# A Probabilistic Model for Population Extinction

A Probabilistic Model for Population Extinction

A fluctuating organismic population can become extinct if its size drops below a certain threshold. This Demonstration simulates hypothetical life histories in which the population's random fluctuations have lognormal distributions, characterized by and , which terminate when the population size falls below this chosen critical number. The program records the extinction times and plots a histogram with a superimposed exponential distribution function having the same mean as the recorded extinction times. It also shows the quantile-quantile (q-q) plot used for testing the exponential distribution as a model.

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