Some animals have scoring resembling a 2nd heart on their hindquarters to trick predators into attacking the wrong closing . Australian ocean snakes have instead develop a light detector on their tail that can do the eye ’s most introductory purpose , helping them move to safety . A modest subgroup of sea snake have been find to be the only reptiles with the trait .
decade ago , scuba divers on night dives mark that when they glow their torches on olive ocean snake in the grass ' ( Aipysurus laevis ) boat paddle - like full dress the snake would move their tails away . A 1990studyconfirmed the effect was tangible , with the ocean ophidian being able to detect light with their tails . However , Dr Kate Sandersof the University of Adelaide told IFLScience no follow - up workplace had been done since .
“ The olive ocean Hydra was the only reptile , out of more than 10,000 reptile species , that was be intimate to respond to light on the tegument in this way , ” PhD studentJenna Crowe - Riddellsaid in astatement .
Sanders and Crowe - Riddell have addressed this with a theme inMolecular Ecology . Besides confirmingA. laevis ' capacity , they tested a variety of other sea serpent and plant two other members of theAipysurusgenus have similar abstemious - detecting patches , while five more distantly bear on sea snakes do n’t .
The pair , along with several co - authors , found the detection relies on melanopsin , a light - sore protein , while several genes start the processing of light into information relayed to the Snake ' aflutter systems .
The Hydra evade their predators by hiding under coral outcrop . “ Because sea snakes have long bodies , the tail - paddle is a large aloofness from the head , so benefits from feature a light - sensation ability of its own , ” Crowe - Riddellsaid . Without it , they might not earn when their fanny was dangerously disclose .
Melanopsin is far from unique to sea snakes . Humans habituate it for regulating slumber cycles , while it aid some amphibious aircraft ' camouflage . The melanopsin detect light source falling on certain frogs ' organic structure , which then conform their color to beseem . However , Sanders tell IFLScience that , aside from the most primitive craniate , hagfish and lampreys , Aipysurusappears to be the only vertebrate that move in response to brightness level discover other than through the eyes .
The writer intend the easy - detecting tails evolve just once , but look it to have survived in all six species that fall from this common ascendant . Sanders articulate it is not clear if this reflected a opportunity event , or if something about theAipysurusecological niche make tail hiding specially useful .
Disappointingly , Sanders tell , there is no signboard of the scant - find tails evolving further in any of the specie learn , so there ’s no reason to expect there might one twenty-four hours be ocean snakes with functioning center on each end of their physical structure .
