Mating system affects population performance and extinction risk under environmental challenge

Mating system affects population performance and extinction risk under environmental challenge.

Failure of organisms to adapt to sudden environmental changes may lead to extinction. The type of mating system, by affecting fertility and the strength of sexual selection, may have a major impact on a population's chances to adapt and survive. Here, we use experimental evolution in bulb mites (Rhizoglyphus robini) to examine the effects of the mating system on population performance under env...

How colored environmental noise affects population extinction.

Environmental noise can cause an exponential reduction in the mean time to extinction (MTE) of an isolated population. We study this effect on an example of a stochastic birth-death process with rates modulated by a colored (that is, correlated) Gaussian noise. A path integral formulation yields a transparent way of evaluating the MTE and finding the optimal realization of the environmental noi...

Extinction risk under coloured environmental noise

Equilibrium and Extinction In a Trisexual Diploid Mating System

In order to study the dynamics of a three-sex (trisexual) mating system, we extend the heterogametic sex-determining mechanism, used in many species, to include three sexes: XX, XY and YY. In this model, non-like types may mate, but like-types may not mate. We compare the dynamics of this system to a Mendelian system under Hardy-Weinberg conditions, and coin the term Trisexual Equilibrium to de...

Confounding Environmental Colour and Distribution Shape Leads to Underestimation of Population Extinction Risk

The colour of environmental variability influences the size of population fluctuations when filtered through density dependent dynamics, driving extinction risk through dynamical resonance. Slow fluctuations (low frequencies) dominate in red environments, rapid fluctuations (high frequencies) in blue environments and white environments are purely random (no frequencies dominate). Two methods ar...