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Female macaques are much chattier than male macaques, according to a new study. The researchers say vocal communication is an important part of macaque social bonding and the findings may reflect similar patterns in the evolution of human language. Klaus Zuberbühler, who studies primate communication, says social animals communicate to resolve the constant tension between a “need to compete and a desire to cooperate” [New Scientist].

The researchers studied macaques living on Cayo Santiago island off Puerto Rico, and for three months they followed a group of macaques that consisted of 16 females and 8 males. Friendly monkey chit-chat included a variety of grunts, coos, and girneys (nasally whines, usually between mother and infant). The researchers counted the social vocalizations, excluding those that were used only to indicate food or predators, and found that females vocalized 13 times more often than the males. Researcher Nathalie Greeno says, “The results suggest that females rely on vocal communication more than males due to their need to maintain the larger social networks” [News Scientist].

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The fossilized pelvis of a Homo erectus woman who lived 1.2 million years ago on the banks of an Ethiopian river has been discovered, and while researchers say it casts new light on human evolution, some of their conclusions are challenging previous theories about these early human ancestors. The pelvis reveals a short, squat woman who wasn’t built for long-distance running, but also a woman with a wide birth canal to accommodate big-brained infants.

Study coauthor Scott Simpson says the pelvis’s wide birth canal indicates that hominds’ increasing brain size was a driving factor in human evolution. Getting through the birth canal is “the most gymnastic thing we ever do,” he says. To accommodate big-brained babies, humans must have developed larger and wider birth canals over time, but with few pelvic fossils, researchers had little idea when these changes began. The Busidima pelvis shows that a wide birth canal was already in place 1.2 million years ago [New Scientist].

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The oldest human to have his complete mitonchondrial (mtDNA) genome sequenced, a 5,000-year-old “Iceman” mummy known as Ötzi, does not appear to have any living relatives in Europe. The new genetic analysis reveals that Ötzi belonged to a previously unknown branch of human evolution. Said study coauthor Franco Rollo: “Apparently, this genetic group is no longer present…. We don’t know whether it is extinct or it has become extremely rare” [HealthDay News].

The researchers extracted DNA from Iceman’s rectum. They analyzed the genome of the cells’ energy-making structures, called mitochondria. “You only get mitochondrial DNA from your mother, and she gets it from her mother and so on, so it forms an unbroken link all the way back to the common maternal ancestor of all of us,” said researcher Martin Richards [LiveScience]. Earlier studies of fragments of Ötzi’s mtDNA had indicated that he was of the K1 lineage, which is further divided into three branches. But after comparing his complete mtDNA genome with that of 115 modern Europeans of K1 lineage, the researchers found three mutations that place Ötzi in a fourth, previously unknown, branch of K1.

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Neanderthals living in coastal caves in Gibraltar hunted and feasted on seafood, researchers say, adding another piece of evidence to the argument that Neanderthals weren’t outmatched and driven to extinction by more skilled and sophisticated Homo sapiens. “I don’t think that the success of one or the other had to do with subsistence, with the way they hunted or fed,” [researcher Clive] Finlayson said. “There may be other factors coming into this, or it may just have been a question of luck” [National Geographic News].

The discovery of seal, dolphin and fish remains in the caves dating from 60,000 to 30,000 years ago provides the first evidence that Neanderthals ate sea mammals as well as land grub. Archaeologists found the mammals’ remains among Neanderthal hearth sites in Vanguard and Gorham’s Caves on the Rock of Gibraltar. The bones of some of the animals have cut marks that were likely made by Neanderthals using flint knives, also found on site, to cut the meat off [LiveScience].

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A new analysis of the skulls of three Neanderthal babies shows that the cranium of a newborn Neanderthal was about the same size as that of a newborn Homo sapiens, and that the Neanderthal children grew faster than modern humans in the first few years of life. The report on the young skeletons, which date from between 45,000 to 50,000 years ago, adds fuel to the debate over how similar Neanderthal culture was to that of our early Homo sapiens ancestors.

A big-headed infant skeleton found in Russia suggests that childbirth was no easy task for for Neanderthal women. Neanderthal mothers had slightly larger birth canals, but the prominent face of Neanderthal babies made it just as hard to push out as a modern human. This suggests that both groups had the social structures needed to help with childbirth [New Scientist].

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Researchers have discovered a stretch of “junk” DNA that may have contributed to humanity’s evolution of opposable thumbs. When genetically engineered into mice, the human DNA seems to activate genes in the budding wrist and thumb. Chimp and monkey versions, on the other hand, seem only capable of switching on genes in the developing shoulder [New Scientist].

In a new study, the research team combed through the vast regions of human DNA that do not contain code for making proteins. Formerly dissed as “junk DNA,” sections of these non-gene regions are now known to play a regulatory role, dialing down or cranking up the activity of actual genes [Science News]. Researchers first found a long sequence of DNA that had barely changed during the entire evolution of backboned creatures, and then zeroed in on a smaller stretch of code that had accumulated 16 changes since the ancestors of humans and chimpanzees split, about 6 million years ago.

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Archaeologists have recreated the stone tools made by Neanderthals, and found them to be as useful and efficient as those made by the earliest Homo sapiens, who survived while the Neanderthal line died off. The new research is one of many recent studies claiming that Neanderthals weren’t just dumb brutes that were out-competed by early humans. Says lead researcher Metin Eren: “When we think of Neanderthals we need to stop thinking in terms of ’stupid’ or ‘less advanced’ and more in terms of ‘different’” [Guardian].

Other recent studies have argued that Neanderthals hunted and communicated as well as the early Homo sapiens who arrived in Europe, where the Neanderthals already lived, about 45,000 years ago. But some archaeologists still believed that Homo sapiens had a technological advantage, because they used long stone tools called blades, as opposed to the Neanderthals’ disk-shaped flakes. In the new study, Eren’s team spent spent three years recreating blades and flakes, then measured their cutting power, durability and the amount of effort needed to produce them [Wired News]. In the end, Eren determined that the Neanderthals’ tools may have even had a slight edge over Homo sapiens tools.

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When athletes throw a touchdown, hit a home run, or win a race, they often raise their arms straight up to celebrate. A new study suggests that these kinds of gestures are deeply rooted in our minds, and not just force of habit.

Jessica Tracy of the University of British Columbia in Vancouver, Canada, and David Matsumoto of San Francisco State University looked at pictures of judo competitors from both the 2004 Olympic Games and Paralympic Games, trying to see if blind and sighted people reacted differently to victory, since the blind could not have learned victory gestures socially by watching others. In their study, published in the Proceedings of the National Academy of Sciences [subscription required], they found that blind athletes who have never seen such a display make similar gestures of pride as sighted athletes when they win, and also slump their shoulders and narrow their chests in shame when they lose [LiveScience].

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For the first time, scientists have sequenced the mitochondrial DNA of a Neanderthal. Researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, analyzed the genetic material from a 38,000-year-old leg bone found in Croatia and published their findings today in Cell.

The mitochondria are only passed down the female line, so can be used to trace the species back to an ancestral “Eve”, the mother of all Neanderthals. The team analysed the DNA of 13 genes from the Neanderthal mitochondria and found they were distinctly different to modern humans, suggesting Neanderthals never, or rarely, interbred with early humans. The genetic material shows that a Neanderthal “Eve” lived around 660,000 years ago, when the species last shared a common ancestor with humans [Guardian].

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Cro-Magnon people and Neanderthals may have shared their European habitat from 45,000 to 30,000 years ago, but new evidence suggests that they didn’t get more intimate than that. Italian researchers sequenced mitochondrial DNA from Cro-Magnon bones dating from 28,000 years ago and found no trace of Neanderthal DNA, suggesting that the two early hominids did not interbreed to create modern humans.

The fate of the Neanderthals, who vanish from the fossil record around 30,000 years ago, has been fiercely debated. One theory, known as the Out of Africa hypothesis, holds that modern humans, whose ancestors had recently migrated from Africa, drove the Neandertals extinct, possibly through warfare, disease, or cognitive advantage. But the competing multiregional hypothesis argues that Neandertals and modern humans interbred and that Neandertals were absorbed into our gene pool [ScienceNow Daily News].

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