| Summary: | carcharias, the Great White shark living at an estimated mere 75 years. In fact the universal average maximum age of sharks is 50 years in the wild. (In captivity that drops an average of 13+ years depending on species). The first captive great white shark was brought to the Okinawa Churaumi Aquarium in Japan in early January of last year. It died after only three days in captivity. Judging by its 11-foot (about 3.3 meter) stature, it was estimated to only be around three years of age. (20) Greenland sharks are a staple in Greenland, Iceland, Inuit and Nordic culture and cuisine. Although the meat of the Greenland shark is mildly poisonous, the natives discovered that if it is boiled in vinegar for a few days it becomes somewhat edible, but consuming it is not worth it unless one is massively desperate. (20) The earliest studies done on the Greenland shark were from the 1900’s. In those studies, fishermen began a yearly shark tagging experiment (in which the dorsal or tail fin of a shark is pierced with some manner of equipment to judge age, sex, longevity and migration) only to discover that the Greenland shark had been rumored by the locals to have a mysteriously long life (24). An article from Science magazine presenting findings from the University of Denmark says that “In the 1930s, a fisheries biologist in Greenland tagged more than 400 (sharks), only to discover that the sharks grow only about 1 centimeter a year, a sure sign that they’re in it for the long haul given how large they get.” Since they are roughly 7 meters in length, this takes a significant amount of time. In 2014, a female Great White was recorded off the coast of South Africa as being a recordbreaking eight meters long, completely discrediting the notion that the largest Great White stops growing after 4-7 meters. (20) What allows for this particular species to have such an incredible life span? Neilson and his colleagues determine that its environment must play role in the creature’s longevity. Cold water is theorized to slow down the animal’s growth (the Greenland shark only growing around a centimeter a year) as well as their biomechanical activity (4). A geneticist at the University of Michigan, Shawn Xu, postulates that perhaps its arctic environment is somehow slowing its metabolism. The basic hypothesis was that it simply lives its life in slow motion. However, recent studies on nematodes done by Dr. Xu proved that extreme cold can affect specific aging genes (29). The experiment showed that certain antiaging genes are activated when presented with a frigid environment that will allow for the nematodes to better fold proteins as well as rid themselves of DNA damaging molecules—both factors which might extend life. He suggests that this could easily explain what is going on within the Greenland sharks cells. (3) In connection to our own desire for an abnormally long life, this relates to the once farfetched notion of freezing humans in the hopes of 37
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