Until death does them part. Seahorses are extremely loyal couples. During the periods of reproduction and birth, couples of seahorses seduce each other during an underwater ballet. They swim side by side, face each other from head to head, twirl together around a blade of grass, and end up holding each other by the tails to seal their union. Throughout its life, the male seahorse will only accept eggs from its female, and the female will only give eggs to the same male. Photo credit: Romain Guy