The #1 source for news about monkeys and apes

[Natasha Matza <nmmatza AT mac.com>]

> http://www.chicagotribune.com/features/chi-smart-gorillas-15- 
> oct15,0,703825.story

> Dumb gorillas need not apply
> Rollie, other apes at Lincoln Park Zoo show smarts in tests
>
> By William Mullen | Chicago Tribune reporter
> October 15, 2008
>
> Smarter than she looks
> <photo>
> Rollie, a female gorilla at Lincoln Park Zoo, is disproving the  
> conventional wisdom that gorillas are somewhat less intelligent than  
> their great ape cousins. (Tribune photo by Chris Walker / October 15,  
> 2008)
>
> When the frozen blueberry rolled out of a tube near a 42-inch  
> touch-screen computer in the Lincoln Park Zoo's great ape house, a  
> lowland gorilla named Rollie popped the berry into her mouth,  
> gleefully stomped her feet and let out a celebratory hoot.
>
> Rollie had correctly solved a seven-step number puzzle on the screen,  
> winning a treat and an enthusiastic cheer from a keeper. But her  
> skills are also being noticed outside the confines of the zoo.
>
> Conventional wisdom has it that gorillas are somewhat less intelligent  
> than their great ape cousins. Rollie's surprising success at her  
> morning research routine is challenging those assumptions, suggesting  
> she might in fact be faster on the uptake than chimpanzees and  
> orangutans. A report on her work recently caused a stir at the  
> biennial meeting of the International Primatological Society Congress  
> in Scotland.
>
> "Gorillas have always had a reputation of being a little bit  
> slower-witted than other great apes," said Steve Ross, who supervises  
> cognitive and behavioral research for the zoo's primate research arm,  
> the Lester E. Fisher Center for the Study and Conservation of Apes.  
> "They aren't as dynamic as chimps socially, and they don't show the  
> mechanical cleverness that orangutans display."
>
> Ross admits he subscribed to the theory himself.
>
> "This study can't generalize for all gorillas, but because [Rollie]  
> has been such a quick learner, it suggests that gorillas in general  
> are smarter than we have given them credit for," he said.
>
> Ross' immediate aim in studying primate cognition and intelligence is  
> to devise preference tests that allow animals to "talk" to keepers,  
> expressing what foods they like and don't like and reporting on good  
> and bad features of their habitats. But exploring animal cognition  
> also is a way of looking at the history of human intellect and  
> language, giving insights into how they evolved.
>
> Chimpanzees and orangutans are studied often at primate and medical  
> research laboratories worldwide. But captive gorillas—perhaps too  
> temperamental as adults to be used as research subjects—aren't often  
> kept outside of zoos, so they are far less studied.
>
> Lincoln Park, in fact, is the only place in the world that is doing  
> touch-screen testing with both chimps and gorillas.
>
> "It is exciting to see that [Rollie's] performance is comparable with  
> other great apes," said Tara Stoinski, a Zoo Atlanta primatologist.  
> "What is really exciting is to see this kind of work being done with  
> gorillas because so little research is being done on gorilla  
> cognition."
>
> Ross first started training some chimpanzees in 2005 to do tasks on a  
> touch-screen computer. He waited some months before training Rollie as  
> his first gorilla subject.
>
> At first, she merely had to touch the blank computer screen to get a  
> reward. Later, she would be rewarded only after touching a floating  
> numeral 1 about 2 inches high. When the number 2 was added, she was  
> not rewarded unless she touched the numbers in the right sequence.  
> Rollie can now touch the numbers 1 to 7 in order.
>
> Ross emphasizes that Rollie, age 12, is not counting.
>
> "This . . . is mastering the task of sequencing—categorizing—which is  
> an important cognitive skill that humans depend on," he said. "We  
> memorize sequences so that we can remember phone numbers, understand a  
> calendar or perform dance steps. The most important use of the skill  
> is language in which we learn the rules of syntax, what parts of  
> speech come first, second and third."
>
> The exercise Rollie works on is similar to one used elsewhere to test  
> other animal species that display high intelligence, including  
> pigeons, rhesus and capuchin monkeys, lemurs and chimps.
>
> Still, "there are some big differences in the research regimes," Ross  
> said. "A rhesus monkey in a lab setting might have 1,000 trials at a  
> time, while we have very limited time with our apes, doing 30 trials  
> at a time."
>
> The animals' motivation to perform varies too.
>
> "The testing period with the snack rewards may be the highlight of the  
> day for lab animals," Ross said. "In the zoo . . . our animals live  
> with families, friends and intergenerational companionship, [so] there  
> isn't as much motivation to learn a skill on a computer for token  
> rewards. That makes Rollie's performance all the more impressive."
>
> Thus far, she has outperformed Optimus, a 9-year-old male chimp being  
> measured in an identical test regimen.
>
> Ross has begun broadening his gorilla data by recruiting two other  
> apes for the computer exercises: Kwan, a regal 19-year-old male  
> silverback, and Azizi, an impish 4-year-old male who is showing signs  
> of being an even faster learner than Rollie.
>
> There are differences in style when gorillas and chimpanzees work the  
> computer, Ross said. Chimps, like humans, let their hand hover, index  
> finger extended, in front of the screen before touching the icon they  
> want. Gorillas use knuckles instead of fingers to touch, and their  
> hands sweep recklessly across the screen before striking the target.  
> Sometimes they accidentally swipe a wrong number on the way, aborting  
> the test.
>
> As a reward, chimps like sugarless, jelly bean-like Primatreats in  
> banana and piña colada flavors. But the first time Kwan smelled a  
> Primatreat, the gorilla threw it out of his cage. Gorillas prefer  
> frozen blueberries or dried pasta.
>
> And some animals, including Rollie, don't much care if they are  
> rewarded or not.
>
> "Rollie is a really motivated gorilla," Ross said. "All of the animals  
> participate willingly in the experiment, but Rollie seems to enjoy the  
> computer tasks so much, she will even do it without getting a food  
> reward, but just for the joy it gives her."
>
> wmullen AT tribune.com