Seahorses

In seahorses it's the male that gets pregnant.

Seahorses are not horses in the pasture; they live in the sea.

Alongside cephalopods like the octopus and the cuttlefish, seahorses are some of the most fascinating animals in the ocean.

At the end of a gestation period usually lasting from two to four weeks, the pregnant male’s abdominal area begins to undulate rhythmically, and strong muscular contractions eject from a few dozen to as many as 1,000 fully formed baby seahorses into the surrounding water.

Other unusual characteristics of a seahorse are its upright stance, with its prehensile tail — which allows it to hold on to coral and other sea objects. Their tiny size, usually less than 15 centimeters, gives them a "jewel-like" appearance. And seahorses don't have the scales of typical fish; instead they have a dark, exo-skeleton of bony plates for protection and camouflage.

Seahorses are fish that don't look like, swim like, or reproduce like fish. With a head resembling that of a tiny horse, seahorses and their biological cousins, sea dragons, live in shallow tropical seas and temperate waters. One of the world's leading seahorse research laboratories, dedicated to breeding the fish, is located in the seemingly-unlikely setting of a busy inner harbor in Baltimore, Maryland. The city's National Aquarium and its nearby lab have already successfully bred 12 species of seahorses and have a new exhibit of the fish on display.

Seahorses feed on zooplankton.