Take a close look – a really close look – at Gorgonian corals in the Philippines, and you just might spot a pygmy seahorse. In this new video from Deep Look, we learn more about these incredible creatures and just how they manage such masterful disguises.

Smaller than a paper clip, the tiny animals are so well camouflaged that they weren't discovered by scientists until their coralline homes were brought into a lab in 1969.

A single Gorgonian (or sea fan) can host upwards of 20 pygmy seahorses, which will stay on the coral for their entire lives. The animals are covered in calcium-rich bumps, known as tubercles, that help them blend in with the sea fans' polyps. Two colour morphs exist in the wild: purple seahorses scattered with pinkish-red tubercles found on the coral Muricella plectana, and yellow seahorses with orange tubercles that prefer to hang around the similarly coloured Muricella paraplectana.

Scientists have long wondered whether these strange fish (yes, seahorses are fish) change their skin to match the Gorgonians they land on, or if they simply seek out the species of coral that matches their "outfit". To finally get to the bottom of this colouration conundrum, a team of scientists from the California Academy of Sciences (CAS) collected a breeding pair from a Philippines reef, and brought them back to the lab for a literal change of scenery.

"You never want to touch these sea horses," the team explains. "They're so small even that could hurt them."

The tiny haul was coaxed onto coral cuttings and amazingly, just 36 hours later, they were happily swimming in California, where they have been breeding up a storm ever since. "It's a pretty good indication that they like it here," the team adds. 

To test their colour-matching abilities, the babies from one brood were placed into two tanks, one with purple sea fans, and the other with orange. Much to the scientists' surprise, the animals developed differently depending on which tank they were in. 

But before you go into a squee-filled bout of "I want one!", you should know that pygmy seahorses do not do well in captivity. In fact, according to KQED Science, more people have walked on the moon than have seen a juvenile land on a sea fan. 

Aquariums that house pygmy seahorses have to constantly pump plankton through their tanks – not only for the animals themselves, but for the soft coral they live on. Gorgonians can't photosynthesise, and instead must feed on microscopic plankton as it passes by! Because of this, they also rely on a strong current to survive. 

The team raised their Gorgonians for three full years before attempting to collect the seahorses, just to make sure they had the process down. Talk about commitment to your work. You catch the collection process in action in the video below!

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Top header image: Klaus Stiefel/Flickr