Many giant squid eyes are as big as basketball. Even for animals with a body weight equivalent to five adults, this eye is also regarded as huge. Giant squid is similar to a large sailfish, but the former is 27 times larger than the latter's. Sank Johansson, a biologist at Duke University in the United States, said: “Giant squid and squid are similar in size, but according to proportions, the squid’s eyes are larger and its diameter and volume are 3 and 27 times that of the latter. The situation is unclear. The question is why this is so. Why do giant squid require such a large eye?" It is gratifying to note that the answer to this question is not that they are trying to track down and suppress fishing boats filled with frightened people. Johnson believes that The big eye of the giant catfish is to be able to see more clearly around it when it swims through the sea water and discover the imminent danger in time.