Two words: Rats laugh.

And studying them tells us a ton about why we do, too.

We’ll give you a minute to process this information. Yes, it’s true, rats do actually laugh. And studying them tells us a ton about why we do, too. But before we get to that, some quick Rat Facts™:

• Rat laughs are normally too high-pitched for us to hear. To study them, scientists had to modulate the recordings way down.
• Scientists found that rats laugh during rough-and-tumble play (AKA “playfighting”) and when tickled (AKA CUTE)
• They also found that rats laugh when they’re excited, or anticipating something joyful happening, like being fed (same, honestly).

Why were scientists studying rodent laughter in the first place?

Well, they noticed laughing is one of the most “animal” sounds we make… so they started to study non-human examples of laughter

While trying to understand how the brain processes emotions and social behavior, researchers Jaak Panksepp and Jeff Burgdorf found that these specific rat vocalizations were analogous to joy and laughter expressed by children during social play.

They also found that rats that could no longer laugh (such as those with damaged vocal cords) were more likely to be attacked or bitten while playing because they couldn’t let other rats know they were still “play fighting,” not real fighting.

Other chucklers in the wild include chimps, dolphins, and yes, dogs (when recordings of dog “laughter” were played for other pups, researchers noted, and we quote, “increased tail wagging” and other pro-social behavior).

Laughter isn’t just an involuntary noise

It can be, but we have to be super comfortable with someone to really let go and wheeze. In fact, most instances of laughing are social, or communicative. We’re much more likely to laugh with others than alone and we use “social” laughter to:

• Communicate that we’re non-threatening, as during play (think: the difference between texting a friend “I hate you” and “I hate you lol”)
• Comfort ourselves or others in uncomfortable situations
• Show that we want to connect with someone (in a study of 1000+ instances of laughter, speakers in a conversation were found to be “46% more likely to laugh than the listeners.”)

The Point: Think about the last time you really laughed with someone. Who were you with? What were you doing? How can you foster that same sense of safety and connection in your other relationships? It might be a simple as laughing at your co-worker’s dad joke…