From Moving Freely to Stabbing the Opponent’s Abdomen, The Remarkable Evolution of Male Animal Traits

Two flexible, sometimes grasping, and spiky objects. Would you believe that these are all about the male reproductive organs of animals?

Since life emerged on Earth 4 billion years ago, animals have evolved and adapted repeatedly to survive. The diverse anatomies and behaviors of each animal have evolved strategically to adapt to their environments. Among them, one of the most diverse in shape is the reproductive organs.

In “Biology and Sex: The Mystery of Optimization Strategies” (authored by Emmanuel Puybaret, translated by Tsuneo Nishioka, published by Kyuryudo), astonishing reproductive activities of 32 species, ranging from crocodiles and ostriches to slugs and lice, along with the optimized male reproductive organs and sexual behaviors in various forms, are explained with vivid watercolor and delicate pencil illustrations. Here are some examples of astonishing reproductive organs from among them.

 

 

The “S. pacificus” can move freely and grasp objects!

The male reproductive organs of the Malayan tapir, which lives in Southeast Asia including the Malay Peninsula, can move like tentacles. Normally, the genitalia are folded like a bellows and stored inside the body, but when the time comes, they can move freely to explore the genitalia of their female partners. This movement is said to be a technique for seduction and reproduction.

 

More useful are the reproductive organs of the African elephant. The elephant’s genitalia, which can grow up to two meters long as an adult, can not only pick up branches and fruit, but can also stand up, swat flies away, and even scratch its belly. It is like a “second nose,” and these dexterous reproductive organs are extremely useful for mating with these 4-meter-tall, 6-ton giants. Incidentally, the female’s reproductive organs are also said to be 3 m long, so she may not be able to perform her duties unless she is able to do so.