It turns out that beauty has its (considerable) biological price. According to a new study published in Proceedings of the Royal Society B, primates with more attractive features usually have less testicles than others.
High sexual competition has led to the emergence of many “sexual jewelry” among male primates. These include the front flanges of orangutans, exaggerated noses of proboscis monkeys and even a beard of a man – all of them are designed to attract females. Such features can also cover the presence of extremely small genitalia.
Researchers found a marked correlation among 103 primate species (yes, including humans) between visual appeal and testicle size.
And what’s the reason?
The main assumption of scientists is that the possession of functions that make us more attractive, takes a lot of energy. Biologically expensive to produce these perfect cheekbones, symmetrical faces, complex and bright beards, and so on. And at the same time expensive to produce large testicles. So this is a compromise. Since both of these functions — attractiveness or the presence of large testicles — can contribute to your success in the birth of offspring, you only need one of them to do the work.
This means that males with larger testicles probably fertilize the few females with which they have a chance more effectively. In other words, size matters to less attractive men.