Why Gorilla Size Doesn’t Impact Genital Size: Unraveling the Mystery of Small Testicles and Low Sperm Count in Silverback Gorillas

JAKARTA – Being big and stocky is not a guarantee that genitalia will be proud of it. Case gorilla This is clear evidence that body size is not directly proportional to Mr. P.

Male silverback mountain gorillas can reach a height of 1.5-1.8 meters, with an arm span of up to 2.25 meters and a weight of 204-227 kg. However, his genitals were much smaller than expected, not more than 3 centimeters. This size is shorter than the penis of a newborn human baby.

Additionally, gorillas have small testicles, low sperm counts, and have low motility. A study published earlier this year in eLife revealed that gorilla sperm had very low mitochondrial function, slow swimming speed, and weak swimming power.

The study also explains that gorillas have a large proportion of non-motile and morphological sperm. This means that their reproductive abilities are limited compared to other species.

Why are gorillas genitals so small?

Reporting from JPost, researchers have identified the main reason for this. According to Susan Harvey, an expert writing in 2012 for UCL, the large size of the male gorilla is the reason why he has such a small penis.

Gorillas live in hierarchical and usually polygamous groups, where one dominant male has exclusive mating rights with all the females in the group. Harvey explained that when male competition is resolved through physical aggression, alpha males can secure their mating opportunities without the need for sperm competition.

“Smaller males have less access to females, so their reproductive success depends more on physical dominance than sexual competition,” he said.

This is very different from chimpanzees, who live in large groups of mixed sex where females can be with several males. In such groups, sperm competition is an important factor.

“Sperm can live up to four days after ejaculation, so when a woman is with two men in a row, the sperm from both men can compete directly,” Harvey said.