A recent study has shed light on why human penises are significantly larger than those of our closest living relatives, chimpanzees. According to scientists, the change in penis size is believed to have occurred around four million years ago when humans began walking on two feet.
Professor Simon Underdown from Oxford Brookes University suggests that becoming bipedal made it physically harder for sperm to reach the cervix during sex, making conception more difficult and ultimately leading to the evolution of larger penises. In contrast, chimpanzees and other primates do not face this issue as they are not bipedal.
The pressure to transition to walking on two legs is believed to have been massive, allowing humans to hold and travel with tools, gain an advantage over rival species, and ultimately drive the evolution of human physical characteristics. However, Mark Maslin from University College London notes that the human penis is “extremely dull” compared to other primates, lacking features like lumps or ridges.
Interestingly, studies have shown that female satisfaction with a partner’s penis size can vary greatly. A survey of 1,400 women found that most would be satisfied with penises between six and eight inches long, while over half would be more likely to end a relationship if their partner had a too-large penis or was selfish in bed.
Furthermore, data has revealed that the average penis size in the UK has grown by 10% in just two years, putting it in eighth place globally for growth. However, Britain’s men still rank among the smaller in terms of overall size, with the Sudanese having significantly larger penises on average.
Source: https://www.the-sun.com/tech/13330153/reason-human-penis-size-big-gorilla