Original source URL: http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/05/18/wchimp118.xml Men mated with chimps for 1m years (Filed: 18/05/2006) The human family tree has been thrown into disarray by evidence that the ancestors of man and chimpanzees kept on mating with each other for a million years or more. Studies of fossils have suggested that the ancestors of humans had started to walk upright seven million years ago. A study released today by Harvard Medical School and Massachusetts Institute of Technology suggests that men interbred with their ape cousins until at least 6.3 million years ago, making the boundaries between the species fuzzy. The evolutionary split between human and chimpanzee is much more recent - and more complicated - than previously thought, blurring the distiction between different branches of our family tree and also explaining the small difference in ape and human genetic codes today. The study, published in the journal Nature, shows that the speciation process was unusual - possibly involving an initial split followed by interbreeding before a final separation. _______________________________________________ http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/05/18/wchimp18.xml The monkeys who can speak in sentences By Roger Highfield, Science Editor (Filed: 18/05/2006) The first evidence that monkeys string "words" together to say more complicated things, as humans do, is published today by scientists. Simple vocal languages use a different sound for every different meaning. But there is a limit to the range of sounds that can be made and easily distinguished. So for complicated messages it is more efficient to combine basic sounds in different ways to convey different meanings. A team at the University of St Andrews reports today in the journal Nature that male putty-nosed monkeys (Cercopithecus nictitans) in West Africa can combine different sounds to construct new messages, a remarkable discovery. During three years of observations of the monkeys in the Gashaka Gumti National Park, Nigeria, Dr Kate Arnold and Dr Klaus Zuberbühler found that the creatures use their two main call types - "pyows" and "hacks" - to warn each other against predators. They also noticed that a particular sequence of calls appeared to mean something else entirely when strung together, depending on the circumstances. A string of pyows warns against a loitering leopard, while a burst of hacks indicates a hovering crowned eagle. But a sentence made up of several pyows followed by a few hacks tells the group to move to safer terrain. Dr Arnold, a primate psychologist, discovered the phenomena by playing leopard growls and variations of the calls back to the monkeys and seeing how they behaved. "These calls were not produced randomly and a number of distinct patterns emerged," she said. "The pyow-hack sequence means something like 'let's go' whereas the pyows by themselves have multiple functions and the hacks are generally used as alarm calls." Previously, it was thought animal communication systems used one particular signal to mean one particular thing. Dr Zuberbühler added: "To our knowledge, this is the first good evidence of a syntax-like natural communication system in a non-human species." copyright of Telegraph Group Limited -- -------------------------------------------------------- Escaping the Matrix website http://escapingthematrix.org/ cyberjournal website http://cyberjournal.org subscribe cyberjournal list mailto:•••@••.••• Posting archives http://cyberjournal.org/show_archives/ Blogs: cyberjournal forum http://cyberjournal-rkm.blogspot.com/ Achieving real democracy http://harmonization.blogspot.com/ for readers of ETM http://matrixreaders.blogspot.com/ Community Empowerment http://empowermentinitiatives.blogspot.com/ Blogger made easy http://quaylargo.com/help/ezblogger.html
