Laughter’s seen as one of those things that makes us human, but behavioural scientists are identifying species around the world who share the habit of hilarity. Jamie Seidel finds out why it’s important from an evolutionary standpoint and its implications for the field of biology.
You’re a rat. In a lab. With people in odd white coats walking around you. It’s not funny! Or is it?
“Having a sense of humour would certainly help rehabilitate a heap of lab rats,” laughs PhD student of biological anthropology Sasha Winkler. “Rats are great. They have a rat laugh. If you tickle them, they make these high-pitched ultrasonic sounds.”
Not everything about Mother Nature is fight or flight. It turns out that many of our animal cousins find time for a chortle.
Take a walk in any urban park on a summer’s evening. You’ll almost certainly hear children giggling and screaming as they romp together.
But what’s that sound coming from the magpies cavorting under the sprinkler, or the funny noise being made by dogs gambolling over a ball? Could it be a chuckle? A guffaw? Or are we just superimposing our own expectations over what we observe?
“I think there’s enough evidence that we’re seeing other animals demonstrate social bonding signals, and they’re reflecting positive emotional signals,” says University of Melbourne animal welfare researcher Dr Mia Cobb.
“That sounds very scientific of me to describe it that way. But I don’t think it’s a stretch to call it laughing.”
A review of a multitude of animal behaviour studies from around the world by researchers at the University of California (UCLA), in the US, suggests that the natural world is full of laughter, identifying 65 different species as laughing candidates. There’s probably many more. We just don’t yet know what to listen for.
The best place to start is social play, says the study co-author, Sasha Winkler. At least, that’s where we’re most likely to confirm a cackle.
“Your pets probably aren’t laughing at you. Probably,” she says. “In humans, laughing at someone is a sort of passive-aggressive teasing behaviour. Finding ways to identify that in animals isn’t so easy.” But the concept of play, evident in many species, is something we can definitely relate to.
The meaning of mirth
“We’re not that special,” says Cobb. “Humans are just animals as well. So it makes a lot of sense that other highly social mammals will share a lot of the same feelings and behaviours.”
Great apes may have inherited a tendency to titter from the same ancestral source as us. They have a “play face” that looks like a smile.
Dogs may have picked up disarming humour from living beside humans for millennia. But the need to avoid misinterpreting play as pack politics has been around much longer than that.
“Dogs, when they’re play-bowing, are signalling ‘this isn’t serious … I might grab your neck – but I’m not trying to rip out your throat’,” says Cobb.
It’s a message reaffirmed by deliberate vocalisation.
“Dogs have a play growl that’s acoustically different to the growl they make when they’re aggressive,” Winkler says. “They also have a play-specific bark. So they have multiple ways to signal they want to start or continue to play.”
But is it really a laugh?
Anthropomorphism – the tendency to apply human traits to animals – is a risk.
“Dogs may be their own special case,” Winkler explains. “They’ve co-evolved with humans for so long that a lot of their facial features have been selected for how expressive they are. Their eyebrows, for example.”
But that’s where an animal behaviouralist’s comfort zone ends.
“For example, we’ve falsely attributed a guilty look to dogs,” says Cobb.
“It’s really an anticipation of our behaviour toward them. It’s appeasement. They can tell you’re about to get grumpy. Not necessarily why.”
We tend to make many such mistakes.
“The risk of anthropomorphising gets greater when it’s a distant species,” Winkler adds. “When cats make their playful purr, is that the same thing as laughter? I’m not sure.”
But she wants to know.
On a wing and a prayer
The UCLA study scoured dozens of research papers addressing animal play. Most examined physical behaviour. But among the notes and observations were buried references to unique sounds.
Some seemed obvious. Others less so.
“It was a Canadian researcher named Sergio Pellis who told us, ‘Hey, you’re missing how magpies have a call that they make during play’,” says Winkler.
The US study only found three birds showing such signs of joyous vocalisation – and all are antipodean: the Australian magpie, the budgerigar and New Zealand’s kea.
But do birds really want to have fun?
“A lot of scientists don’t think birds can play. But I do,” Winkler states. “You can watch a bird like a kea repeatedly rolling down a bank of snow with no obvious benefit beyond fun. They do it repeatedly. And they seem to be enjoying themselves.”
Cobb agrees. “You’ve got a highly sociable animal in the magpie, that we know lives in intergenerational groups. It sounds to me like it would make a lot of sense for them to have ways to bond and show those affiliative relationships among each other.”
The kea is a particular case in point. It has a specific call associated with fun. And when other keas hear that call over a speaker system, they spontaneously begin to frolic.
“They’re cheeky birds,” says Winkler. “Just hearing a kea’s warbling call makes others feel playful or puts them in a positive mood. It’s such a cool study. Not all animals have a response where the cause is so clearly tied to a playful vocalisation.”
Why magpies? Why keas?
“The common factor is how social they are.”
Parakeets also show signs of play. But are those cocky crows laughing at your misfortune?
“I wouldn’t mess with the corvids,” warns Cobb.
Despite the ubiquity of play in the animal kingdom, the evolutionary benefits aren’t clear.
Just among friends
“The ancient aspect of laughter, in its purest form, is what human babies give us,” says Cobb. “Even children who are born blind and deaf will laugh. So there’s certainly something innate about it.”
But it burns energy without immediate benefit. It distracts the participants. It attracts attention. Such a risk-reward equation doesn’t seem to add up.
“We argue in our paper that playful vocalisations – laughter – are likely to be quiet,” explains Winkler. “Most animals just want to signal to the willing partner they’re playing with. They don’t want attention from predators or others of their species.”
That appears to be the default condition. But then there are keas. And elephants. And humans. They laugh out loud.
“In these cases, we think there’s a group function for laughter. When you’re laughing with a friend, you’re broadcasting your friendship to others,” says Winkler. In humans, that signal can be complex.
“We’ve developed more recent uses for laughter that are complex – the derision or schadenfreude of getting some aspect of pleasure through watching others suffer or be excluded from a group,” Cobb says. “It’s not to say that animals don’t do that. But we haven’t explored that aspect yet.”
In humans, the message can carry profound meaning.
“There have been studies that show we can tell if a laugh is between old friends or if they’ve just met,” explains Winkler. “You can just imagine it, right? A sort of timid awkward laughter with someone you’ve just met versus a relaxed guffaw with someone you know well.”
So it seems logical that such subtlety also exists in the wild.
“I think there’s a lot of broadcast signalling going on in large social networks,” she adds. “Laughter is an important part of our social world.”
“Wouldn’t it be great if, instead of monitoring distress signals in commercial poultry sheds, we were monitoring how happy they sounded?” asks Cobb.
Animal welfare isn’t just about minimising harm and suffering. It’s about maximising positive emotional states.
“Laughter has fallen between the cracks,” Winkler says. “Animal behaviour studies historically have focused on negative behaviours and emotions.”
Tides are turning.
“There’s been a distinct change since I was doing undergraduate studies in zoology 22 years ago,” says Cobb. “The thought of being a canine welfare scientist wasn’t really on anyone’s radar back then.”
Perky pigs, sniggering sheep – laughter has some hefty ethical implications.
“If you know that pigs can have a rich and meaningful social life, that means they’re suffering when they’re held in restriction or isolated. So what might that mean for the bacon you like eating?” asks Cobb. “That’s a really uncomfortable thought for many people.”
As is the motivation behind studying laughter itself.
“I do feel that the motivation behind a lot of these studies has been rooted in how it can serve us,” Cobb adds. “I would love to see research that’s conducted with the ultimate goal of better understanding animals and how we can help them, rather than prioritising how we can better understand or serve ourselves.” After all, laughter tends to be contagious anyway. “Anything that brings groups together in a positive way is something we can all revel in.”
A comedy of global proportions
There’s still a possibility that magpie is howling at your feeble ground-locked existence.
Your dog may be sniggering with a friend over the way you fumbled that catch.
It’s just we have no way of knowing.
And then there’s our own insecure human nature.
“People have such a drive to anthropomorphise animals and to see human motives in them,” says Winkler. “If you do something embarrassing, you sort of look around to see if anyone saw you. And you see a bird in a tree, looking at you, making a clear call. Of course you pin your embarrassment on that bird. But it tells you more about yourself than the bird.”
Which is why it’s so important to identify a laugh as a laugh. And once a candidate laugh is identified, it can be tested.
The contagious effect of kea chortles is driving similar experiments among apes.
“We’re hoping to do some cognitive tests that measure their emotions, their optimistic bias,” Winkler says. “Animals, like people, tend to act more optimistically when in a positive mood. We’re hoping that will be one way to test for the cognitive effects of laughter.”
There’s little doubt real laughter exists among nature.
“It’s got to a point where we see so many similarities it would be almost negligent not to say yes, animals are experiencing these feelings in a way very similar to how we humans do,” says Cobb.
It’s now a matter of winning widespread acceptance of this concept.
“Through advances in neuroscience, we’re beginning to better understand our own thoughts and emotions,” says Winkler. “We know a reward circuit exists in human brains, for example. So we can look for it in mice and other animals. As human cognitive psychology and neuroscience advance, it opens up more opportunities to also look at animals.”
So, can we expect keas in MRI machines?
“Sure,” Winkler chuckles. “They’ve already trained dogs to hold their heads still and sit in an MRI. So many interesting things have come out of that. We’re starting to learn what they’re thinking when they look at what their owner is doing…”
Jamie Seidel is a freelance writer based in Adelaide.
Jamie Seidel is a freelance journalist based in Adelaide.
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