Some insects have detachable penises, others produce sperm that is 20 times the size of their own body. Others have evolved with special equipment to help them tear rivals off potential mates. Insects can be creepy, promiscuous or murderous – but they are rarely dull. The stag beetle male – Europe’s largest beetle has huge jaws known as antlers designed for prising mating pairs apart. This behaviour is seen in numerous beetles, with horns of various shapes horns that have evolved to lever males off females. The Japanese rhinocerous beetle has a horn resembling a fork. Antlers are also used in …