Literally. Especially if you’re a deep sea anglerfish. You know – the scary looking bioluminescent fish from Finding Nemo? They look something like this:
Well, if you’re the female of certain taxa, not only can you grow up to 60 times larger than the males (sexual dimorphism in the extreme), but you also have to endure living with the ultimate couch potato. (Not to mention the fully justified “Yo mamma so fat…” jokes)
When scientists first discovered deep sea anglerfish they initially only recovered females, leading to theories on reproduction via some form of automixis. But then, noticing strange growths attached to many of the females, researchers eventually realized that the males were actually acting as sexual parasites.
Initially males are free living and display large eyes and olfactory organs, presumably for mate location. Males don’t reach full sexual maturity until they have found (and attached to) a female, and those unlucky in love die within a few months. Once a mate is located, the male attaches to the belly of the female using modified pincer-like denticles.
In those species with obligate parasitism, the initial attachment can be followed by the complete fusion of tissue between the male and female. As the male’s digestive organs shut down and he loses the ability to feed himself, the circulatory system of the two individuals can fuse and the female host provides nutrients via this new network of blood vessels. The male thus becomes permanently dependent of his female host (a little too much codependency maybe?).
Aren’t you ladies lucky the males of our species are only facultative parasites? But let this be a lesson: if you don’t stop picking the jobless, hard-drinking, unshaven, temperamental hard bodies over the gainfully employed, reserved, clean-cut, thoughtful dorks of the world one day you too will wake up with denticles in your belly. You think it was always like this for the anglerfish? No! A few short million years ago, they were all saying “I can change him…”
But it’s not all bad for the female, who actually can’t reach full fecundity until she’s been parasitized by a male. Some evidence suggests that the female is able to control the release of sperm from males (ahem) using hormones and the connected circulatory system, letting her fertilize eggs immediately after she lays them. Additionally, one female may play host to multiple males allowing for continual sperm manipulation and egg fertilization without having to first locate a mate.
Ridiculous reproduction or evolution just being efficient?