Giggling Gorillas, Chuckling Chimps

There were several neat articles this week about whether or not animals actually laugh. I got a real charge out of it – the idea that chimps chuckle when tickled, that even gorillas can guffaw – and then we got to the part where a cat’s purr is called a laugh, plus the claim that scientists had “proven” that laughter follows an evolutionary tree. That’s when my BOGUS-o-meter whinged into the red zone.

First, how do you quantitatively identify laughter in animals? Apparently you do so by defining a laugh based on what you believe is laughter, then by looking to see if it (oh what a surprise) exists in the very place where you defined it. For example, rats’ laughter was defined as panting – because they pant when they’re young, running around chasing each other. Then, wow, oh shock, young rats are “proven” to laugh. Hmm, does anyone else see a flaw here?

Second, how do you definitively state laughter follows an evolutionary tree? Apparently you do so by testing for laughter in one branch of species (let’s say mammals, based on your somewhat flawed definition of laughter), then by saying afterwards – see, there it is, it fits the evolutionary tree! Here’s the catch – how can you say it’s evolutionarily mapped, when you didn’t define (in however flawed a way) laughter among jellyfish? How about vocalization among spiders? Who’s tested a cobra? Or was it merely that the lab couldn’t find anyone to tickle some species for minimum wage?

These articles got a ton of media-time, including being prominently featured in the MSN Technology and Science section (and originally published in the august journal Science). The ape angle on the story was covered by Live Science, with its original article published in Current Biology. Heck, for your own joy habit, it’s worth going to the Live Science article purely to see the videotapes of chimps being tickled.

In contrast, sadly, the state of science reporting these days is no laughing matter…

Related articles by Zemanta

• Reconstructing the evolution of laughter in great apes and humans (biosingularity.wordpress.com)
• Our primate ancestors have been laughing for 10m years (guardian.co.uk)