Because men were stereotypically more likely to do risky physical stuff. Especially if it's stupidly funny. But of course, that's less so now in many cultures, as women grow up feeling more freedom to Darwin out.
> Unintentional injuries are the #3 leading cause of death among men, but it is #6 for women. This is probably due to the fact that men are much more prone to saying things like, "Hold my beer, and watch this." Also, men tend to work in more dangerous professions where being killed on the job is a possibility.
What does manliness have to do with this?