A green turtle swiping the stinging jellyfish (Cyanea barkeri) at Hook Island, Queensland, AustraliaCredit:Copyright Fujii et al. shared under Creative Commons CC BY “It shows an important aspect of evolution – that opportunities can shape adaptations.” 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. Three species were studied – the green turtle (Chelonia mydas), hawksbill (Eretmochelys imbricata), and loggerhead (Caretta caretta).Similar behaviour has been observed in marine mammals with flipper-like limbs such as walruses, seals, manatees and sea ottersBut the resourcefulness of the turtles was unexpected given the small size of their reptile brains.The findings, reported in the journal PeerJ, provide insights into the evolution of four-limbed sea creatures and raise questions about “nature or nurture” – which traits are learned and which are hard-wired from birth.Dr Van Houtan added: “We expect these things to happen with a highly intelligent, adaptive social animal. With sea turtles, it’s different. They never meet their parents; they’re never trained to forage by their mom.”It’s amazing that they’re figuring out how to do this without any apprenticing, and with flippers that aren’t well adapted for these tasks.”Lead author Jessica Fujii added: “Sea turtles’ limbs have evolved mostly for locomotion, not for manipulating prey.“But that they’re doing it anyway suggests that, even if it’s not the most efficient or effective way, it’s better than not using them at all.” Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.