From The New Yorker
Now, imagine an animal that emerges every twelve years, like a cicada. According to the paleontologist Stephen J. Gould, in his essay “Of Bamboo, Cicadas, and the Economy of Adam Smith,” these kind of boom-and-bust population cycles can be devastating to creatures with a long development phase. Since most predators have a two-to-ten-year population cycle, the twelve-year cicadas would be a feast for any predator with a two-, three-, four-, or six-year cycle. By this reasoning, any cicada with a development span that is easily divisible by the smaller numbers of a predator’s population cycle is vulnerable.
Prime numbers, however, can only be divided by themselves and one; they cannot be evenly divided into smaller integers. Cicadas that emerge at prime-numbered year intervals, like the seventeen-year Brood II set to swarm the East Coast, would find themselves relatively immune to predator population cycles, since it is mathematically unlikely for a short-cycled predator to exist on the same cycle. In Gould’s example, a cicada that emerges every seventeen years and has a predator with a five-year life cycle will only face a peak predator population once every eighty-five (5 x 17) years, giving it an enormous advantage over less well-adapted cicadas.
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September 25, 2013 at 11:44 am
Hossein Akhtar Mohagheghi
You Never Can Divide Outputs Of The Equation (100X^2)+(160X)+(59) To Numbers (3,13,23,33,…) Or Numbers (7,17,27,37,47,57,…)
The All Outputs This Equation Are Prime Numbers Or Just Divide To Numbers (11,31,41,…) And Numbers (19,29,59,79,…)
With Selection Special Inputs To This Equation , Always We Can Have Prime Numbers In Outputs That For Sample If X is :
(2^27) or (2^97) or (2^267) or (2^287) or (2^797) or (2^1287) or (2^2817) or … Then All Outputs Is Prime Numbers.
Please Numbers To Note (27 , 287 , 2817 , …)
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