OceanDeep Sea
A male anglerfish merges with his mate. Permanently.
In several deep-sea anglerfish species the male, a fraction of the female's size, bites into her, fuses his tissue with hers and joins her bloodstream, wasting away into a permanent sperm-producing appendage. To pull this off without rejection, the fish have shed parts of the immune system every other vertebrate depends on.
Step by step
- In some anglerfish species the male is tiny — a fraction of the female's size.
- He bites her, his tissues fuse with hers, and their bloodstreams join.
- His organs waste away until he is a permanent, sperm-producing appendage.
- To avoid rejecting each other, these fish shed immune defences all other vertebrates need.
Source
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