Wild Gorillas using Tools

In Brazil, clever capuchin monkeys use heavy rocks to crack open nuts for food. NATURE's DEEP JUNGLE: THE BEAST WITHIN marks the first time the behavior has been captured on film. Tool use, which was previously thought to be a skill only of primates -- humans and chimps -- reminds us that human abilities arose long before the evolution of our species.

Tool use, which was previously thought to be a skill only of primates -- humans and chimps

Now, if you hear one say "nevermore" ....

Sarah Brosnan had long marveled at the apparent generosity of the capuchin monkeys she studies at Yerkes National Primate Research Institute in Atlanta, where the animals live in two large and highly social colonies. If Brosnan left a bowl of food within reach of one capuchin but not another”separating them with a mesh partition”the first invariably shared by passing food through the divider.As an anthropologist, Brosnan has a special interest in the roots of such behavior, specifically in mechanisms that encourage humans to cooperate when they receive no immediate benefit. Is the Golden Rule something we learn, or might it stem from an instinctual sense of fair play that we share with other primates?At Yerkes, Brosnan designed an experiment to explore the question. First, she taught the monkeys a bartering game: She would hand one of them a small stone, then offer it a grape or a cucumber slice in trade. The capuchins eagerly bartered for either treat, though they clearly preferred the sweeter fare.Next, Brosnan began giving one capuchin a grape, offering its partner a cucumber. The monkeys’ reaction to such unequal treatment could only be described as outrage, says Brosnan. “They’d literally throw their cucumber slices at me, something I’d never seen in all the years I worked with them.” The capuchins reacted even more negatively if they witnessed another receive the preferred treat for less work”if Brosnan handed their partner a grape, for example, without receiving a token exchange. In that situation, those offered cucumbers often threw away their stones or turned their backs on the scientist.“People often turn down a reward because it’s not what they think is fair,” notes Brosnan. “Such self-defeating behavior may not seem rational, but our research suggests it traces to the kind of emotional sense of fairness that may promote the high level of cooperation needed in species that hunt or otherwise work closely together.”

Jar writes:I had a 70 mile each way commute, almost all straight interstate, I-95. I got to see many interesting things.Grackles would run into the lane and drop food, usually nuts but also shellfish. Then they'd run back to the shoulder and face traffic. They never seemed to go any further than necessary.The Red Wing Blackbirds dropped stuff in front of traffic, the swooped down to get the bounty. Then they'd run off to the side with it.

An infant gorilla in a Congo sanctuary is smashing palm nuts between two rocks to extract oil, surprising and intriguing scientists who say they have much to learn about what gorillas can do - and about what that says about evolution.It had been thought that the premeditated use of stones and sticks to accomplish a task like cracking nuts was restricted to humans and the smaller, more agile chimpanzees. Then in late September, keepers at a Dian Fossey Gorilla Fund International sanctuary in this eastern Congo city saw 2 1/2-year-old female gorilla Itebero smashing palm nuts between rocks in the "hammer and anvil" technique, considered among the most complex tool use behaviors.In an e-mail message Monday from the Republic of Congo's Nouabale-Ndoki National Park, Breuer said that in 10 years of observation, his team had seen only two instances of tool use among gorillas - in one a stick was used to test the depth of a pond and in another a small tree trunk was used for support and as a bridge.Breuer said it was difficult to compare the behaviors his team had seen in the wild with the more complex behavior exhibited by Itebero, who had had contact with humans. But Breuer said Itebero's action "clearly shows that gorillas have the capability to use sophisticated tools even if they do not - or rarely - do this.""Very often the use of tools is triggered by certain needs and it seems that gorillas have only little needs to use tools in the wild," Breuer said.