Takashi Hososhima, Flickr
Laughs and smiles in chimps turn out to be far more human-like than previously thought and they date to at least 5 million years ago, suggests a new study on chimpanzee facial expressions and vocalizations. Laughter is not 100 percent identical between the two primates, but people who hear a chuckling chimp usually have little trouble figuring out what the sound generally means. Chimps go "h-h-h," while humans sound more like "ha-ha-ha" or "he-he-he," said Marina Davila Ross, a senior lecturer in the University of Portsmouth's Department of Psychology and lead author of the study in PLOS ONE. Then there is the flexibility of the sounds and related expressions. "Chimpanzees, like humans, can produce their facial expressions free from their vocalizations," Ross explained. "This ability is important for humans. For instance, it allows us to add a smile while talking or laughing, and we can also produce smiles silently. Until now, we did not know that non-human primates also have this ability." It's even possible that the skills first emerged in the common ancestor of chimps and humans.Video: Apes Giggle Like Humans
Tambako The Jaguar, Flickr
In both humans and chimps, facial expressions associated with laughter and happiness usually involve an open mouth with a display of teeth. "Open mouth expressions, otherwise known as play faces, or as we call them, laugh faces, typically expose the lower teeth by virtue of the mouth being wide or stretched open," co-author Kim Bard, who is a professor of comparative developmental psychology at the University of Portsmouth, told Discovery News. "We found that there were many types of open mouth expressions, including some configurations with the upper lip drawn up, which sometimes exposes the upper teeth."6 Shocking Things About Chimps
Kim A. Bard
Little Callie the chimp, shown in this photo, is enjoying a good laugh with a human friend. Chimps, like people, sometimes laugh and smile when they are alone, too. "We know that laughter and open mouth faces occur mostly during play, but they can occur in solitary play as well as social play," Bard said. "So our current theory is that laughter (in chimps) is typically associated with feelings of joy."Chimps 'Talk' About Their Favorite Foods, Trees
Both young chimps and children tend to laugh and smile a lot, probably because they play more than adults do (and have less to worry about). But why would teeth be exposed as a sign of friendliness? Some experts suspect that the open mouth/exposed teeth expression, during non-threatening play times, allows the other individual to learn how to assess others and to adjust their reactions. Another theory is that a toothy smile often is a visual signal of submissiveness, given that the jaws are usually drawn backward as opposed to the forward thrust of a "grrr" sound and related facial expression.Apes Enjoy Slapstick Humor
Josh A. Schneider
Since laughter is seen and heard by others, it works wonders as a social bonding tool. In this case, the baby chimp is laughing as its mother tickles its stomach. The researchers suspect that bonobos, like chimps and humans, also benefit from this type of bonding, and have very flexible facial expressions and vocalizations.Video: Why Are We Ticklish?
Marina Davila Ross and Kim A. Bard
So far, observations of chimps show they are always honest laughers, meaning that the sounds function as true signals of joy. People, on the other hand, are notorious for fake laughter. We can smile and laugh as though we are happy, even when we're not. There is, however, a complex twist to chimp laughter: what elicits happiness in some might not in others. "I've seen adolescent males (chimps) who sometimes exhibit bullying behavior, laughing softly while they are picking on another chimpanzee, who is usually not enjoying the interaction," Bard said. "When the victim gets annoyed enough to try to stop the bullying behavior, then the adolescent can respond with greater laughter, which is even more annoying!" "So the laughter is 'joyful,'" she said, "but the adolescent finds picking on another chimpanzee, and even their attempt at retaliation, to be something that brings the adolescent some joy."Wild Chimps Glug Alcohol Using Homemade Tools
Marina Davila Ross and Kim A. Bard
Studying the origin of laughter and smiles could help researchers better understand disorders such as autism. This condition is characterized, in part, by difficulties communicating via such signals, and in forming relationships with others. The research also helps us to better understand the abilities of non-human primates, and our evolutionary connections to them. As this image and the one before it show, there's not much difference between a chimp "laugh face" and the typical expression of humans as they enjoy a good guffaw.
The largest ape to roam Earth died out 100,000 years ago because it failed to tuck into savannah grass after climate change hit its preferred diet of forest fruit, scientists suggest.
Gigantopithecus — the closest Nature ever came to producing a real King Kong — weighed five times as much as an adult man and probably stood three metres (nine feet) tall, according to sketchy estimates.
In its heyday a million years ago, it inhabited semi-tropical forests in southern China and mainland Southeast Asia.
Until now, though, almost nothing was known about the giant's anatomical shape or habits.
The only fossil records are four partial lower jaws, and perhaps a thousand teeth — the first of which turned up in the 1930s in Hong Kong apothecaries where they were sold as “dragon's teeth."
These meagre remains “are clearly insufficient to say if the animal was bipedal or quadrupedal, and what would be its body proportions," Herve Bocherens, a researcher at Tübingen University in Germany, told AFP.
Its closest modern cousin is the orangutan, but whether Gigantopithecus had the same golden-red hue, or was black like a gorilla is unknown.
A comparison graph of a 1.8-meter-tall human male in comparison to Gigantopithecus blacki (left) and G. giganteus (right): This graph is based on orangutan proportions while standing upright.WikiMedia Commons/Public Domain
Another mystery: its diet. Was it a meat-eater or a vegetarian? Did it share a taste for bamboo with its neighbor the prehistoric giant panda?
Answering this riddle might also tell us why a monster that surely had little to fear from other fauna went extinct.
That's where the teeth had a story to tell.
Examining slight variations in carbon isotopes found in tooth enamel, Bocherens and an international team of scientists showed that the primordial King Kong lived only in the forest, was a strict vegetarian, and probably wasn't crazy about bamboo.
These narrow preferences did not pose a problem for Gigantopithecus until Earth was struck by a massive ice age during the Pleistocene Epoch, which stretched from about 2.6 million to 12,000 years ago.
That's when Nature, evolution -- and perhaps a refusal to try new foods -- conspired to doom the giant ape, Bocherens explained.
"Due to its size, Gigantopithecus presumably depended on a large amount of food," he said.
"When during the Pleistocene, more and more forested area turned into savannah landscapes, there was simply an insufficient food supply."
And yet, according to the study, other apes and early humans in Africa that had comparable dental gear were able to survive similar transitions by eating the leaves, grass and roots offered by their new environments.
But for some reason, Asia's giant ape -- which was probably too heavy to climb trees, or swing in their branches -- did not make the switch.
"Gigantopithecus probably did not have the same ecological flexibility and possibly lacked the physiological ability to resist stress and food shortage," notes the study, which is to be published in a specialist journal, Quaternary International.
Whether the mega-ape could have adapted to a changing world but didn't, or whether it was doomed by climate and its genes, is probably one mystery that will never be solved.
Climate change several hundred thousand years ago was also likely responsible for the disappearance of many other large animals from the Asians continent.