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An undated photograph shows the inside of the Vindija cave in Croatia, where a leg bone from a male Neanderthal was found and and used to sequence DNA by researchers who on Wednesdauy said it shows that Neanderthals are truly distant relatives of modern humans who interbred rarely, if at all, with our own immediate ancestors. (Johannes Krause- Max- Planck Institute of Evolutionary Anthropology/Handout/Reuters) Researchers have sequenced DNA from the leg bone of a Neanderthal man who died 38,000 years ago and said on Wednesday it shows the Neanderthals are truly distant relatives of modern humans who interbred rarely,...

Neanderthals may have given the modern humans who replaced them a priceless gift -- a gene that helped them develop superior brains, U.S. researchers reported on Tuesday. And the only way they could have provided that gift would have been by interbreeding, the team at the Howard Hughes Medical Institute and the University of Chicago said. Their study, published in the Proceedings of the National Academy of Sciences, provides indirect evidence that modern Homo sapiens and so-called Neanderthals interbred at some point when they lived side by side in Europe. "Finding evidence of mixing is not all that surprising. But...

Researchers peering into the DNA toolbox have found yet another instrument of evolution. Simply replicating a piece of a particular gene--from one copy in mice to more than 200 in humans--may have prompted some of the changes in the brain that define us as human, according to a new study. Evolution occurs when genes mutate, or when they alter where, when, and how strongly they are active. In addition, hiccups in DNA replication can foster change by causing some parts of genes to be repeated as they are copied. Twin genes or duplicated regulatory regions result, and although one in...

Ira Block/National GeographicSome scientists say this skull, smaller than those of modern humans, is from a newfound species. Not all scientists agree that the 18,000-year-old "little people" fossils found on the Indonesian island of Flores should be designated an extinct human-related species. Some expressed their opposition in news interviews and informal symposiums, but papers arguing their case were rejected by major journals. snip... In today's issue of the journal Science, researchers led by Robert D. Martin of the Field Museum in Chicago present evidence they say supports their main argument, that the skull in question is not that of...

Maybe they just didn't have time to get to know each other. The question of what Neanderthals and Homo sapiens might have done on cold nights in their caves, if they happened to get together and the fire burned down to embers, has intrigued scientists since the 19th century, when the existence of Neanderthals was discovered. A correction in the way prehistoric time is measured using radiocarbon dating, described last week in the journal Nature, doesn't answer the enduring question, but it might at least help explain why no DNA evidence of interbreeding has been found: the two species spent...

Earwax may not play a prominent part in human history but at least a small role for it has now been found by a team of Japanese researchers. Earwax comes in two types, wet and dry. The wet form predominates in Africa and Europe, where 97 percent or more of people have it, and the dry form among East Asians. The populations of South and Central Asia are roughly half and half. By comparing the DNA of Japanese with each type, the researchers were able to identify the gene that controls which type a person has, they report in today's...

Durham, NC - Researchers have discovered the first brain regulatory gene that shows clear evidence of evolution from lower primates to humans. They said the evolution of humans might well have depended in part on hyperactivation of the gene, called prodynorphin (PDYN), that plays critical roles in regulating perception, behavior and memory. They reported that, compared to lower primates, humans possess a distinctive variant in a regulatory segment of the prodynorphin gene, which is a precursor molecule for a range of regulatory proteins called "neuropeptides." This variant increases the amount of prodynorphin produced in the brain. While the researchers do...

This article is for suscribers only. If you suscribe go here: http://www.sciencenews.org/pages/search_results.asp If you don't here is an abstract that the article is based on: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16274263&query_hl=2 The work studies the endorphin, prodynorphin in Chimps and Humans. It purports to show that "This is the first documented instance of a nueral gene that has had its regulation shaped by natural selection during human origins" (Matthew Hahn, U. Indiana). Human generally contain 2-4 copies of the regulatory sequence in contrast to one copy for chimps, gorillas, orangutans, baboons and macaques. The investigators contend that changes in the prodynorphin regulatory sequence must have...

Researchers at the Universities of Michigan and California looked at the ratio of older and younger adult teeth found at sites up to 100,000 years old. Finding more older teeth in the Upper Palaeolithic suggests the grandparent role - being on hand to help out more - became more common at that time. The research is in the Proceedings of the US National Academy of Sciences. Big advantage After studying more than 750 fossilised teeth anthropologists Rachel Caspari and Sang-Hee Lee noticed they were finding more specimens from older adults in more recent sites. Modern humans were older and wiser...

It's only a short step from feeling angry to feeling angry at someone, especially if that person is of a different social group, sex or ethnicity. At least that is what psychologists who are investigating the link between emotions and prejudice are finding. In a study that measured how emotional states affected views of outsiders, the researchers, from Northeastern University and the University of Massachusetts at Amherst, found that anger increased the likelihood of a negative reaction to members of a different group and that sadness or a neutral emotion did not. The study will appear in the May issue...

Another species has been added to the family tree of early human ancestors — and to controversies over how straight or tangled were the branches of that tree. Long before Homo erectus, Australopithecus afarensis (Lucy, more than three million years ago) and several other distant kin, scientists are reporting today, there lived a primitive hominid species in what is now Ethiopia about 5.5 million to 5.8 million years ago. That would make the newly recognizied species one of the earliest known human ancestors, perhaps one of the first to emerge after the chimpanzee and human lineages diverged from a common...

Illustration by Michael Rothman Before An Australopithecus, sporting full-bodied fur about four million years ago. After An archaic human walked fur-free about 1.2 million years ago, carrying fire on the savanna ONE of the most distinctive evolutionary changes as humans parted company from their fellow apes was their loss of body hair. But why and when human body hair disappeared, together with the matter of when people first started to wear clothes, are questions that have long lain beyond the reach of archaeology and paleontology. Ingenious solutions to both issues have now been proposed, independently, by two research groups analyzing...

To the Editor: "The Beginning of Modern Humans" (editorial, June 15) states that a newly discovered Ethiopian skull more than 150,000 years old is "recognizably modern to paleoanthropologists but not to most of the rest of us." It does not look recognizably modern to this paleoanthropologist, and it is a much less probable candidate for being the ancestor of the modern European human than the European Neanderthal is. I have superimposed the outlines of the crania being compared. Statistical analysis of a battery of measurements shows that the European Neanderthal is more closely related to modern Europeans than to anyone...

Origin Of Bipedalism Closely Tied To Environmental Changes Champaign - May 01, 2002 During the past 100 years, scientists have tossed around a great many hypotheses about the evolutionary route to bipedalism, to what inspired our prehuman ancestors to stand up straight and amble off on two feet. Now, after an extensive study of evolutionary, anatomical and fossil evidence, a team of paleoanthropologists has narrowed down the number of tenable hypotheses to explain bipedalism and our prehuman ancestors' method of navigating their world before they began walking upright. The hypothesis they found the most support for regarding the origin of...

The World's No.1 Science & Technology News Service Scientists sort the chimps from the men 19:00 11 April 02 NewScientist.com news service A team of molecular biologists have taken a step towards defining what makes us human. It is not so much our differing gene sequences that distinguish us from our primate cousins, but how active those genes are, the team has discovered. Chimp and human genomes vary by only 1.3 per cent and only a tiny fraction of this actually affects genes. The new research shows how variation in the amount of product of a gene may be as...