Washington: A new research has found that small prey fish are capable of growing a bigger `eye` on their rear fins to distract their predators and thereby dramatically boosting their chances of survival.
Researchers from Australia`s ARC Centre of Excellence for Coral Reef Studies (CoECRS) found that when constantly threatened with being eaten, small damsel fish not only grow a larger false `eye spot` near their tail - but also reduce the size of their real eyes.
Oona Lonnstedt, a graduate student at CoECRS and James Cook University, said that the result is a fish that looks like it is heading in the opposite direction - potentially confusing predatory fish with plans to gobble them up.
She said that it is an amazing feat of cunning for a tiny fish.
Lonnstedt said that young damsel fish are pale yellow in colour and have this distinctive black circular `eye` marking towards their tail, which fades as they mature.
She explained that they found that when young damsel fish were placed in a specially built tank where they were able to see and smell predatory fish without being attacked, they began growing a bigger eye spot, and their real eye became relatively smaller, compared with damsels exposed only to herbivorous fish, or isolated ones.
When the researchers investigated what happens in nature on a coral reef with lots of predators, they found that juvenile damsel fish with enlarged eye spots had an amazing five times the survival rate of fish with a normal-sized spot.
The team also noted that when placed in proximity to a predator the young damsel fish also adopted other protective behaviours and features, which included reducing activity levels, taking refuge more often and developing a chunkier body shape less easy for a predator to swallow.
The findings have been published in the journal Scientific Reports.