Does Size Matter? Let’s Ask the Anglerfish
Most of us have — as a result of poor decision-making or sheer chance — had to deal with clingy partners. Be that as it may, rest assured that life has not subjected you to anything worse than the fate of the female anglerfish in her pursuit for love. You might even wonder if it’s really love, when scientists like to call the phenomenon sexual parasitism.
It all originates in the weird size dynamics at play between male and female anglerfish of the Ceratioidei suborder. Females are large, with gaping mouths filled with rows of menacing teeth. Males are so tiny they’re among the smallest vertebrates known to man. It’s a mismatch made in heaven, technically known as extreme sexual dimorphism.

When males come of age, they use their well-developed sense of smell or acute eyesight to find a female. In fact, that seems to be the only task they put themselves up to in adulthood. On finding a female, the male anglerfish gloms onto her belly using specialized tooth-like structures called denticles. And once he gets a taste for her piscine ladyparts, the male literally never lets go.
After Mr. Anglerfish gets attached to now Mrs. Anglerfish, their tissues fuse and circulatory systems form links. As you’d imagine, the male relies on the female host for nutrition from that point on. It’s an easy life, if you’re a male anglerfish in a relationship.

Sex, despite the seemingly convenient arrangement, occurs externally. Each party shoots his or her gametes into the water synchronously to carry out fertilization. Not only do female anglerfish have no say in which males they mate with, they’ve also been known to host up to eight parasitic males at once. Females do have luminescent growths on their head to lure prey, though, so they have that going for them.
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