violent fight with others has received further support from scientists in Australia.
The researchers say their DNA study of
items found with the 5,300-year-old hunter's body back up the
idea that he was involved in close-quarter combat. Ferocious battle Then further tests on the body revealed
a deep wound on Oetzi's right hand and wrist which, according
to the findings, were inflicted in the last few hours of the
iceman's life. Diplomatic impasse "He probably got into a skirmish with
some other people and eventually got shot in the back," he
said. Who did it? Oetzi was about 159 centimetres (five
feet, 2.5 inches) tall, 46 years old, arthritic, and infested
with whipworm.
Scientists have unearthed remains of a primate that could have been ancestral not only to humans but to all great apes, including chimps and gorillas.
The partial skeleton of this 13-million-year-old "missing link" was found by palaeontologists working at a dig site near Barcelona in Spain. Details of the sensational discovery appear in Science magazine. The new specimen was probably male, a fruit-eater and was slightly smaller than a chimpanzee, researchers say.
Palaeontologists were just getting started at the dig when a bulldozer churned up a tooth. Further investigation yielded one of the most complete ape skeletons known from the Miocene Epoch (about 22 to 5.5 million years ago). Salvador Moyà-Solà of the Miquel Crusafont Institute of Palaeontology in Barcelona and colleagues subsequently found parts of the skull, ribcage, spine, hands and feet, along with other bones. They have assigned it to an entirely new family and species: Pierolapithecus catalaunicus. Monkey business Great apes are thought - on the basis of genetic and other evidence - to have separated from another primate group known as the lesser apes some time between 11 and 16 million years ago (The lesser apes include gibbons and siamang). It is fascinating, therefore, for a specimen like Pierolapithecus to turn up right in this window. Scientists think the creature lived after the lesser apes went their own evolutionary way, but before the great apes began their own diversification into different forms such as orang-utans, gorillas, chimps and, of course, humans. "Pierolapithecus probably is, or is very close to, the last common ancestor of great apes and humans," said Professor Moyà-Solà.
The new ape's ribcage, lower spine and wrist display signs of specialised climbing abilities that link it with modern great apes, say the researchers. The overall orthograde - or upright - body design of this animal and modern-day great apes is thought to be an adaptation to vertical climbing and suspending the body from branches. The Miocene ape fossil record is patchy; so finding such a complete fossil from this time period is unprecedented. "It's very impressive because of its completeness," David Begun, professor of palaeoanthropology at the University of Toronto, Canada, told the BBC News website. "I think the authors are right that it fills a gap between the first apes to arrive in Europe and the fossil apes that more closely resemble those living today." Planet of the apes Other scientists working on fossil apes were delighted by the discovery. But not all were convinced by the conclusions drawn by the Spanish researchers. Professor Begun considers it unlikely that Pierolapithecus was ancestral to orang-utans. "I haven't seen the original fossils. But there are four or five important features of the face, in particular, that seem to be closer to African apes," he explained. "To me the possibility exists that it is already on the evolutionary line to African apes and humans."
Professor David Pilbeam, director of the Peadbody Museum in Cambridge, US, was even more sceptical about the relationship of Pierolapithecus to modern great apes: "To me it's a very long stretch to link this to any of the living apes," he told the BBC News website. "I think it's unlikely that you would find relatives of the apes that live today in equatorial Africa and Asia up in Europe. "But it's interesting in that it appears to show some adaptations towards having a trunk that's upright because it's suspending itself [from branches]. "It also has some features that show quadrupedal (four-legged) behaviour. Not quadrupedal in the way chimps or gorillas are, but more in the way that monkeys are - putting their fingers down flat," he explained. During the Miocene, Earth really was the planet of the apes. As many as 100 different ape species roamed the Old World, from France to China in Eurasia and from Kenya to Namibia in Africa.
Faulty genes feed nicotine habit
People who find it difficult to clear nicotine from their body may be more vulnerable to getting hooked on smoking, research suggests Scientists found people who carry a gene mutation which slows this process are more likely to find it tough to quit smoking. The effect was especially strong in new young smokers who carried rogue versions of the CYP2A6 gene. The research is published in the journal Tobacco Control.
The researchers analysed data from almost 1,200 13-year-olds in Quebec, of which 228 smoked, but were not yet addicted when the study started. During the two year period of the study 67 of the smokers ended up fully hooked on nicotine. Genetic analysis showed that dependency was significantly more likely in those who carried one of two faulty versions of the gene, both of which sabotages the ability of the liver to break down and remove nicotine from the system. They were almost three times as likely to become addicted to tobacco as those with the normal variants of the gene. People who carried partially inactive variants of the gene were not at increased risk of becoming addicted. Numbers consumed Students with the normal gene smoked an average of 29 cigarettes a week. Those with the partially inactive variant smoked 17. But those with the inactive variant, which slowed down nicotine clearance the most, smoked around 12 cigarettes a week. The authors suggest that slow clearance prolongs the exposure of the brain to nicotine and is likely to make it more intense. This may increase the likelihood of addiction - and reduce the number of cigarettes required to achieve it. Thus, although young smokers who carry the faulty genes are likely to smoke less, they are also likely to find it more difficult to give up. Previous research has shown that it is much harder for those who become chemically dependent on nicotine to quit smoking. In March, Oxford University researchers pinpointed variations of a gene that controls dopamine, a brain chemical associated with feelings of pleasure, as playing a key role in smoking addiction. Women who had a minor variant of this gene were only half as likely to quit smoking and stay off tobacco, in an experiment that involved nicotine patches. 'Don't take it up' Dame Helena Shovelton, chief executive of the British Lung Foundation, said: "This research shows once again that for some smokers, nicotine is horribly addictive and therefore difficult to give up. "About 450 children start smoking each day - these are appalling statistics - especially when you consider this research suggests that young smokers get hooked more easily." Professor John Britton of the British Thoracic Society said: "This study is further evidence of the crucial role played by nicotine in establishing a lifelong and lethal addiction to cigarettes. "Our focus must be to prevent young taking from up smoking in the first place, and evidence suggests the best way is to drive down the prevalence of smoking in adults."
Combined test for genetic defects
An ingenious DNA fingerprinting test could detect telltale signs of Down's syndrome, and a series of devastating single gene disorders. The test is being offered to parents in Australia who are undergoing IVF because they want their child to avoid disorders such as cystic fibrosis.
Parents who opt for pre-implantation screening do not have fertility problems, but during IVF, doctors have access to fertilised embryos outside the body and can take the opportunity to run tests on them. The defective gene involved is passed to some offspring, but not others, and doctors screen the embryos to select and implant only those which do not carry them. Risk of age Many of these have already had a child with the disorder, and, as a result, are either in their 40s, when they opt for screening. The mother's age substantially increases the chance that a child might also have Down's syndrome - but the new test can rule this out, and help doctors select embryos with no sign of either defect. It avoids the need for the mother to have a separate test, amniocentesis, which in a small number of cases, can cause a spontaneous miscarriage. It was developed at the Monash Institute of Reproduction and Development by Mandy Katz, a PhD student. She said that prior to her test, an embryo could be declared free of a single gene defect, yet still be carrying Down's. She said: "It would be a tragedy if, after these parents got the all-clear from the pre-implantation genetic test, they found out their child had Down's syndrome." Down's, which occurs in one in every 700 live births, is caused by an extra bundle of genetic information, called chromosome 21. Children born with the defect have differing degrees of developmental problems, and distinctive facial features. They are also more likely to have congenital heart defects which require surgery. Ms Katz said that the DNA fingerprinting technique was more cost-effective and only needed a single cell to make both diagnoses. The accuracy of the Down's test was as much as 94%, she said. The research team is now hoping to extend the combined test to cover other single-gene defects, so that more parents could be helped.
Big day 'can't slow cancer
death'
There is no truth in the belief - based on
anecdotal evidence - that cancer patients can delay their death for
important events, a US study suggests. An Ohi o State University team looked at 300,000 cancer deaths over 12 years.They found no evidence of unusual death rate patterns near birthdays, Christmas and Thanksgiving, they told the Journal of the American Medical Association . Many carers tell of patients who seem to defy the odds by staying alive long enough to witness an important event. Sheer willpower Health care workers and others close to patients dying of cancer commonly recall how they die immediately afterwards. And previous studies have noted an apparent dip or peak death pattern associated with significant religious and social events.
Some believe that patients are able to cheat death by sheer willpower alone, or perhaps by some unknown psychosomatic mechanism.However, the latest analysis showed no significant difference in the proportion of patients dying in the week after a potentially significant event, compared with the proportion dying the in the week before it. In fact, women were more likely to die of cancer in the week before their birthday, than the week after it. Researcher Dr Donn Young said: "I think all of us may know or have heard of someone 'hanging on' through the holidays or trying to live until an important occasion. "But the figures just don't bear this out as something that people can really do. "I think the most important thing for all of us to take away from this is the notion of attending to what is important. "In other words, don't put off what is meaningful in life. Do it now, before it is too late." A recent discussion paper in the journal Psychosomatic Medicine found previous studies which suggested there may be some truth to the theory were methodologically flawed. None had provided any direct evidence of a psychophysiological mechanism enabling people to postpone or hasten their own death. Professor Thomas Wise is an expert in psychiatry and behavioural sciences at Johns Hopkins University in Baltimore and editor of Psychosomatic Medicine. He said: "The real reason why we hold to this theory is our wish to have control over the most sentinel event in our lives following birth - death."
How our ancestors avoided cancer
Cancer is a disease that touches most people's lives in some way. We all seem to know someone who has had it and the global picture is far from encouraging with incidence rates rising year on year. The increase is largely explained by the fact that the population is steadily ageing, but it is also associated with unhealthy lifestyles, smoking and obesity.
So what of our ancestors? Did they face a life shortened by cancer or were they healthier than modern man? Research on skeletons dating back thousands of years, indicates that cancer was not something they encountered very frequently. Dr Mario Slaus of the Croatian Academy of Sciences and Arts in Zagreb, carried out tests on the skeletal remains of more than 3,000 individuals for evidence of neoplasms - uncontrolled and abnormal tissue growth. The bones in the academy collection dated from 5,300 BC to the 19th century AD and had been collected from archaeological sites across Croatia.
Analysis revealed four cases of neoplastic disease in individuals ranging from three-to-four to 50-60 years of age. All four cases involved bone neoplasms, but all were benign, with little potential to become malignant. Dr Slaus said: "We found no evidence of secondary bone tumours in any individual in the collection, a factor that is probably explained by the fact that the mean age-at-death of the specimens is 35.6 years. "Primary malignant and benign tumours of bone are relatively rare, even in young individuals where the incidence of these neoplasms is highest, while secondary tumours of bone, although much more common, are associated with older age." Modern lifestyles Dr Slaus's view is that our ancestors would have died early from other common ailments and would not have survived long enough for cancer to take hold. Life expectancy in the 21st century is higher than it has ever been in the past, mainly due to better nutrition, improved health awareness, better sanitation and more accessible health care. However, increased longevity is accompanied by an increased incidence of cancer. The factors linked with the development of cancer in the West are smoking (estimated to cause about 30% of cancer deaths) and obesity/dietary factors (estimated to be responsible for a further 30% of all cancer deaths). However, these factors can take many years to lead to the development of symptomatic tumours, so ageing populations naturally show a higher incidence of the disease. "The individuals in the Croatian skeleton collection would have been prone to diseases such as syphilis, tuberculosis and leprosy and we found evidence for each of these conditions in individuals in the collection," said Dr Slaus. "These illnesses and others would have certainly contributed significantly to mortality in our ancestors," he added. "The change from these 'old' illnesses to 'modern' ones such as cancer can be seen as part of the evolution of our society, but as with the 'old' illnesses we can go some way to combating the 'modern' illness of cancer through educating people about the risks of the disease and encouraging them to adopt a healthy lifestyle," said Dr Slaus. Healthy options Cancer Research UK said it was no surprise to find a low incidence of cancer in a collection of individuals whose average age of death was 35 years. The charity's science information officer Dr Elaine Vickers said: "Cancer is primarily a disease of older people, as it is generally the result of the DNA damage that accumulates over a person's lifetime. "In fact, 65% of cancers occur in people over 65 years of age.
"As the average life expectancy in the UK has almost doubled since the mid-19th century, the population at risk of cancer has also grown. "Our risk of cancer is also influenced by our environment and lifestyle. "For example, smoking is the single largest cause of cancer, and the mass-production of cigarettes only began in the late 19th century. "You can reduce your risk of cancer by not smoking, eating plenty of fresh fruit and vegetables, reducing your alcohol intake, maintaining a healthy body weight, and protecting your skin from the harmful effects of the sun." Life was tough for the people whose remains lie in the Croatian Academy. Our lives are somewhat easier and we have more control over them, but because we often take them for granted, we are in danger of contributing to the cancer epidemic. The earlier we change our habits, the better and we may give scientists of the future something else to talk about.
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This research shows once again that for some smokers, nicotine
is horribly addictive.
