The pygmy seahorse is covered with coral-like bumps and has a shortened snout, blending almost perfectly with its host and earning its title as an oceanic master of disguise. Scientists found that these remarkable traits are driven by genetic changes.

The pygmy seahorse has lost key genes controlling body size and craniofacial development, resulting in its tiny body and unique face. Skin genes evolved to match the coral's color and texture almost perfectly.

Gorgonian corals produce potent venom lethal to most creatures, yet the pygmy seahorse thrives. Its rapidly evolved nervous system genes likely help tolerate the coral's toxins, while the loss of certain immune genes allows it to rely on the coral's antimicrobial secretions.

Its strategy of "giving up costly functions and relying on a partner"—known as the Black Queen Hypothesis—shows that sometimes, losing is the key to survival.