Did you know sharks can tan? And that they're resistant to melanoma, to boot?
Most fish can get melanoma from UV radiation, says DiscoveryNews, citing a study on skin cancer in wild fish populations published in PLos One.
But sharks seem to be the exception. Instead of getting cancer, sun-exposed sharks change from a brownish color to black, as found by the CSULB Sharklab in California.
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Contrary to popular belief, sharks do much more for humans than providing fodder for extremely violent action movies.
According to NOAA Fisheries, sharks position as an apex predator (at the top of the food chain) is essential to the balance of the marine ecosystem, preventing overpopulation in other species.
Sharks apparent resistance to disease could also help out human health researchers, as exemplified above, says National Geographic.
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However, it's a myth that sharks are impervious to cancer: it does happen to them, says Scientific American, and we don't even know if it happens less than in other species. (Sharks, as roaming ocean predators that are hard to keep in captivity, aren't exactly easy to study).
Unfortunately, the commonly-held belief that sharks are impervious to cancer has spawned an industry devoted to shark cartilage and other parts, driving down shark numbers in the wild and wrecking havoc on delicate marine ecosystems.
Bans on shark-fin soup, a popular Chinese delicacy rumored to have great health benefits, have taken effect in California, and a ban will begin in January in Chicago. Even China will stop serving the soup at official banquets, says CNN. (A recent study indicated that shark fins actually contain a potent neurotoxin, which is another good reason not to eat it).
Their interesting immune systems, however, are well worth further scientific study, adds Scientific American: they manage to protect themselves from disease without the assistance of bone marrow, which is where the vast majority of human immune cells come from.
Here's more on shark fin soup in China: