STATES CHRONICLE – A species of squid has mismatched eyes which help it survive in oceans’ twilight zones. Scientists argue that there are a lot of creatures in the ocean which developed many strange features to make sure they are able to survive in dark and cold habitats. The cockeyed squid Histioteuthis heteropsis has a normal eye and a huge yellow one, probably having a strange vision.
Kate Thomas, a biologist at Duke University, argued that many specialists looked at this species and they have been long wondering how this squid can see. Thomas has observed this species trying to figure out more about its mismatched eyes and vision. She used more than 150 videos collected by the Monterey Bay Aquarium Research Institute (MBARI).
Thus, she was prone to obtain the first behavioral proof that the lopsided eyes of the squid developed to spot two distinct light sources which reach the depth of the sea. All these observations together with visual simulations suggested that the large eye was particularly adapted to look upwards, searching for enemies’ shadows against the fading sunlight. The small, normal eye was adapted to gaze downwards, searching for flashes of bioluminescence deep into the dark water.
Sonke Johnsen, a professor of biology at Duke University and also a senior author of the new study, pointed out that the deep sea is a natural lab for eye design. He explained that there certain types of eyes adapted to such a dark environment which can see bioluminescence and there are also other types of eyes which were designed to see the normal ambient light.
The results of the study are published online on February 13 in the Philosophical Transaction B magazine. This amazing species of squid is also known as the strawberry squid due to its appearance. It lives in the area of the ocean known as the twilight zone or the mesopelagic, located at 200 to 1000 meters under the surface of the ocean.
The light which managed to reach these depths is very faint. Sometimes, the bioluminescent flashes coming from other sea creatures tend to be shinier than sunlight. This species of sea creature was revealed about one hundred years ago. Since then, specialists have continuously wondering what this creature vision is like.
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