For a long time it was believed that laughter was a uniquely human thing to do, but in 2009 scientists discovered something amazing. Laughter is actually an evolutionary response, and our ancestors were doing it as far back as ten million years ago.

The study, conducted by psychologists at Portsmouth University, found that if you tickle primates they laugh too. Chimpanzees, gorillas and other similar primates all make laughter like sounds when tickled, and produce similar sounds to express excitement, and during play.

Laughter is a strange expression. In some cases, humans laugh when they are happy or excited, but we also use laughter in other social contexts, such as to mock someone. Laughter as a biological response is something that many animals do, but social expressions are uniquely human. Interestingly enough, human laughter sounds rather different to laughter that is produced by apes. The reason for this is that humans laugh while they are exhaling, but chimps produce laughter while they breathe in. The sound of human laughter is created by regular vibrations in human vocal cords, while apes make laughing sounds from more irregular vibrations.

Laughter in Groups

Laughter as a social response is something that became commonplace as humans began to gather in bigger and bigger groups. Large groups are socially complex, and when a group includes ten or more individuals, the ability to talk and communicate effectively becomes increasingly important. Laughter is an extension of the ability to converse, and allows humans to signal that they are interested in participating in flowing, large group chats. This is an important part of the bonding process and something that helps the group as a whole flourish.

Laughter is also a form of release. It helps to get rid of excessive cortical excitation, and it is, in some cases, an involuntary response just like blushing and sneezing. Laughter is a complex and fascinating expression, and one that psychologists, social scientists and biologists have spent time investigating. From a scientific standpoint, we are beginning to understand the reason why laughter exists, but its importance as a bonding tool and a tool to improve our own wellbeing is something that we are just learning about. However, you do not need to be a scientist to understand that laughter is a good thing, and that people who laugh more are the best people to be around.