Scientists were able to describe the cloaca, which included a fossilized piece of dinosaur poo, in detail for the first time.
Researchers confirmed that male kalutas are dying en masse after "intense" mating sessions driven by polyamorous females.
Male reproductive damage under heat wave conditions could be contributing to biodiversity declines in the Anthropocene.
A new study creates a red light district for flies.
Whale experts say the species could be reproductively extinct within 25 years.
Ducks are known for their bizarre corkscrew penises and complex vaginas.
Visitors flock to snake dens each spring in Manitoba, Canada to witness the snake orgies.
You filthy animals.
It's one of the first times that scientists have filmed “sneaking” in the wild.
Fighters have bigger horns, but lovers have bigger testicles.