There may be no game simpler than tag. To play, you need nothing but a few friends and some energy. In fact, tag is so easy to play that it reaches other primate species: Gorillas like to play, too.
Marina Davila Ross and colleagues spent three years watching and filming gorilla colonies at Germany and Swiss zoos for a study now out in Biology Letters. They shot footage of 21 different young gorillas goofing around in a game that resembles human children playing tag.
Like human tag, one gorilla runs up to another and taps, hits, or outright punches the second. The hitter then usually runs away, attempting to avoid being hit back. Davila Ross and her colleagues also noticed that, like kids, the gorillas would reverse roles, so sometimes the first hitter would be the tagger, and vice versa. All African great apes appear to play tag, and younger apes play it much more often than their elders. Tree-dwelling orangutans likely also play a similar game, but not on the ground, according to Davila Ross [Discovery News].
It’s what happens to your brain after you’re born that makes you human.
Jason Hill and colleagues were comparing the structure of newborn brains to those of adults when they came upon a striking find, documented this week in the Proceedings of the National Academy of Sciences. Clearly, the brain expands greatly as you grow from baby to adult. But the researchers discovered not only that the brain grows in a non-uniform way, but also that the parts of the brain that change most rapidly as people grow up are the same parts that changed the most as humans evolved away from our primate relatives.
The research revealed that brain regions involved in higher cognitive and executive processes—such as language and reasoning—grow about twice as much as regions associated with basic senses such vision and hearing…. “The parts of the [brain] that have grown the most to make us uniquely humans are the same regions that tend to grow the most postnatally,” Hill said [National Geographic].
Apparently, in the animal kingdom, it’s better to be a girl. We have seen that women macaques are superior conversationalists. We learned that lady humpbacks enjoy long-lasting friendships. Now research published in Current Biology shows that baboon ladies with good friends around them may live longer.
At Botswana’s Moremi Game Reserve, Joan Silk of the University of California, Los Angeles and her team spied on 44 female chacma baboons over the course of six years. Among other things, Silk looked at which girls had the most visitors and how often the women picked junk out of each other’s hair. In other words, true friendship. She also tracked each baboon’s circle of friends, seeing how each lady’s top three buddies changed over time.
Silk saw a correlation between sociability and longevity. She divided the baboons into three groups, and found that the least friendly lived 7 to 18 years, while the friendliest group lived from 10 years on (they were still kicking when the study ended). They also found that those baboons who formed stable, enduring bonds were more likely to have long lives than those with flightier friendship habits.
Chimps kill chimps. And according to a 10-year study of Ngogo chimps in Uganda, they do it to defend and extend their territory. John Mitani documented 21 chimp-on-chimp killings during the study, 18 of which his team witnessed. And when the chimps kill another, they take over its land.
Because of the 1 percent difference of DNA between us and our ape cousins, it can be irresistible to anthropomorphize them, referring to their deadly attacks upon each other with terms like “murder” or “crime.” And given the murders over territory that litter human history books, it’s hard not to see echoes of our ourselves in chimp “warfare.”
Chimpanzee warfare is of particular interest because of the possibility that both humans and chimps inherited an instinct for aggressive territoriality from their joint ancestor who lived some five million years ago. Only two previous cases of chimp warfare have been recorded, neither as clear-cut as the Ngogo case [The New York Times].
But not so fast, says DISCOVER’s own award-winning blogger Ed Yong. He contacted chimp expert Frans de Waal, who would like to dissent:
“There are many problems with this idea, not the least of which is that firm archaeological evidence for human warfare goes back only about 10-15 thousand years. And apart from chimpanzees, we have an equally close relative, the bonobo, that is remarkably peaceful… The present study provides us with a very critical piece of information of what chimpanzees may gain from attacking neighbours. How this connects with human warfare is a different story” [Not Exactly Rocket Science].
The bones of our ancestors do not speak across time with ultimate clarity. The fossils with which scientists reconstruct our family tree are often fragments that offer hints and clues to where we came from. So it comes as no surprise when, as part of the flow of science, researchers offer counter-interpretations to even the most famous of finds.
That’s what happening to Ardi.
Last October Ardipithecus ramidus hit the main stage when, after 17 years of study, a large team led by paleoanthropologist Tim White published its work in the journal Science. The 4.4-million-year-old find shakes up our understanding of our own history, White said—primarily the story of how and when we learned to walk.
Ardi cast doubt on the widely accepted view that our ancestors became bipeds because they left the forest and entered a flatland savanna habitat that demanded it. But Ardi appeared to be a kind of hybrid, comfortable in the trees and on the ground. And, White said, analysis of the site where the fossil was found indicated that Ardi lived in a woodland habitat. If it’s true that early humans walked in the woods, then the “savanna hypothesis” would be swept away.
But not so fast. In today’s edition of Science, two teams of scientists respond (1, 2) with doubts about the story of Ardi.
Do chimpanzees truly understand the concept of death–and do they grieve for their dead? Two separate studies due to be published in journal Current Biology suggest that chimps may have emotional responses to death that aren’t so different from humans’ reactions.
In the first study, researchers observed an ailing female chimp in a Scottish zoo. The elderly chimp, called Pansy, was believed to be more than 50 years old. As Pansy’s health began to falter, other chimps, including Pansy’s daughter, began to exhibit signs of concern that seemed remarkably human. They groomed Pansy more often than usual as she became lethargic, and after her death, her daughter stayed near the body for an entire night, even though she had never slept on that platform before. All of the group were subdued for several days afterwards, and avoided the place where she had died, spending long hours grooming each other [BBC].
In the second study, scientists working in the forests of Guinea observed two chimp mothers carrying around the bodies of their dead infants for weeks after their deaths. One chimp carried her dead baby around for more than 60 days, an unusually long period, according to the scientists. During the period, the babies’ bodies slowly mummified as they dried out. The bereaved mothers used tools to fend off flies [BBC].
For an in-depth examination of what these two studies reveal about our closest ancestor’s understanding of death and mortality, read Ed Yong’s post in the DISCOVER blog “Not Exactly Rocket Science.”
Last week’s meeting of the Convention on International Trade in Endangered Species (CITES) put the spotlight on marine species like the bluefin tuna and some endangered sharks, as the meeting failed to protect them from being overfished to extinction. But a new survey published in the UK journal Mammal Review reminds us that it’s not just marine animals that are endangered by humans, but also primates.
The survey showed that despite CITES’ tight trade regulations for primates, more than a hundred primate species, from gorillas to monkeys to tiny lorises, are endangered by traditional medicine. The survey found that animals across the world were being hunted and killed for their perceived magical or medicinal values–of the 390 species studied, 101, or more than a quarter, are regularly killed for their body parts, with 47 species being used for their supposed medicinal properties, 34 for use in magical or religious practices, and 20 for both purposes [BBC].
The survey found that people still use primate parts to treat a wide variety of ailments. In Bolivia, spider monkey parts are used to cure snake bites, spider bites, fever, coughs, colds, shoulder pain, and sleeping problems; in India, the survey found that many people believe that macaque blood is a cure for asthma. Other monkeys or lorises have their bones or skulls ground up into powder administered with tea, or have their gall bladders ingested or blood or fat used as ointments [BBC]. Monkeys are also valued in Sierra Leone, where a small piece of chimpanzee bone is tied to a child’s waist or wrist, as parents believe it will make the child stronger as he grows older.
When vervet monkeys play follow the leader, they prefer to follow a female. That was the conclusion of Erica van de Waal, whose lengthy study of these primates in South Africa will be published this week in the Proceedings of the Royal Society B. When her team presented them with a tricky contraption they had to open to reach a tasty snack, the monkeys learned better if they watched a female from their group demonstrate the solution rather than a male.
Seeking some answers to how social learning works in monkeys, van de Waal and her colleagues headed to Loskop Dam Nature Reserve. It took four months, they say, just to acclimate the wild animals to the presence of humans. Once the monkeys were comfortable having scientists around, Van de Waal gave each group a wooden box containing a slice of apple. To get to the apple, the monkeys had to either pull open the door at one end or slide aside a door at the other. Half the box was painted black to differentiate the two ends [ScienceNOW].
Don’t count out the Y chromosome just yet. Far from being in a state of decay, as some studies have suggested, a new study in Nature says the male chromosome in humans is actually evolving at a furious pace.
Study leader David Page of MIT sequenced the human Y chromosome back in 2003, and in the new study his team compares it to the male chromosome of chimpanzees. The scientists expected the two sequences to look very similar. However, while human and chimp DNA generally differ by less than 2 per cent, more than 30 per cent of the Y chromosome differed between the two species [The Times].
African chimpanzees know how to handle wildfire, as DISCOVER noted last month. But lava is a different deal. Nyamulagira, a volcano in the Democratic Republic of the Congo, began to erupt over the weekend and threatened not only the people nearby, but also the endangered primates that live in the area. The southerly lava flow appears to have spared most human settlements and the mountain gorillas of Virunga National Park, but the native chimps haven’t been so lucky.
The 40 eastern chimpanzees that live on Nyamulagira itself could still be at risk if they are surrounded by lava, and as the plants they rely on for food become coated by abrasive volcanic ash. Park officials hope animals in the lava’s path will simply move away from it [New Scientist]. United Nations peacekeepers, who are in the Congo to protect civilians from the seemingly unending war there, have offered the country’s leaders the use of UN planes and helicopters to monitor the situation.
When it comes to understanding fire, chimpanzees might have a leg up not only on the rest of the animal kingdom, but also on those of us in the human species who would sprint in the other direction at the sight of a blaze. A study published in the American Journal of Physical Anthropology argues that these primates don’t panic when the flames start, and could even understand the basics about how fire behaves.
Primatologist Jill Pruetz has been observing chimps in Senegal since 2001, but it was in 2006 that she first noticed how the animals reacted to wildfire. When people in the area set fires to clear the land, the chimps refused to tuck tail and run. “It was the end of the dry season, so the fires burn so hot and burn up trees really fast, and they were so calm about it,” Pruetz said of the chimps. “They were a lot better than I was, that’s for sure” [LiveScience].
Last week, seemingly out of nowhere, Oklahoma State University president Burns Hargis pulled the plug on a federally funded research project that would have tested anthrax vaccines on baboons, and euthanized the primates at the experiment’s end. This week more details are beginning to come out regarding why Hargis made his call. Basically, his office says, they didn’t want to deal with possibly violent animal rights protesters.
The plan was to expose the animals to the spores of the attenuated Sterne strain of anthrax and eventually advance to the Ames strain — the fully encapsulated and virulent form of the bacterium that was used in the anthrax attacks of 2001 — and observe the pathobiology of infection. It was part of a collaborative multi-institutional NIH grant originally awarded for $12 million in 2004, and renewed in September of this year for another $14.3 million [The Scientist]. Oklahoma State would have hosted only a small part of the research, and the university’s animal testing committee approved the project unanimously.
Birds, whales, monkeys, and other animals constantly demonstrate simple communication through a variety of sounds. But one thing that has always separated them from humans, scientists thought, is that they haven’t achieved syntax—stringing together multiple different sounds to create another meaning, or what we might think of as a sentence. Now, in a study published in yesterday’s Proceedings of the National Academy of Sciences, researchers argue that they have observed monkeys using these rudimentary rules of grammar.
Klaus Zuberbühler and his team previously established the meanings of specific calls among the Campbell’s monkeys in the Tai National Park of the Ivory Coast, like the sound they dubbed “krak,” which by itself means a leopard approaches. This time, however, they documented call combinations. The monkeys can vary the call by adding the suffix “-oo”: “krak-oo” seems to be a general word for predator, but one given in a special context — when monkeys hear but do not see a predator, or when they hear the alarm calls of another species known as the Diana monkey [The New York Times].
If NASA ever wants to send astronauts on long-term space flights, it needs to know how radiation will affect the crew. Testing humans obviously isn’t going to happen, so NASA is funding a round of experiments to study how radiation effects monkeys, the first time monkeys have been used as test subjects by NASA in decades. The point of the experiments is to understand how the harsh radioactive environment of space affects human bodies and behavior and what countermeasures can be developed to make long-duration spaceflight safe for travelers beyond Earth’s protective magnetic shield [Discovery News].The monkey studies will advance previous radiation experiments with rats and mice and will focus on how radiation affects the monkeys’ central nervous system.
Researchers will expose 18 to 28 squirrel monkeys with a small dose of radiation, similar to what astronauts would receive on a round trip flight to Mars. The monkeys, previously trained to perform a variety of tasks, will be tested to see how the exposure affects their performance [Telegraph] at different times after exposure to gamma rays.The monkeys will not be killed during the experiments, and after testing staff and veterinarians will look after them for the rest of their lives at Harvard Medical School’s McLean Hospital in Boston.
Surprise, surprise. An independent analysis of the primate fossil that was unveiled amid extraordinary hype last May has found significant evidence that the lemur-like creature was not a direct ancestor of humans, after all. The 47-million-year old fossil described in May, which was given the scientific name Darwinius masillae and nicknamed Ida, was announced with unrestrained razzmatazz. She was the “eighth wonder of the world”, “our Mona Lisa” and an evolutionary “Rosetta Stone”, according to the researchers who unveiled her…. She was, they said, the “link” between us and the rest of the animal kingdom [The Guardian].
But Ida, who was the subject of both a book and a TV special that were released at the same time as the scientific paper describing the fossil, failed to wow many evolutionary biologists. Says Erik Seiffert, lead researcher of the new study: ”The suggestion that Ida [was]… specifically related to the higher primates, namely monkeys, apes and humans, was actually a minority view from the start. So it came as a surprise to many of us who are studying primate palaeontology” [BBC News].
Seiffert’s new analysis began with his attempt to identify another fossil primate, Afradapis longicristatus, which he found to be a close relation to Darwinius. The researchers then compared 360 specific anatomical features of 117 living and extinct primate species to draw up a family tree [AP]. The analysis showed that both primates are located on an early twig of the branch that produced lemurs, and far from the lineage that spawned monkeys and great apes [Wired.com]. What’s more, the researchers say that both species have no modern descendants.
80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles on the day's most compelling topics.
80beats is written by Veronique Greenwood and Valerie Ross. This team darts through each day's science news faster than the ruby-throated hummingbird that beats its wings 80 times per second. Send ideas, tips, suggestions, and complaints to [azeeberg at discovermagazine dot com].
It’s what happens to your brain after you’re born that makes you human.
Chimps kill chimps. And according to a 10-year study of Ngogo chimps in Uganda, they do it to defend and extend their territory. John Mitani documented 21 chimp-on-chimp killings during the study, 18 of which his team witnessed. And when the chimps kill another, they take over its land.
The bones of our ancestors do not speak across time with ultimate clarity. The fossils with which scientists reconstruct our family tree are often fragments that offer hints and clues to where we came from. So it comes as no surprise when, as part of the flow of science, researchers offer counter-interpretations to even the most famous of finds.
Last week’s meeting of the Convention on International Trade in Endangered Species (
When vervet monkeys play follow the leader, they prefer to follow a female. That was the conclusion of Erica van de Waal, whose lengthy 
Don’t count out the Y chromosome just yet. Far from being in a state of decay, as some studies have suggested, a new 
African chimpanzees know how to handle wildfire, 
When it comes to understanding fire, chimpanzees might have a leg up not only on the rest of the animal kingdom, but also on those of us in the human species who would sprint in the other direction at the sight of a blaze. A 
Last week, seemingly out of nowhere, Oklahoma State University president Burns Hargis 
Birds, whales, monkeys, and other animals constantly demonstrate simple communication through a variety of sounds. But one thing that has always separated them from humans, scientists thought, is that they haven’t achieved syntax—stringing together multiple different sounds to create another meaning, or what we might think of as a sentence. Now, in a study published in yesterday’s 
If NASA ever wants to send astronauts on long-term 
Surprise, surprise. An independent analysis of the primate fossil that was 
