Deep-sea anglerfish have a very weird way of mating. Tiny males bite onto the much bigger females and in some species, his body tissues fuse with hers.
The male effectively turns into a sack of sperm hanging onto the female, ready for her to use whenever she needs to fertilise her eggs.
Female anglerfish even switch off parts of their immune systems, so their bodies won’t reject their male hitchhikers.
The strategy works in the vast, dark space of the deep sea, where if you encounter a suitable mate, it pays to hang on tight and never let them go.
This article is an answer to the question (asked by Peter Willis, via email) 'What's the weirdest way fish mate?'
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