In the rocky shorelines in the Pacific live strange, land-dwelling fish called leaping blennies. These 'walking fish' avoid being preyed upon by using camouflage, a latest research has found.
Pacific leaping blennies (Alticus arnoldorum) have always been a thing of curiosity. Other research has described them as Evolution in Action.
The University of New South Wales thought of getting a little close to these amazing 'land-fish' to understand their behavior, especially towards predators such as lizards and crabs.
"This terrestrial fish spends all of its adult life living on the rocks in the splash zone, hopping around defending its territory, feeding and courting mates. They offer a unique opportunity to discover in a living animal how the transition from water to the land has taken place," said Dr Terry Ord, of the UNSW School of Biological, Earth and Environmental Sciences.
For the study, researchers first looked at the color of five populations of the fish and compared it with their surroundings. They found that these fish perfectly matched their surroundings.
In another experiment, researchers made plasticine blennies and placed them on similar colored rocks or in sand. The test was designed to see whether or not camouflage lowered predation on these fish.
The team found that even after several weeks the fake fish on similar-colored rocks were intact while those on sand were torn into bits.
"This means the fish are uniquely camouflaged to their rocky environments and this helps them avoid being eaten by land predators," Dr Ord said in a news release.
Researchers also looked at the color of other related fish species and found that they matched with the blennies, suggesting that the ancestors of the fish had developed the unique coloration. The coloration helped blennies to survive out of water.
The study is published in the journal Animal Behaviour.
According to a research on blennies by S. Tonia Hsieh and colleagues, the fish leap by curling in to a C shape and then straightening out quickly.