Posts Tagged ‘great apes’

Your Hands Were Made For Punching According To New Study

December 20th, 2012 12:42 admin View Comments


They are capable of delicate surgery, creating beautiful works of art, and comforting someone feeling down, but according to a new study your hands evolved to smash someone in the face. From the article: “Human hands evolved so that men could make fists and fight, and not just for manual dexterity, new research finds. The study, published in the Journal of Experimental Biology, adds to a growing body of evidence that humans are among the most aggressive and violent animals on the planet. “With the notable exception of bonobos, great apes are a relatively aggressive group of mammals,” lead author David Carrier told Discovery News. “Although some primatologists may argue that chimpanzees are the most aggressive apes, I think the evidence suggests that humans are substantially more violent.”‘”

Source: Your Hands Were Made For Punching According To New Study

Polly-math Parrots Add Sophisticated Reasoning to Their List of Clever Feats

June 22nd, 2011 06:54 admin View Comments

What’s the News: Parrots are even less bird-brained than previously thought, suggests a new study in the journal Biology Letters. In a series of tests, researchers have learned that some African grey parrots can use logical reasoning to uncover hidden food.

How the Heck:

  • Sandra Mikolasch and her colleagues at the University of Vienna in Austria trained seven African grey parrots to find treats stashed under cups. While the birds watched, Mikolasch placed food under one cup and left an adjacent cup empty—the parrots had to choose the correct cup to get their snacks.
  • After training the birds, Mikolasch hid a seed and a walnut under two separate cups in front of the on-looking parrots. In plain view, she removed one of the treats and allowed the birds to choose cups again. Three of the parrots were able to correctly pick the cup with food at least 70 percent of the time. If the birds were purely guessing, they would have chosen the correct cup roughly half of the time.
  • Mikolasch repeated the experiment with one alteration: she masked her movements behind an opaque screen. She removed one of the treats and showed it to the birds, then had the birds choose cups. By noting which snack was removed, one of the parrots, Awisa, was able to deduce which cup still had food in 23 of the 30 trials (about 77 percent). The other parrots chose more randomly. Mikolasch suspects that Awisa was successful because she’s the parrot equivalent of a “whiz kid.â€

What’s the Context:

  • By the age of 4, most children are able to “infer by exclusion.†In one of Mikolasch’s previous experiments, 18 out of 20 4-year-olds were able to complete the parrots’ tasks, Mikolasch told LiveScience.
  • Scientists previously thought that great apes (including humans) were the only animals capable of this type of logical reasoning.
  • The research adds to the growing body of work documenting how smart some bird species are. In 2005, scientists trained a grey parrot to understand the concept of zero, which humans grasp at age 3 or 4. The parrot, Alex, was part of a 30-year project to study parrot intelligence. By the time he died in 2007, Alex had a vocabulary of 150 words, which included base colors and numbers, and could ask for some objects by name (such as “bananas”).
  • More recently, researchers learned that New Caledonian crows, an especially smart species, and kea parrots are able to use tools to solve puzzles.

(via LiveScience)

Image: Flickr/Drew Avery

Source: Polly-math Parrots Add Sophisticated Reasoning to Their List of Clever Feats

Orangutan Genome: The Orange Apes Evolved at Their Own Quirky Pace

January 27th, 2011 01:10 admin View Comments

Welcome to the family of critters with sequenced genomes, orangutans. In Nature this week, scientists unveil the draft DNA sequencing of our great ape cousins—the only great apes that live exclusively in Asia.

The researchers assembled the draft genome of the female Sumatran orangutan (Pongo abelii) using a whole-genome “shotgun” strategy, an old-fashioned approach that cost about $20 million. In addition, the researchers gathered sequence data from five wild Sumatran orangutans and five Bornean orangutans (Pongo pygmaeus) using a faster and thousandfold cheaper next-generation platform. [LiveScience]

What did scientists find in there? For one thing, orangutans share about 97 percent of the their genome with humans, compared to the 99 percent we famously share with chimpanzees. The two orangutan species—inhabiting the Indonesian islands of Borneo and Sumatra—diverged about 400,000 years ago, lead author Devin Locke says. That’s much more recently than scientists had thought.

They also discovered that over the last 15 million years, orangutan DNA changed at a different rate than either ours or chimps’. Orangutans have undergone fewer mutations of the DNA, have a lower gene turnover rate, and have fewer duplicated DNA segments.

“That doesn’t mean the species itself has evolved more slowly, but that this particular mechanism of genome evolution has been proceeding at a lower rate,” Locke said. “Humans and chimps, in sharp contrast, have experienced an acceleration in this form of evolution over the past 5 million years or so.” [LiveScience]

That’s not the only peculiarity they found:

While in 2004 there were about only 7,000 Sumatran orangutans left in the wild, the researchers found that their population is actually much more genetically diverse than the 50,000 Bornean orangutans in the wild. Why the Sumatran orangutans are so much more genetically diverse is unknown. [USA Today]

As scientists use the new data to sort out the difference between the two remaining orangutan groups—and what their evolution says about all of us primates—they can simultaneously use it to figure out how best to protect them.

Knowing about their genetic diversity can help zoos and conservationists preserve and protect the species, Locke said. For instance, the Borneo and Sumatran species of orangutans should likely not be interbred, and genetically diverse populations are usually more likely to survive. In turn, the study has implications for human health. Inherited diseases are often linked to duplications in the DNA sequence that orangutans lack, Locke said. [Reuters]

Image: flickr / ltshears

Source: Orangutan Genome: The Orange Apes Evolved at Their Own Quirky Pace

Why Gorillas Play Tag: To Learn Social Etiquette and to Settle Scores

July 14th, 2010 07:51 admin View Comments

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].

Gorillas games, like their analogs in human kids’ games, would seem to play a role in social development and learning to play nice with each other. Gorillas strike each other pretty hard during play, Davila Ross says, but they’re careful not to strike too hard.

The game is thought to prepare gorillas for conflicts that might arise over food or mates. “This kind of playful behaviour lets them test their group members and learn what the borders are,” she added. “How far you can go with an individual is important for social interactions later in life” [The Guardian].

Davila Ross argues that gorilla tag is even more revealing than that. Those who are lower on the social ladder tend to be the instigators of the game, trying to get a leg up or an ego boost from besting a gorilla with more social status. Thus, she argues, the gorillas are aware of social inequities, and the competition of playing tag teaches them how to deal with unfair situations by seizing a competitive advantage, like smacking your friend and then running away.

“It remains unknown to what extent unequal play itself gives animals a more competitive edge,” the scientists write. But while further research will attack that question, one thing is clear: Humans probably wouldn’t fare well in an inter-species game of tag, as we wouldn’t describe the force with which they strike one another as “playful.”

Video: Davila Ross et. al.

Source: Why Gorillas Play Tag: To Learn Social Etiquette and to Settle Scores

Empathy Is For the Birds

June 30th, 2010 06:30 admin View Comments

grrlscientist writes “Common Ravens have been shown to express empathy towards a ‘friend’ or relative when they are distressed after an aggressive conflict — just like humans and chimpanzees do. But birds are very distant evolutionary relatives of Great Apes, so what does this similarity imply about the evolution of behavior?”

Source: Empathy Is For the Birds