SCIENCE LAB SPECIAL : HOGFISH'S UNDYING VISION

 

Hogfish 'see' with their skin, even once they're dead : As a marine biologist, Lorian Schweikert knew hogfish could change color to match their surroundings.

But as an angler, she noticed something that wasn't in the textbooks : Hogfish can camouflage even when they're dead.

When Dr. Schweikert saw a hogfish with a conspicuous spearfishing hole through its body change color to match the texture of a boat's deck, '' it gave me this idea that the skin itself was 'seeing' the surrounding environment,'' she said.

Research by Dr. Schweikert and her team provides an explanation for hogfish blend into their background, even in the afterlife.

In a study published in Nature Communications, they identified a new type of cell deep in the hogfish's skin that might allow the fish not only to monitor its surroundings but also to edit its skin color.

Dr. Schweikert suspected that the hogfish's ability to camouflage while dead was just a quirk, that some part of the colour-changing system was taking a while to get the memo that it was a former fish.

Dr. Schweikert hoped the answer might lie in the arrangement of the cells in hogfish's skin. Her team used glowing antibodies to pinpoint the opsins, and transmission electron microscopy allowed them to peer into the cellular structures.

The image revealed that the opsins weren't on the surface of the skin, where they would have the best view of the outside world. 

Instead, they were beneath a layer of chromatophores - ''inkjet'' cells that produce a color change by expanding and contracting packets of pigment - and concentrated in a previously unknown cell type. [ Elizabeth Anne Brown ]