How Pygmy Seahorses Hide in Plain Sight

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These masters of disguise are mysterious in so many ways — but they're slowly revealing their secrets. (Photo: Levent Konuk/ Shutterstock).

Which comes first: the home or the color of the seahorse? Scientists have raised this question about one of the most amazingly well camouflaged fish in the sea, the pygmy seahorse. This miniscule fish attaches to brightly colored fan corals and all but disappears from the sight of predators. But how do they manage to match their coral home so perfectly?

Researchers at California Academy of Sciences in San Francisco decided to find out the answer to whether a seahorse gets its color through its parents or through its environment. In other words, is a pygmy seahorse purple because its parents are purple, or is it purple because the coral on which it lives is purple?

Can a pygmy seahorse born to parents that look like this ...

pygmy seahorse on purple coral
Ethan Daniels/Shutterstock

... actually turn yellow if it makes its home in a yellow fan coral, and end up looking like this?

pygmy seahorse on yellow coral

First, researchers had to keep fan coral alive for at least three years. As KQED reports, this alone is a tough assignment, and since the species require fan coral to survive, it was a prerequisite to even being able to collect pygmy seahorses for study. Once they managed this, they were ready to collect a mating pair of pygmy seahorses from the wild. And this is what they discovered over the summer:

Amazed? We sure were. The research reveals so much about the species and how they are able to hide in plain sight. Pygmy seahorses might have the strict requirement of needing Gorgonian sea fans to survive, but the color of those sea fans is no issue for these experts in camouflage.

seahorse on orange coral
Eugene Sim/Shutterstock