Baby fish are orbiting Earth right now! The inner ear development of these Mozambique tilapia are being studied in zero gravity in order to figure out how balance develops. Fish inner ears are pretty similar to human inner ears, so perhaps free-floating fishies will give insight into balance and vertigo disorders.
Between being underground, on Mars, and in orbit, it’s an exciting time to be a tilapia! (Though I bet the ear-research fish meet much the same end as the fish-stick fish.)