Experts from the Max-Planck Institute, in Germany, studied the mating practices of 249 human cultures and 34 animals.
They found that for many animals, having sex in front of the herd can spark rivalries, interfere with hunting or the raising of offspring in the social group.
Compared with human creatures, the overwhelming majority of people like to keep their sexual practice private.
Even those who fetishise ‘being caught’ or ‘being watched’ as a sexual pleasure need the conformist norm to be private. Otherwise, how do you know voyeurism exists.