Chimpanzees 'hunt using spears'
Chimpanzees in senegal have been observed making and using wooden spears to hunt other primates, according to a study in the journal current biology.
Researchers documented 22 cases of chimps fashioning tools to jab at smaller primates sheltering in cavities of hollow branches or tree trunks.
The report's authors, jill pruetz and paco bertolani, said the finding could have implications for human evolution.
Chimps had not been previously observed hunting other animals with tools.
Pruetz and bertolani made the discovery at their research site in fongoli, senegal, between march 2005 and july 2006.
"there were hints that this behaviour might occur, but it was one time at a different site," said jill pruetz, assistant professor of anthropology at iowa state university, us.
"while in senegal for the spring semester, I saw about 13 different hunting bouts. So it really is habitual."
Chimpanzees were observed jabbing the spears into hollow trunks or branches, over and over again. After the chimp removed the tool, it would frequently smell or lick it.
In the vast majority of cases, the chimps used the tools in the manner of a spear, not as probes. The researchers say they were using enough force to injure an animal that may have been hiding inside.
However, they did not photograph the behaviour, or capture it on film.
Senegal chimp image: iowa state university
Adolescent females exhibited the behaviour most frequently (image: m gaspersic)
In one case, pruetz and bertolani, from the leverhulme centre for human evolutionary studies in cambridge, uk, witnessed a chimpanzee extract a bushbaby with a spear.
In most cases, the fongoli chimpanzees carried out four or more steps to manufacture spears for hunting.
In all but one of the cases, chimps broke off a living branch to make their tool. They would then trim the side branches and leaves.
In a number of cases, chimps also trimmed the ends of the branch and stripped it of bark. Some chimps also sharpened the tip of the tool with their teeth.
Adult males have long been regarded as the hunters in chimp groups.
But the authors of the paper in current biology said females, particularly adolescent females, and young chimps in general were seen exhibiting this behaviour more frequently than adult males.
"it's classic in primates that when there is a new innovation, particularly in terms of tool use, the younger generations pick it up very quickly. The last ones to pick up are adults, mainly the males," said dr pruetz, who led the national geographic society-funded project.
This is because young chimps pick the skill up from their mothers, with whom they spend a lot of their time.
"it's a niche that males seem to ignore," dr pruetz told bbc news.
Many areas where chimpanzees live are also home to the red colobus monkey, which the chimps hunt. However, the senegal site is lacking in this species, so chimps may have needed to adopt a new hunting strategy to catch a different prey - bushbaby.
The authors conclude that their findings support a theory that females may have played a similarly important role in the evolution of tool technology among early humans."
I would source this but it is giving me a hard time with it. that was from bbc news though. im sure if you past the whole thing onto google itll show u.
So chimps are getting smarter. thats awesome. id like to give them some steel spear or teach them to use a rifle and see what happens!
Doesnt this somehow prove evolution?
Howcome it is giving me a hard time with links?
There are plenty of tool-using animals other than humans. A lot of these tool-users aren't even mammals.
One researcher built a vending machine for crows, which accepted coins and provided them with peanuts. The ROI on this device wasn't so great to warrant a crow vending machine franchise, but he did get quite a bit of lost change out of his invention.
Another researcher put a crow in a room, food in the bottom of a bottle, and a wire on the table by the bottle. The crow, unable to reach the food directly, managed to fashion a hook and get the food out of the bottom of the bottle.
Orangutans have been shown to write their speech-board symbols on the floor with chalk and on the ground with sticks. There's a TED talk dealing with this, and another about the crow tricks.
Wikipedia has a long list of wild animals which already use tools, no evolution by natural selection required!
yes..it does prove evolution
as do many other things
chimps using tools isnt unheard of though
theres been some using sticks to get grubs out of trees and things like that
also some of them can use tools...human tools...
not well of course but theyve learned from watching humans...as an expeirment though
of course, after time things evolve...they addapt to there surrounding enviroment
once they evolve from bashing clams against rocks, and using sticks, theyll start getting more advancesd...it just takes lots of time for that to heppen
Forgot to mention that technically it only proves that they are able to think better, not that they evolved. You have to see this in a neutral position, not in favor of Evolution or Creationism, to get the facts only... this study only proved what they were capable of doing. There is no physical or genetic proof that there was a change in their being.
Good example below..
"Out of the blue, their bacteria had abandoned Lenski's their glucose-only diet and had evolved a new way to eat"
it: did they really create a new way of eating, or just eating new things...
For For evolution: If their body was wired only to eat glucose and now are eating new things...
Against Evolution: Is there proof that their cells were not already prepared for new food however they just never at it...
On and on... but you see, we only want to get to facts.
That must be an interesting read... well, for an Anthropology Minor/ History major grad it is..
I don't think it proves evolution. Evolution refers to change in physical form by the means of natural selection. IT would prove Evolution if the study demonstrated that these particular Chimps have a bigger brain, which allows complex thinking abilities.
What this does prove is that the monkeys do not only rely on instincts. They have proven to have cognisant abilities. They understand their environment and are now able to control it to a certain extent. They may have stumbled upon this by accident / cause and effect.(Hey Mongo, that hurt, put that toy down... hey wait a minute...we can pick food with this...) or learned / taught behavior ( hey mongo look at those humans play with those sticks... did they just get some food?! lets try it!!) mothers and father s teach their offspring. It was done before with sweet potatoes.. a baboon learned that getting in the sea cleans her from dirt and mud (easy enough) ... she stuck his sweet potato to wash it. The baby saw her doing this over and over... Baby grows up and now likes Salty Sweet potatoes. Now the whole tribe likes them like that.
for all tense and purposes, Chimps are closest to man, in that they use tools. The main difference is that we create tools to make tools (we make rope to create a fa wooden / rope bridge. We build factories to make cars... the day the Chimp grabs a Stone as a hammer, brakes off a tree limb, and uses the tree limb in battle, we are equals - again for all tense and purposes. I understand we have complete languages and buildings, but you get the picture...
You don't "prove" evolution. Evolution, like any scientific theory, can be _disproven_, but not _proven_ (which implies no possibility of correction). You could claim that it provides evidence for evolution (which is sound), but I don't think you can say anything that bold given what's essentially a behavioural study without any firm biological evidence.
If you want to see an exciting development in evolutionary biology, though, take a look at this: http://scienceblogs.com/loom/2008/06/02/a_new_step_in_evolution.php
"Out of the blue, their bacteria had abandoned Lenski's their glucose-only diet and had evolved a new way to eat."