I can’t beat Science Nordic’s headline. They’re talking about some tragically vicious beetle anatomy:
The many spines on the penis are just as nasty, sharp and destructive as they look. And now a Swedish and American study shows that this is all deliberate.
The female beetle has no say in the matter
Armed with a laser, microscope and a penis pump, the researchers shaved spines off the beetles’ anaesthetised penises, and they can now reveal that the longer and more destructive the spines, the more success the male beetle has.
…
By dissecting the females after mating, the researchers could clearly see that the long spines cause severe damage and tear bleeding holes inside the female.
But why evolve such a cruel penis that hurts the female? It doesn’t appear to have much of an evolutionary advantage, yet the female beetles, strange as it may sound, are ready to mate again before a full day has passed.
…
“There’s no selection for gentler males,” says the Swedish professor.
”A gentler male wouldn’t really get his genes spread to future generations because he would have lower fertilisation success.”
Yeah, there are pictures up close and PERSONAL at the link.