We KNEW it.
One time I was crossing the intersection and a man came up to me, grabbed my breasts and said, "Nice milk-suckers," then went on his way. I was too stunned to do anything. Having someone physically grab your breasts may go beyond catcalling, but the intent is the same. Catcalling in many ways is verbal abuse, especially if it makes you feel uncomfortable.
According to an article on Medium, "Catcalling is mortifying at best; at worst it makes you want to pull someone's eyeballs out with your bare hands." Suffice to say, while some women like it and think of it as a confidence-booster, others find it rude.
Jacob Dunn, researcher of the recent study "Evolutionary Trade-Off between Vocal Tract and Testes Dimensions in Howler Monkeys," found that primates with louder roars have smaller testes and, consequently, less sperm. Trying to make a lot of noise or a lot of sperm at the same time just takes too much energy.
In the study, researchers used both new and published data on the larynx and testes size of 144 howler monkeys, using specimens from nine of the ten species collected in museums in the United States, Brazil, and Europe. For the new data, the researchers used laser surface scanning to produce 3D models of the hyoids (a U-shaped bone that supports the tongue and the larynx).
In addition, the researchers analyzed the frequencies of previously recorded howler monkey calls to confirm previous assumptions that hyoid size determines how deep and resonant the howls were.
The researchers found that there was a correlation between having a large hyoid and having the loudest roars, and there was a clear opposite relationship between the size of a monkey's hyoid and the size of their testes. In other words, the species who had the deeper calls had smaller balls.
"It may be that investment in developing a large vocal organ and roaring is so costly that there is simply not enough energy left to invest in testes," Dunn said.
So, the next time someone screams, "Nice ass" at you, you can always yell back, "Nice, barely-there balls!"