Have a Laugh

Scientists engaged in truly laughable research that took them around the world: investigating the laughter of apes. Psychologist Marina Davila Ross of Portsmouth University traveled to seven European zoos and a wildlife reserve on Borneo to record the sound apes made as their caretakers tickled them.

“In humans, laughing is a complex and intriguing expression. It can be the strongest way of expressing how much we are enjoying ourselves, but it can also be used in other contexts, like mocking,” Ross said. “I was interested in whether laughing had a pre-human basis, whether it emerged earlier on than we did.”

Ross’s team then used a computer program to analyze the recordings, a total of 21 taken from chimps, gorillas, orangutans, and bonobos—plus three from human babies. The software was designed to arrange the sounds in an “evolutionary tree” based on similarity. The laughter linked together in a way that matches the evolutionary tree: human laughter sounded closest to chimps and bonobos, farther from gorillas, and farthest from orangutans.

Of course, chimps and bonobos have already been identified as having more in common physiologically with humans than gorillas and orangutans; so, this shouldn’t be a big surprise. Moreover, the Guardian notes that “[h]uman laughter sounds very different from the noises produced by great apes,” a fact that the researchers ascribe to evolutionary changes after humans split from apes. Ape laughter often sounds more like a panting dog, a human asthma attack, or hyperventilation, according to the students of University of Maryland scientist Robert Provine, author of the book Laughter: A Scientific Investigation.

Even the physical and contextual causes of laughter differ. While humans laugh in sophisticated response to humor, apes may laugh when excited or aroused. And while humans laugh with only outward breaths, apes laugh during both inward and outward breaths.

As with other anatomical and behavioral features that humans have in common with animals, the commonality of laughter only supports evolution if one presupposes evolution, then interprets the similarity within that framework and previously established beliefs about human evolution.

Don’t believe us? Consider parrots: they are able to talk convincingly like humans, yet evolutionists aren’t looking for a human-bird “missing link,” since birds are supposedly descended from dinosaurs and only distantly related to humans (but then again, see this article).