Alternative reproductive tactics and evolutionary rescue
Cite this dataset
Knell, Robert; Parrett, Jonathan M. (2024). Alternative reproductive tactics and evolutionary rescue [Dataset]. Dryad. https://doi.org/10.5061/dryad.9zw3r22p1
Abstract
Almost all life on earth is facing environmental change, and understanding how populations will respond to these changes is of urgent importance. One factor that is known to affect the speed by which a population can evolve when faced with changes in the environment is strong sexual selection. This increases the adaptive capacity of a population by increasing reproductive skew towards well-adapted (usually) males who will, on average, be best able to compete for matings. This effect could potentially be disrupted when males pursue alternative reproductive tactics (ARTs), whereby males within a species exhibit qualitatively different behaviours in their pursuit of matings. ARTs are diverse but one common class is those expressed through condition-dependent polyphenism such that high-quality, well-adapted males compete aggressively for mates and low-quality, poorly adapted males attempt to acquire matings via other, non-aggressive behaviours. Here, using an individual-based modelling approach, we consider the possible impacts of ARTs on adaptation and evolutionary rescue. When the ART is simultaneous, meaning that low-quality males do engage in contests but also pursue other tactics, adaptive capacity is reduced and evolutionary rescue, where a population avoids extinction by adapting to a changing environment, becomes less likely. This is because the use of the ART allows low-quality males to contribute more maladaptive genes to the population than would happen otherwise. When the ART is fixed, however, such that low-quality males will only use the alternative tactic and do not engage in contests, we find the opposite: adaptation happens more quickly and evolutionary rescue when the environment changes is more likely. This surprising effect is caused by an increase in the mating success of the highest quality males who face many fewer competitors in this scenario—counterintuitively, the presence of males pursuing the ART increases reproductive skew towards those males in the best condition.
README: Alternative reproductive tactics and evolutionary rescue
Dataset is a set of outputs from simulation modelling of the influence of the use of alternative reproductive tactics by males on adaptation rates and the likelihood of evolutionary rescue in a changing environment. The code for the model and for running simulations and visualising the results is also included.
Description of the data and file structure
There are four data files with model output. These are:
output_drectional_100reps.csv
Simulation output used for the analysis of extinction probability (figure 2)
output_step_return_100reps.csv
Simulation output used for the analysis of return times after step change (figure 3)
output_effect_size_100reps.csv
Simulation output used for the analysis of Critical Rates of Environmental Change (Supplementary material)
output_ART_success_100reps.csv
Simulation output used for the analysis of the effect of increasing the success of males following the ART (supplementary material)
All of them but output_step_return.csv have the following variables:
K_cap the carrying capacity of the environment
group_size the size of the group foals from which females make a choice
max_offspring the maximum number of offspring a female can have in a single breeding season
alpha the cost of expressing a display trait
ART_success a variable which adjusts the probability of a male pursuing the ART gaining a mating
threshold the condition threshold below which a male will pursue the ART
type the kind of ART: simultaneous or fixed
beta a variable controlling the strength of female preference
rep the replicate number
extinct whether the population became extinct (1 = extinct, 0=persists)
time_to_extinct if the population became extinct, the timestep when this happened
output_step_return.csv has K_cap, group_size, max_offspring, threshold, type, beta, rep and also
return_time the time taken for the population to adapt to a new environment following a step change in the environment.
Sharing/Access information
These data etc. are also archived on GitHub
Code/Software
Two R scripts are included:
Alternative_tactics_model.R this is the code for the model itself.
ART_sims_and_analysis.R this script has code for running the simulations and for visualising the data.
Both scripts were developed and run in R 4.3.0
The model code requires the moments package.
The code for running simulations and data visualisation requires the following packages:
doParallel
foreach
dplyr
ggplot2
moments
readr
MASS
Methods
Data are outputs from simulation modelling.
Funding
Biotechnology and Biological Sciences Research Council, Award: EVL3-23-0092.R2
National Science Center, Award: 2020/39/D/NZ8/00069