Do you know that kangaroos have three vaginas?
Yeah you read that right.
It’s not just kangaroos, but also koalas, wombats and opossums - aka marsupials.
Marsupials are a group of mammals that have a pouch. What makes them so unique, is their ability to give birth to joeys the size of a jelly bean. These joeys then crawl up to their mother’s pouch where they attach to the teat for weeks or months until they are developed enough to start leaving the pouch. Giving birth is such a breeze for them - lucky bastards.
So how does this all tie in to their vaginas? Well, since male marsupials often have two-pronged penises, the side, or ‘lateral’ vaginas, carry the sperm to the two uteruses. What makes it even more complicated, is that the ureters which transport urine from the kidneys to the bladder, pass through the hole in the middle of the lateral vagina. So the lateral vaginas can’t fuse, or else the marsupial won’t be able to pee.
This then leaves us with the third vagina - the middle, or ‘medial’ vagina. The medial vagina is the birthing canal that the joey passes through. It has the benefit of providing the shortest path for the joey to travel through during live birth.
What’s fascinating is that the medial vagina is formed when the female becomes pregnant and remains as the third vagina for future births. For some species, the medial vagina will remain permanently open, while for others, it closes after birth.
While marsupials have such a complicated reproductive system, there’s the benefit of giving birth to a tiny jelly bean. And on top of that, pausing their pregnancy for more favourable conditions known as embryonic diapause. That’s a topic we’ll explore another time.
Why does nature have to be so NASTY