| Summary: | and the hare. In 1999, a month long study conducted by Dr. Greg Skomal found that these animals don’t spend all their time on the ocean floor (24) but often stalked the seal population with a presumably superior sense of smell as they navigated the cold waters (24). Another hunting mechanism the Greenland shark has tucked away in its arsenal is the same one that all species of shark possess: the amazing ability of electro-sensors. Electroreception is the ability to navigate and discern the Earth’s magnetic fields. It is comparable to echolocation with the ability to discern sound waves as means of hunting, similar to that of wales, dolphins, and bats. Our own sonar systems mimic this ability. Sharks however can read, for lack of a better word, the electro pulses that other animals and prey emanate (12, 17, 22 ). This is done by using an extra sensory organ housed along its snout in jelly-filled pores known as the Ampullae of Lorenzini, which are the little freckles or holes people see along the snout of sharks. Sharks are able to rely on this organ as well as others to hunt and capture their prey. In the case of the Greenland shark with its acute sense of smell accompanied by the Ampullae of Lorenzini, the lack of visibly may not be as damning. (22, 26) [illustration] This illustration maps out the pores that allow all sharks to sense the world around them on an electromagnet scale. (27) Marine species as a whole usually have long lives. From dolphins to whales to octopi, it is generally accepted that 250+ years is a perfectly natural life span; however, determining an actual age has been almost impossible in the past. It has been proven difficult to determine the age of sharks because with a vast majority we don’t even know where they reproduce or their population numbers, let alone how old they are. (17) The seemingly ideal scenario would be to put a shark in an aquarium and observe its life in a controlled environment. However, most sharks don’t survive long in captivity. Also, in captivity animals are fed on a regular basis, assuming they are willing to eat. A ten-foot tiger shark held in Florida’s Marineland in 1996 didn’t eat for five months after capture. Many such sharks die of starvation or engage in activities of self-harm like 34
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