Quick Take With sloths, the females are the ones responsible for mating calls. Three-toed sloth mating calls are often ...

From spraying mates with urine to changing one's sex, these are the most intriguing courtships in the animal kingdom.

For some animals, reproduction comes at the ultimate cost—their own lives. While this may seem extreme, it's a natural strategy to maximize reproductive success. These species invest everything into ...

What purpose does the penis serve? Why is it that members of one species have no penis at all, while those of another have two? Why do they vary so much in shape and size? And where do vaginas, or the ...

Animals may not celebrate Valentine’s Day, but courtship rituals, pair bonding and fierce competition shape love in the wild.

While millions of people are preparing to watch the total solar eclipse that will make its way across North America on Monday, the animals in that affected area — in homes, on farms, in zoos and in ...