Sea turtles have evolved to use their flippers as hands, grasping jellyfish and even karate-chopping their prey, scientists have found.

Previously it was thought that the brains of the reptiles were too small to handle the dexterity required for manipulating objects with their limbs.

Instead, it was thought they simply used their flippers to swim and change direction.

But after scouring photos and videos of marine turtles, researchers at the Monterey Bay Aquarium in California have discovered the creatures are surprisingly nimble.

The images showed turtles karate-chopping and carrying jellyfish prey, rolling a scallop along the seafloor, grasping coral to eat the sponge clinging to its surface, and pushing against a reef for leverage while ripping loose an anemone.

In fact, the researchers identified at least eight different kinds of flipper manipulation, including ‘holding’, ‘digging’, ‘striking’, ‘tossing’, ‘leveraging’, ‘swiping’, ‘corralling’, and ‘pounding’. They were even seen licking their ‘fingers’ after eating.

Dr Kyle Van Houtan, science director at the Monterey Bay, who co-led the research, said: "Sea turtles don't have a developed frontal cortex, independent articulating digits or any social learning.

“And yet here we have them 'licking their fingers' just like a kid who does have all those tools.