Posted on 02/19/2006 12:18:49 PM PST by blam
Predators 'drove human evolution'
By Paul Rincon
BBC News science reporter, St Louis
The alternative view that man was the one hunted was suggested
The popular view of our ancient ancestors as hunters who conquered all in their way is wrong, researchers have told a major US science conference.
Instead, they say, early humans were on the menu for predatory beasts.
This may have driven humans to evolve increased levels of co-operation, according to their theory.
Despite humankind's considerable capacity for war and violence, we are highly sociable animals, according to anthropologists.
James Rilling at Emory University in Atlanta, US, has been using brain imaging techniques to investigate the biological mechanisms behind co-operation.
He has imaged the brains of people playing a game under experimental conditions that involved choosing between co-operation and non-co-operation.
From the parts of the brain that were activated during the game, he found that mutual co-operation is rewarding; people reacted negatively when partners did not co-operate.
Dr Rilling also discovered that his subjects seemed to have enhanced memory for those people that did not reciprocate in the experiment.
Man 'the hunted'
By contrast, our closest relatives - chimpanzees - have been shown not to come to the aid of others, even when it would pose no cost to themselves.
"Our intelligence, co-operation and many other features we have as modern humans developed from our attempts to out-smart the predator," said Robert Sussman of Washington University in St Louis.
According to the theory espoused by Professor Sussman, early humans evolved not as hunters but as prey for animals such as wild dogs, cats, hyenas, eagles and crocodiles.
He points to the example of one ape-like species thought to be ancestral to humans, Australopithecus afarensis.
A. afarensis was what is known as an "edge species"; it could live in trees and on the ground, and could take advantage of both.
"Primates that are edge species, even today, are basically prey species, not predators," Professor Sussman explained.
Hard target
Dr Agustin Fuentes at the University of Notre Dame agrees with the predation hypothesis.
He believes early humans were subject to several evolutionary pressures, including predation.
But he also thinks they were expending more energy at this time and that child-rearing became more demanding.
All these factors contributed to an emergence of sociable behaviour in hominids that made them harder targets for predators.
Dr Fuentes points to fossil evidence of predation in two different groups of humanlike species: Australopithecus and Paranthropus.
The latter group, it appears, could not adapt to pressures such as predation, and became extinct between one and 1.2 million years ago.
The scientists outlined their work at the American Association for the Advancement of Science annual meeting in St Louis,
Face it. You've caught your cats looking at you like, "I bet I could take you" or "my ancestors ate your ancestors, monkey boy, so you better be nice to me."
Remember, the folks we're talking about were about a meter tall full grown at the tallest. Fossil skulls of young australopithecines show predation by large birds of prey which could easily lift them and carry them away.
I'm going to have to bookmark that site. I'm a bit of an amateur paleozoologist...
How about Nutria?
People are eaten by crocodiles every year in Egypt. Crocs kill more people than sharks. Remember, in Northern Africa crocs stake out ALL available water sources. You either have to go to their watering hole, or you die of thirst. The trick is to spot them and keep them in view while you drink.
Predators eat other predators. Pigs are one of the most vicious omnivores in existence (humans are also omnivores). Pigs have forward-facing eyes to hunt rodents and other critters they eat, but they are still preyed upon by other predators.
Wow, all those were created 6000 years ago.. what a diverse
creation from a masterful artist.
According to my dictionary, tapirs are ungulates, and their closest living relatives are horses and rhinoceroses.
I saw a nature program about capybaras several years ago. Back when the Catholic Church didn't allow people to eat meat on Fridays, but fish was allowed, the local people decided that the capybara was a fish because it spends so much time in the water...so they could eat it on Fridays.
Wowzer! I thought I'd been around a while.
They must not post very often.
"So far, in my experience, it's always been the other way around..."
Heh. I was waiting for someone to post that....
There are images of Alexander (the Great) hunting with his father, Philip. They were hunting lions -- in the Balkans. So yes, cats were a threat.
I think that medical malpractice insurance premiums are driving this development more than evolution. ;)
snicker.
Naked, clawless, bi-pedal, weaklings on the savana were prey; no mystery there. The mystery is what kind of co-operation would have resulted in survival.
In the meantime, no one has explained how awareness of the divine and unseen contributed to survival.
(Actual date unknown)
The downloaded pictures are of a man who works for the US Forest Service in Alaska and his trophy bear.
He was out deer hunting last week when a large grizzly bear charged him from about 50 yards away. The guy emptied his 7mm Magnum semi-automatic rifle into the bear and it dropped a few feet from him. The big bear was still alive so he reloaded and shot it several times in the head.
The bear was just over one thousand six hundred pounds It stood 12' 6" high at the shoulder, 14' to the top of his head. It's the largest grizzly bear ever recorded in the world. Of course, the Alaska Fish and Wildlife Commission did not let him keep it as a trophy, but the bear will be stuffed and mounted, and placed on display at the Anchorage airport to remind tourists of the risks involved when in the wild.
Based on the contents of the bears stomach, the Fish and Wildlife Commission established the bear had killed at least two humans in the past 72 hours including a missing hiker. The US Forest Service, backtracking from where the bear had originated, found the hiker's 38-caliber pistol emptied. Not far from the pistol was the remains of the hiker. The other body has not been found. Although the hiker fired six shots and managed to hit the grizzly with four shots (the Service ultimately found four 38 caliber slugs along with twelve 7mm slugs inside the bear's dead body), it only wounded the bear and probably angered it immensely. The bear killed the hiker an estimated two days prior to the bear's own death by the gun of the Forest Service worker.
Think about this: If you are an average size man; You would be level with the bear's navel when he stood upright. The bear would look you in the eye when it walked on all fours! To give additional perspective, consider that this particular bear, standing on its hind legs, could walk up to an average single story house and look over the roof, or walk up to a two story house and look in the bedroom windows.
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