Cuckoldry in fish

When fish lay eggs, the eggs need to be fertilized by sperm so that they can turn into new baby fish. The male fish usually releases sperm into the water, and the female fish swim through it to fertilize their eggs. But sometimes, sneaky male fish will try to fertilize eggs that aren't theirs. They might do this by waiting until the female fish lay their eggs, and then swimming over them and releasing their own sperm. This means that their sperm can fertilize some of the eggs, even though they didn't originally lay them.

This sneaky behavior is called cuckoldry. It's basically when one male fish tries to trick another male fish or female fish into raising his babies for him. This might sound mean, but in the fish world, it's a common strategy for males to try to pass on their genes without having to put in all the work of raising their own offspring.

When a male fish gets away with cuckoldry, it means that some of the eggs will be fertilized by his sperm instead of the female fish's usual mate's sperm. This can lead to a mix of offspring with genes from both the usual mate and the sneaky mate. In some cases, this can actually help the offspring survive better because they have a wider range of genetic traits to draw on.

So, to sum it up: cuckoldry in fish is when one male fish tries to fertilize eggs that aren't theirs, so that they can pass on their genes without having to raise their own offspring. It's a sneaky strategy that some fish use to try to gain an advantage in the competition to pass on their genes.