Why Evolution Made Us Laugh - Darwin Day lecture with Prof Jonathan Silvertown

Laughter is an odd behaviour if you stop to think about it. It’s involuntary and infectious. It starts in the cradle, well before the development of speech, but this innate behaviour blossoms into something that can bring a whole room into uproar. It is found in all cultures and, when heard, it is recognisable across boundaries of language. All these characteristics strongly suggest that laughter is hard-wired into the human psyche, which immediately conjures the favourite question of every evolutionary biologist: what good is it? And, we would add, why did laughter evolve in the first place.

Good jokes, bad jokes, clever jokes, dad jokes - the desire to laugh is universal. But why do we find some gags hilarious, whilst others fall flat? Why does explaining a joke make it less amusing rather than more so? Why is laughter contagious, and why did it evolve in the first place?