The Biggest of All
Blue whales have the largest penis of any animal — up to 10 feet long and weighing around 400 pounds.
The blue whale, the largest animal ever to exist on Earth, has reproductive anatomy to match. The penis of a blue whale can measure 8-10 feet long and weigh approximately 400 pounds.
But size isn't everything. Whale mating is remarkably challenging: - It happens in the water, where positioning is difficult - Whales have no arms to help with alignment - Females can be reluctant, leading to high-speed chases
Male blue whales have evolved a fibro-elastic penis that can change shape and search for the female's reproductive opening. The penis is hidden inside the body until needed, then emerges through a slit in the whale's underside.
Testes are also massive — each one can weigh over 100 pounds. Blue whales produce enormous quantities of sperm, though the reason isn't entirely clear since they don't seem to have the intense sperm competition seen in some whale species.
Despite their size, blue whale mating has rarely been observed and remains somewhat mysterious. What we do know comes from occasional sightings and anatomical studies. The entire mating process is thought to be quick — perhaps just a few seconds of actual copulation.