Fish are remarkably variable in size, shape, color and behavior, and our pacific sea horse (Hippocampus ingens) is one of the oddest. It is very rarely observed, but really has one of the most delightful parental care systems.
Believe it or not, it is the male sea horse that goes through gestation of the young! The female uses an organ called the ovipositor to deposit her eggs into the male's heat pouch, where they will be fertilized, incubated, hatched, and from where they will, in due course, emerge as miniature adults.