Humour is a coping mechanism. Laughter is a stress or anxiety response. Men typically have to cope with their suffering via humour whereas women tend to have support networks.

Consider that, while out hunting, or while at war with another tribe, it was likely a man would see the most obscene and horrifying things. He'd see his friend disemboweled by a lion and would just have to live with that image, and making light of it was a way of dealing with that. I remember my great-great uncle was telling me a story about some war he was in, can't remember what, and he said that one of his friends stuck his head out of cover and immediately had the top half of his head blown off. My great-great uncle laughed a bit, then said "poor guy" and finished his story.

Humour is a coping mechanism. Women rarely have to cope with things the way men do. When a woman is upset, she is allowed to cry and be upset. Men just cope.