Apparently, their brains are just a little ring of cells that release amino acids and maybe have something to do with metabolism. The nervous system actually controls most things.
I don't know how they know to do this. Not even just instinct. But if a shrimp dies and eggs were already fertilized, they finish developing. I have seen babies coming up from the graveyard.
@stueytheround Life is a highly complex science experiment for me. 😄 My elementary school teachers would be so proud.