| Summary: | capabilities (13, 19). This gives scientists means to determine the longevity of ancient species of sharks, and by doing so they can compare the life longevity of modern and prehistoric species. However, new information discovered by lead scientist marine Biologist Julius Nielsen from the University of Copenhagen used carbon dating to determine the age of a specific female Greenland shark as well as 28 other individuals, and the results where incredible. The idea to resort to carbon dating came because the band theory proved useless since the specimen’s vertebrae had no rings to measure. Taking a leaf out of archeology’s book, the team decided to give carbon dating a try; this would only be applicable to fresh specimens, though, because without a fresh sample there is no true way to determine age as a result of bone structure— or lack thereof. Since carbon dating is the process of extracting DNA from fossilized material, the issue with carbon dating ancient sharks is that they do not have any fossilized bones to date. Apart from their teeth, the cartilage skeleton will completely brake down over time. A beautiful adaptation that these animals developed to conquer their environment leaves scientists very little to study. (2, 4, 10) Using the pulse carbon-14 method that was produced during the early 1950s, the team of scientists were able to determine the age of the animal by means of observing a heavy isotope left behind by American nuclear bomb testing. Noticing the abundance of carbon-14, the team concluded that they were actually looking through a window to the past. By examining the bomb pulse and seeing how this particular pollution had been introduced to the ecosystem in the early 50’s and had completely infiltrated these waters by the mid 60‘s, this proved that the inert anatomy developed at a particular time. For example, eye lenses will have an abundance of this element.(4) in many cases, nuclear radiation affects cell composition by weakening cell walls; it can also inhibit their functionality, causing all manner of problems for an organism. Because of this technique, the team was able to deduce that two of their specimens, both only 2.2 meters in length, were born in the 1960’s while a smaller individual was born in 1963. This proved that any animal that was considerably larger than the individuals born in the 60’s that did not have this elemental remanence would have been considerably older than the bomb blasts factoring in how slow these animals age. This resulted in the discovery that not only is this the slowest growing vertebrate in the world. It also concluded that they only reach sexual maturity at nearly 150 years of age, and, most intriguingly, that of the animals sampled, the oldest was carbon dated to be nearly 500 years old! (4). The next level of inquiry is what allows this particular species to have such an extended life span. Of the other 440 different species of shark, the only one that has any merit of longevity of life is the Carcharodon 36
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