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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 European Commission has proposed a ban on medical research performed on our species’ closest relatives, the great apes. The pan-European initiative would extend a ban already in force in Austria, Great Britain, the Netherlands, and Sweden across the entire 27-member bloc. The ban, however, would not greatly affect current research, because no testing has been carried out on great apes in the EU for the past six years [The Scientist]. Nevertheless, the proposal [pdf] has received mixed reviews from both the scientific community, who fear excessive red tape, and animal rights groups, who say the ban does not go far enough.

If approved, the ban would prohibit researchers from using great apes, including chimpanzees, bonobos, gorillas, and orangutans, to test scientific “procedures,” although behavioral studies will still be allowed. There will also be exceptions for research that could save a great ape species threatened with extinction and in the case of a serious pandemic that affects humans. The proposal also affects research on other animals, stressing the “3Rs” of reducing the number of animals used, refining techniques to lessen pain and discomfort, and replacing animal studies with alternatives [ScienceNOW Daily News]. Some 12 million vertebrate animals are used each year in experiments throughout the 27-nation bloc — half for drug development and testing, a third for biology studies and the rest for cosmetics tests, toxicology and disease diagnosis [Reuters].

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In a new study, researchers attached electrodes to individual neurons in monkeys’ brains and then rerouted those neuronal signals through a brain-machine interface, which converted them into electrical signals that controlled the monkeys’ own paralyzed muscles. Researchers say this roundabout feat of bioengineering could eventually lead to new treatments and prosthetics for paralyzed people.

The implant exploits the fact that even when the neural connection between a brain region and the muscles it controls is severed or damaged by, say, a stroke or spinal injury, the controlling neurons remain active. For example, people living with quadriplegia who try to move their arm still generate arm-movement signals in the motor cortex of their brain, even after several years of paralysis [New Scientist]. The new study is the first to send the signals back to the user’s own muscles, as opposed to related research in which the signals are fed into electronic devices.

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A new study has dealt a blow to the reputation of bonobos as and the most loving and caring of primates. Researchers following the apes through the forests of the Democratic Republic of Congo observed 5 instances when the bonobos hunted monkeys, including three successful hunts where the apes began devouring their prey even before it was dead. Says lead researcher Gottfried Hohmann: “Bonobos are merciless…. [T]hey catch it and start eating it. They don’t bother to kill it” [New Scientist].

While bonobos primarily eat fruit, researchers have known for some time that the apes supplement their diet with rodents and small antelopes. This study is the first to include other primates in their food supply, a finding that shows them to be surprisingly similar to chimpanzees, who sometimes hunt monkeys. Bonobos are generally considered more peaceful than their close cousins, the chimps, and have a reputation for free-loving ways because sex plays a major role their society, being used for greetings, conflict resolution and reconciliation [Reuters].

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The debate over bushmeat, meat from wild animals like gorillas, elephants, and antelope in Central Africa, just got more complicated. While some environmentalists have argued that a strict hunting ban is the only way to save endangered animals, a new report from the non-profit Centre for International Forestry Research (CIFOR) argues that a blanket hunting ban would help neither the animals nor the people who depend on them for food.

However, bushmeat hunting also can’t continue at its current rate, the report states. “If current levels of hunting persist in Central Africa, bush meat protein supplies will fall dramatically, and a significant number of forest mammals will become extinct in less than 50 years” [Telegraph], says report author Robert Nasi. The best solution is to legalize some hunting while enacting tough regulations and enforcement, says CIFOR director Frances Seymour: “Criminalising the whole issue of bushmeat simply drives it underground. We need to decriminalise parts of this hunting and trade and give local communities the rights and incentives to manage these resources sustainably for their own benefit” [BBC News].

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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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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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An ambitious study of all the primates on planet Earth has found that almost half of all species are threatened by extinction because of habitat loss and poaching. The latest Red List of Threatened Species, drawn up by the International Union for Conservation of Nature (IUCN), says that almost 50 per cent of the world’s 634 types of primate may disappear forever [Telegraph].

The findings highlight the multiplying threats facing primates throughout Africa, Asia, and South America, says IUCN official Russell Mittermeier: “Tropical forest destruction has always been the main cause, but now it appears that hunting is just as serious a threat in some areas, even where the habitat is still quite intact. In many places, primates are quite literally being eaten to extinction” [Bloomberg]. The study results were announced at the current International Primatological Society meeting.

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Orangutans, which some scientists believe are second only to humans in intelligence, could be the first great ape to go extinct if swift action isn’t taken to conserve their rainforest habitat and protect them from poachers, according to a new survey.

The orange-furred primates live in the wild on only two islands, Sumatra and Borneo. The survey, which was conducted by the Great Ape Trust and will be published this month in the journal Oryx [subscription required], alarmed researchers because it showed that orangutan populations have plummeted in just the last few years. It found that the number of orang-utans on Sumatra island in Indonesia has fallen by 14 per cent since 2004 to only 6,600 animals…. In Malaysia’s Borneo island, the largest home of the species, numbers fell by 10 per cent in the same period to 49,600 apes [Telegraph].

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It’s clearly a historic occasion, albeit a weird one: The Spanish parliament has announced its support for granting legal rights to gorillas, chimpanzees, and orangutans. The parliament’s environmental committee has approved resolutions committing the country to the Great Apes Project, an international campaign that aims to provide our closest genetic relatives with the right to life, the freedom of liberty and protection from torture [Great Ape Project]. The Spanish resolutions have majority support, and are expected to soon become law.

“This is a historic moment in the struggle for animal rights,” Pedro Pozas, the Spanish director of the Great Apes Project, told The Times. “It will doubtless be remembered as a key moment in the defence of our evolutionary comrades.”… Mr. Pozas said that the vote would set a precedent, establishing legal rights for animals that could be extended to other species. “We are seeking to break the species barrier — we are just the point of the spear,” he said. [The Times].

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British psychologist Simon Townsend certainly picked an interesting line of work. Instead of getting bogged down in human neuroses, he chose to spend 10 months camping in the Budongo Forest of Uganda, monitoring the active sex lives of a group of chimpanzees and making audio recordings of their sexual encounters.

Besides providing fodder for interesting cocktail party conversations, Townsend also made some interesting discoveries about when and why female chimps cry out during mating. He found that they stay silent when mating with a low-status male, but let out loud “copulation calls” when mating with a high-status fellow. However, they’re also likely to stay silent if there’s a high-status female nearby who might break up the tryst.

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This can only lead to a summer blockbuster. Researchers implanted tiny electrodes in two monkeys’ brains, allowing them to move robotic arms with their thoughts.

To motivate the monkeys to perform, they were encouraged to feed themselves marshmallows and pieces of fruit with the robotic arms, which had joints and “grippers” that roughly replicated fingers. According to the research team’s report in Nature [subscription required], the arms’ movements were fluid and natural, and the monkeys continuously adjusted the speed and direction of their robotic limbs.

While the technology isn’t yet ready for human testing, scientists are hopeful that it can eventually be applied to prosthetic limbs for people with spinal cord injuries, strokes, and other paralyzing conditions.

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