Theoretical ecologists have long sought to understand how the persistence of populations depends on biotic and abiotic factors. Classical work showed that demographic stochasticity causes the mean time to extinction to increase exponentially with population size, whereas variation in environmental conditions can lead to a power-law scaling. Recent work has focused especially on the influence of the autocorrelation structure ('color') of environmental noise. In theoretical physics, there is a burst of research activity in analyzing large fluctuations in stochastic population dynamics. This research provides powerful tools for determining extinction times and characterizing the pathway to extinction. It yields, therefore, sharp insights into extinction processes and has great potential for further applications in theoretical biology.
Bibliographical noteFunding Information:
We thank Sami Ojanen for his help with preparing the figures. This study was supported by the Academy of Finland (Grant no. 124242 to OO), the European Research Council (ERC Starting Grant no. 205905 to OO), the Israel Science Foundation (Grant No. 408/08 to BM), and the US-Israel Binational Science Foundation (Grant No. 2008075 to BM).