Fun fact I like to share with everyone who enjoys shrimp. Up until the 90s 80s they were very difficult to breed in captivity. They just wouldn’t reproduce.
Until someone figured out that it you cut out one of their eyes, they will readily breed. Nobody really knows why, but they snip off one of the eye stalks on the females to get them to breed.
According to where I learned it, in high enough densities in concrete tanks, some shrimp would grind their own eyestalks off on the side of the tank. Some farmer put two and two together.