Laughter is incredibly funny, and according to a BBC Health article, there are at least 10 things you didn’t know about laughter. Check them below.

1. Rats are ticklish too!

Want to see a rat laugh? Then tickle it. Rats laugh, chimps laugh, and so do dogs. But rats aren’t laughing at jokes. They laugh when they are playing, in the same way humans do, to show that they are happy and to encourage bonding. The rats that played more, laughed more. And the ones that laughed more preferred to be around other rats that laughed.

2. Laughter isn’t about jokes

We actually laugh most when talking to our friends. In fact we are 30 times more likely to laugh at something when we are with other people. Intriguingly, within these conversations, we are still not laughing at jokes: we laugh at statements and comments that do not seem to be anywhere near funny. It is a way to show people that we like them and that we understand them.

3. Your brain can tell the difference between deliberate and helpless laughter

When staged laughter was compared with real laughter, the brain could automatically tell the difference! But listening to staged laughter produces greater activity in an area called the anterior medial prefrontal cortex, which is known to be involved in understanding other people’s emotions.

It shows that we automatically try to understand why someone is laughing, even when not instructed to do so.

4. Laughter is contagious

Brain scans reveal that laughter is contagious. Even when someone is having their brain scanned  – which is not really very funny! – you can see their brain responding to the laughter by preparing their facial muscles to join in. And the more that someone shows a contagious response to laughter, the better they are at telling whether a laugh is real or forced.

This seems to suggest that joining in when you hear laughter is more than just contagion – it may be helping you to understand what that laughter means.

5. People you know are funnier

The fact that laughter encourages laughter is why an MC at a comedy club will spend a lot of time warming up the audience and keeping the energy high between acts. People find jokes funnier if they think they were told by a famous comedian.

6. Laughter doesn’t make you fitter

The internet is full of claims that laughter is great for your health. It’s sadly not true however that laughter burns more calories than going for a run.

Although laughing uses up energy, and increases heart rate by about 10-20%, you would have to laugh solidly for up to three hours to burn off a can of Pringles.

7. Relationships last longer when you laugh

When couples were asked o discuss something about their partner that annoyed them. The couples that used laughter and smiling, not only felt better immediately, but also reported higher levels of satisfaction in their relationship, and stayed together for longer.

This shows us that laughter is an emotion that we can use with those with whom we are emotionally close, to make ourselves feel better. This is critical to our enjoying a happy mood – but maybe even more important when circumstances are making us feel bad.

Laughter may help to measure not only the health of people, but also the relationships between people – a way of looking at our social interactions and the effects they have on us.

8. Laughter requires precise timing

In conversations, people time their laughter to occur very precisely at the ends of sentences. Even people speaking in sign language do this – despite the fact that they could laugh throughout their “silent” conversation if they wished to.

Kiri Pritchard-Mclean, a stand-up comedian who also teaches comedy, points out:

It takes a lot of confidence to stand on a stage and do nothing while the audience laugh – and it is hard to learn to come back in at the right point – not to trample on the laughter or wait too long and lose the momentum of the room.

9. Laughter is attractive

One study  found that we rate strangers as more attractive if they laugh at our jokes.

10. Some things are almost guaranteed to make you laugh

No comedian has found THE joke that’s universally and timelessly amusing.

But when trying to make people laugh, one of the best tools that work better than others are clips of people trying not to laugh in situations where laughter is highly inappropriate.