National Geographic : 2016 Jul
GREAT WHITE MYSTERY 91 famously mentioned in Jaws may have been perpetrated by a bull shark, not a great white. We don’t know for sure how long they live, how many months they gestate, when they reach maturity. No one has seen great whites mate or give birth. We don’t really know how many there are or where, exactly, they spend most of their lives. Imagine that a land animal the size of a pickup truck hunted along the coasts of Cali- fornia, South Africa, and Australia. Scientists would know every detail of its mating habits, migrations, and behavior after observing it in zoos, research facilities, perhaps even circuses. But the rules are different underwater. Great whites appear and disappear at will, making it nearly impossible to follow them in deep water. They refuse to live behind glass—in captivity some have starved themselves or slammed their heads against walls. (Several aquariums have released them for their own safety or because they were attacking tank-mates.) Yet scientists today, using state-of-the-art technologies, may be on the verge of answering two of the most vexing mysteries: How many are there, and where do they go? Unraveling these mysteries could be critical to deciding how to protect ourselves from them and them from us. When we finally see the great white clearly from all angles, will the world’s most fearsome killer deserve our fear or our pity? A large great white explodes through the water near the Neptune Islands. Scientists identify these sharks by their dorsal fins, their scars, and the jagged line separating their white and gray halves.