Working at the Forefront
Lincoln Park Zoo’s role as conference host was boosted by the strength of
the Fisher Center’s chimpanzee cognitive-research programs. Research
projects currently underway to better understand chimpanzee behavior and
thought processes include the following:
Thinking with your Fingers
Behind the scenes at Regenstein Center for African Apes (RCAA), Ross is
conditioning some of the building’s chimpanzees and gorillas to use a
computer touch-screen in the hope that this interactive process will provide
an eventual window into the ape mind.
At the moment, the animals are still in the beginning stages, learning to
use the screen as a tool to make choices. The current research program
focuses on sequencing objects. Two choices are flashed randomly onto a
screen; if the participant touches them in the proper order, it receives a
reward in the form of a sugar-free jelly bean (tasty treats help to focus
the apes’ attention). As participants master the task, the computer ratchets
up the complexity, moving from two objects to three and so on. The goal of
the project isn’t only for the apes to handle each new task, however. Ross
also hopes that the time required to learn a new challenge will decrease
each round, demonstrating that the animals are gaining the cognitive tools
necessary for touch-screen mastery.
Those tools aren’t fully developed yet, though. While gorilla Rollie has
flourished, recently moving on to the sequencing of four objects, the
project’s other participants—chimpanzees Keo, Donna and Optimus and gorillas
Madini and Makari—are still working to master two. Still, Ross stresses that
the project has a long-term focus and that the eventual results should
provide a glimpse into the chimpanzee mind. “By training the apes to
interact with touch-screens, we’re hoping not to emphasize a single
task—i.e. sequencing—but rather to learn more about how they think and
learn. By developing their faculties with the touch-screen, we can provide
them with a platform to express their thoughts and preferences.”
The Right Tool for the Job
Researchers at the Fisher Center have a number of projects underway to
measure tool-use aptitude among gorillas and chimpanzees, but one of the
most impactful may be Ross’ nut-cracking project. By starting with a
relatively simple question—whether a chimpanzee can learn to use an aluminum “rock” to smash open nuts—the study may illuminate the trickier issues of
learning pathways and social transmission of knowledge in the species.
The project will proceed as follows: a single chimpanzee will enter an area
containing the nut-cracking apparatus (anchored to the ground to prevent the
primate from using it in less peaceful ways than cracking nuts). This
chimpanzee will watch videos of chimpanzees in Japan using a similar device
to open nuts. After the video has finished, other chimpanzees will be
introduced to the area, and scientists will monitor to see, first, whether
the chimpanzee that watched the videos learned the nut-cracking behavior,
and second, whether this knowledge is transmitted to the other members of
the group.
The information gained from the study could help researchers understand the
development of tool-use in the wild. As Ross says, “We know that chimpanzees
in the wild have diverse tool-using capabilities; they make use of branches,
leaves and rocks for tasks as diverse as feeding, drinking, grooming or
fighting. By attempting to simulate these behaviors in the lab, we can gain
a better understanding of how they originate in the field.”
A project with a similar goal that’s closer to completion is the Fisher
Center’s termite fishing study. Making use of the artificial termite mound
on display at RCAA, the project has tested the ability of the building’s
inhabitants to use twigs to access the treats (most often ketchup and
mustard) located within the mound. As the animals’ “fishing” skills develop,
keepers increase the degree of difficulty, moving from short tubes
containing the rewards to medium tubes, then long tubes and finally tubes
kinked at a 45-degree angle, which require the use of curved sticks by the
apes.
The species tested showed different aptitudes for the task. The chimpanzees,
known to use twigs to fish for real termites in the wild, were successful on
their first day of exposure and rapidly progressed through each of the more
difficult tubes. The gorillas’ success has been more limited, with a longer
learning curve and progress capped at the first, shorter tube.
Still, any evidence of tool use by gorillas is cause for excitement,
explains Lonsdorf. “We weren’t sure if the experiment would work: gorillas
don’t really use tools in the wild, and they’ve been neglected in
traditional cognitive research. There aren’t labs doing work with the
species, so everything we know comes from zoos. Gorilla cognitive research
really provides an opportunity for zoos to do some novel research, plumbing
the depths of the gorilla mind in comparison to more-studied species.”
While the Mind of the Chimpanzee Conference will focus solely on
chimpanzees, it holds similar potential for altering people’s perceptions of
how a species thinks. By gathering experts to illuminate the wide range of
chimpanzee cognitive abilities, it may raise larger questions about
humanity’s ethical responsibility for our closest living relatives.
“As studies convince a wider range of people that chimpanzees can not only
sequence objects, but that they have complex emotional lives, that they’re
similar to us cognitively, it may cause people to think about how we treat
them,” says Ross. “Ultimately, a better understanding of their cognitive
capabilities may lead us to a better understanding of their needs.”
