Tuesday December 20, 2011
Study to find out if apes can use tools
By NATALIE HENG
A researcher is looking to find out if orangutans’ understanding of tools extends to future use.
WHAT separates us from animals? Nick Mulcahy, a British researcher in comparative psychology from the University of Queensland in Australia says the answer to that question used to be: Humans are the only ones that use tools.
British primatologist Jane Goodall came along and dispelled that myth back in the 60s when she recorded chimpanzees not only using tools (twigs to fish termites out of mounds), but modifying them as well.
The goalpost has been shifting ever since. “After that, they said animals can’t use tool kits, but then recently someone found a chimpanzee using four different kinds of tools,” says Mulcahy.
One of the newer “humans are the only animals that can (fill in the blank)” answers to have emerged is: plan for the future.
The posit is controversial, however, and opinions in the scientific community are divided.
“The catchphrase is mental time travel,” explains Mulcahy. “This means you can mentally go back into the past and understand that you had a banana for breakfast.
“Then you can go into the future, and say on Thursday I will get apples and not bananas, anticipating Thursday is an apple day.”
It sounds simple, but many scientists think animals can’t do this.
Mulcahy became interested in ape cognition 11 years ago; his studies have today landed him in a search to find out whether those scientists are wrong.
Research he conducted with Josep Call, a well-known scientist in the field of primate cognition at Max Planck Institute in Leipzig, Germany, has previously shown that apes are able to learn how to save tools for future use.
When given a choice of keys, only one of which would provide access to a food-reward puzzle which they could see but had no access to at the time, many apes successfully learned that they had to save the correct key for later.
Could this be evidence for future planning?
“A criticism was that they were not thinking about the future but associated the tool with food because we trained them to.
“So now I am trying to show that they are actually thinking about the tool.”
Mulcahy has set up shop at Singapore Zoo, and will be travelling to Zoo Negara and Zoo Taiping to conduct more tests on orang-utans in the coming months.
His studies have taken him back and forth between South-East Asia and his current academic base in Australia.
Over the years he has watched some of his subjects, like Satria, a 14-year-old male orangutan, grow up.
“In my experiments right now, they have to not only save the tool, but also to look after it and protect it.
“This would show they know they will need it in a few hours, and have to be careful and take care of it. It would indicate they are not just keeping hold of it because for some reason it gets food and they don’t really know why.”
Mulcahy is secretive about the details of his experiments; however, he has his suspicions about whether animals can plan for the future.
“I’d be surprised if they don’t.”
Theory of mind
Another long-held assumption when it comes to filling in the blank is that animals don’t have a theory of mind, a concept that refers to one’s ability to attribute mental states to oneself and others.
These include states like belief, intent, knowledge or pretending, and the theory assumes someone with a theory of mind possesses an understanding that other people share such mental states, and that these may vary from their own.
The Sally-Anne test is a classic way to test for theory of mind in human children. A doll named Sally takes a marble and hides it in her basket and then “leaves the room”. Another doll named Anne then moves the marble, and puts it in her own box.
If a child has developed a theory of mind, they are expected to say Sally believes the marble is still in her own basket, demonstrating they understand the concept that people can have false beliefs. Up to a certain age, all children fail this test, implying that children eventually learn that others can hold false beliefs.
There are all kinds of variations of this test, some of which are designed to be used on animals.
But every ape fails them, according to Mulcahy.
This, however, doesn’t necessarily mean the apes don’t have a theory of mind. Mulcahy thinks it could just mean the experimental designs aren’t good enough.
“The biggest challenge is devising experiments, because you can’t ask an ape the same questions you ask a child.
“The biggest barrier is not having language to communicate.”
Mulcahy has in fact done research to show that apes previously failing tasks based on communicative cues such as pointing or gazing to an opaque container with rewards, began doing better once adjustments had been made to the experimental set-up.
And there is plenty of anecdotal evidence that apes might understand that people may know something from a perspective they cannot see.
“They follow your gaze, all apes follow your gaze, so what are they understanding about your gaze?
“Let’s say you’re looking at a door, but that’s not interesting them (people are always looking at doors).
“If they follow your gaze and see a board, however, they’ll go and have a look behind it, to see if there is something they’ve missed, and they’ll keep checking back on you.
“If you look at something obvious, they’re not interested, but if you look at something they can’t understand, they will go and explore.”
The theory of mind test is one of the hardest tests for an animal, but Mulcahy hasn’t entirely closed the door on that just yet.
He says that at least research on ape cognition over the years has shown people there is a lot of interesting stuff happening just below the surface.
Why ape cognition matters
It was a chance encounter of comparative psychology, a branch of psychology which compares the similarities and differences among species to gain an understanding of evolutionary relationships, that first got Mulcahy hooked.
In fact, all those years ago he’d started off studying evolutionary psychology and human behaviour, before deciding that animal behaviour was far more interesting.
“It’s fascinating because of what it can tell us about ourselves.
“Working out the differences between apes and humans helps us understand how we have evolved differently, and why we are so intelligent compared to other animals.
“Going to space, we understand a lot about the universe, a lot of people say we are very clever and we are, but no one really understands where that came from.”
Studies that contribute to public awareness on just how intelligent other species are may also be pivotal in getting people to value them.
Empathy, stemming from the idea that species such as the orangutan may be capable of the same pain or emotional hurt that we feel in response to their external environment example, may be important in getting people to feel more strongly about conservation issues.
On his contributions to comparative psychology, Mulcahy does it out of passion.
“I wake up in the morning and think, I have the perfect job. I go to sleep some nights when the experiments are going really well and think to myself, how are they going to do tomorrow?
“Are they going to pass?”
As for the apes, the experiments are a form of enrichment for them.
“If they don’t want to participate, they don’t have to, but they love playing the game because they get grapes.
“I haven’t had a refusal yet, it’s a challenge to them. They sit there and they have to figure out how to get this grape. They’ll sit there for hours, and if they get bored they just go away.”