How do wild animal periods work?



Like imagine a Giselle bleeding out from their period in the wild, wouldn’t it be counterproductive to hide from predators? A lion can sniff blood from miles away so I imagine they’d have some sort of different reproductive method of expelling the uterine lining, or would they just not do it at all?

In: Biology

They don’t have periods like humans have. The stuff humans bleed out, animals have such a small amount of that compared to humans that the animals body absorbs it instead of shedding it out of the body.

Most mammals go into heat, but don’t have “periods” like humans do.

Wild mammals like cats (lions, tigers) will have faint bleeding, which will actually attract male cats for breeding, as menstrual blood smells much different than the blood of prey. The male cats know the smell and will flock to a female in heat to attempt to mate with them, they wouldn’t mistake that as prey or anything.

You’re right!

There are actually very few species that have a menstrual cycle. Most animals have an estrus cycle instead. Or heat. As in, most animals are only able to breed at certain times of the year – it could be once per year or twice per year or infinity times per year. During or following estrus, a lot of animals will bleed, but its not quite like with humans. And it’s not necessarily proportionate to humans. But keep in mind that estrus is usually accompanied by an incredible urge to mate… So most females of the species will be actively trying to get pregnant, which would negate the whole thing anyway.

Fun fact about estrus, there are a few animals whose estrus is actually triggered by mating. Rabbits, for example, become fertile in reaction to mating. Which means they’re essentially always potentially fertile or pregnant.

This might be slightly off topic, but what about animals that are capable of storing sperm?

I’ve read that in some reptile species, the female is capable of storing sperm for a year or more. One documentary I saw on African forest cobras, the female will store sperm after mating and will only “use it” once she finds a suitable location to lay her eggs. What triggers this?

If Giselle is bleeding during her cycle Tom Brady has to stay nearby to defend her as needed.