Warning: the following post concerns the male gonads (testicles) and the creatures they are attached to.
Let’s start with bats. Bat testes range any where from .12% to 8.4% of body mass, the widest range of any group mammals (for comparison, primate testes range from .02% to .75% of body mass). Also, when many females are around, bat testes enlarge while the bat’s brain shrinks, and the reverse occurs when few females are around. What bats lack, however, is the distinction of largest testes in relation to body size. That belongs to the bush cricket. Male bush crickets have testes have testes that comprise a whopping 14% of their body mass. Finally we visit the ballsiest vertebrate in the world, not the one with the largest testes, or the strangest, but the most. Most animals tend to have two testes, many jawless fish have only one, but the animal with the most testicles is… the female anglerfish. That’s right. The FEMALE anglerfish. What happens is that female anglerfishes attract their tiny male counterparts which bite into her flesh and atrophy. After some time nothing is left of the males but their testes, producing sperm on-demand, and nothing keeps females from attracting more than one male. No, female anglerfishes have been found with upwards of six parasitic males, that’s more than twelve testes. This parasitic love makes the female anglerfish the ballsiest animal in the world.
Filed under Biology, Science