Hunting chimps may change view of human evolution

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Hunting chimps may change view of human evolution

http://news.yahoo.com/s/nm/20070222/sc_nm/chimps_hunting_dc

WASHINGTON (Reuters) - Chimpanzees have been seen using spears to hunt bush babies, U.S. researchers said on Thursday in a study that demonstrates a whole new level of tool use and planning by our closest living relatives.
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Perhaps even more intriguing, it was only the females who fashioned and used the wooden spears, Jill Pruetz and Paco Bertolani of Iowa State University reported.

Bertolani saw an adolescent female chimp use a spear to stab a bush baby as it slept in a tree hollow, pull it out and eat it.

Pruetz and Bertolani, now at Cambridge University in Britain, had been watching the Fongoli community of savanna-dwelling chimpanzees in southeastern Senegal.

The chimps apparently had to invent new ways to gather food because they live in an unusual area for their species, the researchers report in the journal Current Biology.

"This is just an innovative way of having to make up for a pretty harsh environment," Pruetz said in a telephone interview. The chimps must come down from trees to gather food and rest in dry caves during the hot season.

"It is similar to what we say about early hominids that lived maybe 6 million years ago and were basically the precursors to humans."

Chimpanzees are genetically the closest living relatives to human beings, sharing more than 98 percent of our DNA. Scientists believe the precursors to chimps and humans split off from a common ancestor about 7 million years ago.

Chimps are known to use tools to crack open nuts and fish for termites. Some birds use tools, as do other animals such as gorillas, orangutans and even naked mole rats.

But the sophisticated use of a tool to hunt with had never been seen.

Pruetz thought it was a fluke when Bertolani saw the adolescent female hunt and kill the bush baby, a tiny nocturnal primate.

But then she saw almost the same thing. "I saw the behavior over the course of 19 days almost daily," she said.

PLANNING AND FORESIGHT

The chimps choose a branch, strip it of leaves and twigs, trim it down to a stable size and then chew the ends to a point. Then they use it to stab into holes where bush babies might be sleeping.

It is not a highly successful method of hunting. They only ever saw one chimpanzee succeed in getting a bush baby once. The apes mostly eat fruit, bark and legumes.

Part of the problem is this group of chimps is shy of humans, and the females, who seem to do most of this type of hunting, are especially wary. "I am willing to bet the females do it even more than we have seen," she said.

Pruetz noted that male chimps never used the spears. She believes the males use their greater strength and size to grab food and kill prey more easily, so the females must come up with other methods.

"That to me was just as intriguing if not even more so," Pruetz said.

The spear-hunting occurred when the group was foraging together, again unchimplike behavior that might produce more competition between males and females, she said.

Maybe females invented weapons for hunting, Pruetz said.

"The observation that individuals hunting with tools include females and immature chimpanzees suggests that we should rethink traditional explanations for the evolution of such behavior in our own lineage," she concluded in her paper.

"The multiple steps taken by Fongoli chimpanzees in making tools to dispatch mammalian prey involve the kind of foresight and intellectual complexity that most likely typified early human relatives."

- Brian Sapient


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Very, very cool!!!  As

Very, very cool!!!

 As Penn Jillette like to famously quote, "Pops, they're so much like us" !!


American Atheist
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Cool! Thanks, Sapient!

Cool! Thanks, Sapient!


American Atheist
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Nice video.

Nice video.


healthy.addictions
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Chimps using weapons to KILL!

Well... kinda killing...Chimps seen making/using weapons for hunting.-Washington Post

Video of chimp using spear.

~~~~~~~~~~~~~~~~~~~~

For First Time, Chimps Seen Making Weapons for Hunting

By Rick WeissWashington Post Staff Writer
Friday, February 23, 2007; Page A01

Chimpanzees living in the West African savannah have been observed fashioning deadly spears from sticks and using the tools to hunt small mammals -- the first routine production of deadly weapons ever observed in animals other than humans.

The multistep spearmaking practice, documented by researchers in Senegal who spent years gaining the chimpanzees' trust, adds credence to the idea that human forebears fashioned similar tools millions of years ago.

 Bo is one of the chimps on the Senegal being studied by researchers, who recently discovered that chimps have the ability to make their own weapons to hunt small mammels. Bo is one of the chimps on a Senegal reservation being studied by researchers, who recently discovered that chimps have the ability to make their own weapons to hunt small mammels. (Paco Bertolani)

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Reserachers from a National Geographic-sponsored study discovered that chimps know how to use tools as weapons to hunt smaller mammels, a trait before now that scientists thought was only done by humans.

The landmark observation also supports the long-debated proposition that females -- the main makers and users of spears among the Senegalese chimps -- tend to be the innovators and creative problem solvers in primate culture.

Using their hands and teeth, the chimpanzees were repeatedly seen tearing the side branches off long, straight sticks, peeling back the bark and sharpening one end. Then, grasping the weapons in a "power grip," they jabbed them into tree-branch hollows where bush babies -- small, monkeylike mammals -- sleep during the day.

In one case, after repeated stabs, a chimpanzee removed the injured or dead animal and ate it, the researchers reported in yesterday's online issue of the journal Current Biology.

"It was really alarming how forceful it was," said lead researcher Jill D. Pruetz of Iowa State University, adding that it reminded her of the murderous shower scene in the Alfred Hitchcock movie "Psycho." "It was kind of scary."

The new observations are "stunning," said Craig Stanford, a primatologist and professor of anthropology at the University of Southern California. "Really fashioning a weapon to get food -- I'd say that's a first for any nonhuman animal."

Scientists have documented tool use among chimpanzees for decades, but the tools have been simple and used to extract food rather than to kill it. Some chimpanzees slide thin sticks or leaf blades into termite mounds, for example, to fish for the crawling morsels. Others crumple leaves and use them as sponges to sop drinking water from tree hollows.

But while a few chimpanzees have been observed throwing rocks -- perhaps with the goal of knocking prey unconscious, but perhaps simply as an expression of excitement -- and a few others have been known to swing simple clubs, only people have been known to craft tools expressly to hunt prey.

Pruetz and Paco Bertolani of the University of Cambridge made the observations near Kedougou in southeastern Senegal. Unlike other chimpanzee sites currently under study, which are forested, this site is mostly open savannah. That environment is very much like the one in which early humans evolved and is different enough from other sites to expect differences in chimpanzee behaviors.

Pruetz recalled the first time she saw a member of the 35-member troop trimming leaves and side branches off a branch it had broken off a tree.

"I just knew right away that she was making a tool," Pruetz said, adding that she suspected -- with some horror -- what it was for. But in that instance she was unable to follow the chimpanzee to see what she did with it. Eventually the researchers documented 22 instances of spearmaking and use, two-thirds of them involving females.


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For First Time, Chimps Seen Making Weapons for Hunting

In a typical sequence, the animal first discovered a deep tree hollow suitable for bush babies, which are nocturnal and weigh about half a pound. Then the chimp would break off a branch -- on average about two feet long, but up to twice that length -- trim it, sharpen it with its teeth, and poke it repeatedly into the hollow at a rate of about one or two jabs per second.

After every few jabs, the chimpanzee would sniff or lick the branch's tip, as though testing to see if it had caught anything.

 Bo is one of the chimps on the Senegal being studied by researchers, who recently discovered that chimps have the ability to make their own weapons to hunt small mammels. Bo is one of the chimps on a Senegal reservation being studied by researchers, who recently discovered that chimps have the ability to make their own weapons to hunt small mammels. (Paco Bertolani)

Video on the Web

Reserachers from a National Geographic-sponsored study discovered that chimps know how to use tools as weapons to hunt smaller mammels, a trait before now that scientists thought was only done by humans.

In only one of the 22 observations did a chimp get a bush baby. But that is reasonably efficient, Pruetz said, compared with standard chimpanzee hunting, which involves chasing a monkey or other prey, grabbing it by the tail and slamming its head against the ground.

In the successful bush-baby case, the chimpanzee, after using its sharpened stick, jumped on the hollow branch in the tree until it broke, exposing the limp bush baby, which the chimp then extracted. Whether the animal was dead or alive at that point was unclear, but it did not move or make any sound.

Chimpanzees are believed to offer a window on early human behavior, and many researchers have hoped that the animals -- humans' closest genetic cousins -- might reveal something about the earliest use of wooden tools.

Many suspect that the use of wooden tools far predates the use of stone tools -- remnants of which have been found dating from 2 1/2 million years ago. But because wood does not preserve well, the most ancient wooden spears ever found are only about 400,000 years old, leaving open the question of when such tools first came into use.

The discovery that some chimps today make wooden weapons supports the idea that early humans did too -- perhaps as much as 5 million years ago -- Stanford said.

Adrienne Zihlman, an anthropologist at the University of California at Santa Cruz, said the work supports other evidence that female chimps are more likely than males to use tools, are more proficient at it and are crucial to passing that cultural knowledge to others.

"Females are the teachers," Zihlman said, noting that juvenile chimps in Senegal were repeatedly seen watching their mothers make and hunt with spears.

Females "are efficient and innovative, they are problem solvers, they are curious," Zihlman said. And that makes sense, she added.

"They are pregnant or lactating or carrying a kid for most of their life," she said. "And they're supposed to be running around in the trees chasing prey?"

Frans B.M. de Waal, a primatologist at Emory University, said aggressive tool use is only the latest "uniquely human" behavior to be found to be less than unique.

"Such claims are getting old," he said. "With the present pace of discovery, they last a few decades at most."


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MrRage
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Oh, shit. Someone call

Oh, shit. Someone call Charlton Heston.


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Damn, dirty apes!

Damn, dirty apes!


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This is brilliant

This is brilliant

"Physical reality” isn’t some arbitrary demarcation. It is defined in terms of what we can systematically investigate, directly or not, by means of our senses. It is preposterous to assert that the process of systematic scientific reasoning arbitrarily excludes “non-physical explanations” because the very notion of “non-physical explanation” is contradictory.

-Me

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The FOX version of this is

The FOX version of this is titled "Killer Chimps Make Spears, Hunt Bushbabies"

How interesting even with science they have to use scare tactics... 


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Lol, yup.

Lol, yup.


Yellow_Number_Five
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Not really suprising.

Not really suprising. Chimps and other primates have been obseved to use tools in the past - I admit this is at a more sophisticated plain though.

The question here is, where did the behavior come from? Chimps are GREAT imitators - which is why they are so easily trained. Did these chimp learn to use spears on their own, or learn by observation of humans? It's interesting and important either way, but a question that needs to be sorted out. AFAIK chimps that use tools - be it rocks to smash nuts or twigs to catch termites need to be taught the behavior (be it by another chimp or a human cousin). Of couse this raises questions of where the behavior came from in the first place, if it originated in the chimps, and what the distinction would mean. But that's what the anthropologists are drueling over right now.

I am against religion because it teaches us to be satisfied with not understanding the world. - Richard Dawkins

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Yellow_Number_Five

Yellow_Number_Five wrote:

Not really suprising. Chimps and other primates have been obseved to use tools in the past - I admit this is at a more sophisticated plain though.

The question here is, where did the behavior come from? Chimps are GREAT imitators - which is why they are so easily trained. Did these chimp learn to use spears on their own, or learn by observation of humans? It's interesting and important either way, but a question that needs to be sorted out. AFAIK chimps that use tools - be it rocks to smash nuts or twigs to catch termites need to be taught the behavior (be it by another chimp or a human cousin). Of couse this raises questions of where the behavior came from in the first place, if it originated in the chimps, and what the distinction would mean. But that's what the anthropologists are drueling over right now.

 

Exactly: the big question, are these chimps imitating behavior, perhpas from humans? or was this learned by cognitive intuition?  Were they able to have foresight to be able to understand that a sharp object kills?  And what does this mean in their understanding of life and self consciousness?  It is interesting to see what other type of behavior is seen in other family groups.  I find this very intriguing. 

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