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Monte Carlo modeling of the effect of extreme events on the extinction dynamics of animal species with 2-year life cycles

Sukanto Bhattacharya·Sreepurna Malakar
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Abstract

Our paper computationally explores the extinction dynamics of an animal species effected by a sudden spike in mortality due to an extreme event. In our study, the animal species has a 2-year life cycle and is endowed with a high survival probability under normal circumstances. Our proposed approach does not involve any restraining assumptions concerning environmental variables or predator-prey relationships. Rather it is based on the simple premise that if observed on an year-to-year basis, the population size will be noted to either have gone up or come down as compared to last year. The conceptualization is borrowed from the theory of asset pricing in stochastic finance. Our results indicate that an extreme event with a maximum shock size (i.e. the maximum number of immediate mortalities that may be caused by an extreme event) exceeding two-thirds the size of the pristine population can potentially drive any animal species with a 2-year life cycle to extinction for any fecundity level.

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Sukanto Bhattacharya, Sreepurna Malakar. 2005-06-22. Monte Carlo modeling of the effect of extreme events on the extinction dynamics of animal species with 2-year life cycles. https://arxiv.org/abs/q-bio/0506035

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