Understanding evolutionary rescue and parallelism in response to environmental stress

Evolutionary rescue, the process by which populations facing environmental stress avoid extinction through genetic adaptation, is a critical area of study in evolutionary biology. The order in which mutations arise and get established will be relevant to the population's rescue. This study investigates the degree of parallel evolution at the genotypic level between independent populations facing environmental stress and subject to different demographic regimes. Under density regulation, two regimes exist: in the former, the population can restore positive growth rates by adjusting its population size or through adaptive mutations, whereas in the second regime, the population is doomed to extinction unless a rescue mutation occurs. Analytical approximations for the likelihood of evolutionary rescue are obtained and contrasted with simulation results. We show that the initial level of maladaptation and the demographic regime significantly affect the level of parallelism. There is an evide..., , , ###### DATA\_AVAILABILITY

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This repository contains 3 files:

(1) One \".cpp\" file for the estimate of the rescue/extinction probability:

C++ source code \"rescue-L.cpp\"

Requires the GSL scientific library:

Ubuntu systems installation through terminal:

(C++) ~ sudo apt-get install build-essential
(GSL) ~ sudo apt-get install gsl-bin
(GSL) ~ sudo apt-get install libgsl-dev

Ubuntu systems compilation through terminal:

~ c++ -O3 rescue-L.cpp -o [executable_name] -lm -lgsl -lgslcblas

After compilation, we will get an executable.

To run the code, we must provide it with input data.

The input data are:

i- sequence size
ii- carrying capacity
iii - mutation probability
iv - number of independent landscapes
v - maximum time (usually before this maximum as a consequence of extinction, or because t...