DOI: 10.5061/dryad.mw6m90641
title: Evolution of interspecific variation in marine larval dispersal kernels: The role of larval navigation ability

description: Dispersal is an integral part of the life cycle of most organisms, with
 consequences for individual fitness, population genetic structure, species
 ranges, community assembly, and conservation. Dispersal patterns, and the
 traits underlying them, have the potential to evolve in response to
 selection and other evolutionary forces. Here, we investigate two opposing
 components of selection by quantifying their corresponding costs in a
 spatially-autocorrelated, patchy environment. Kin competition is expected
 to select for longer dispersal distances, while the risk of being unable
 to locate suitable habitat should favor shorter dispersal distances. We
 illustrate the tradeoff between these two components of selection by
 considering their costs across dispersal distances, among dispersal
 kernels, and through evolutionary time. We then apply this framework to an
 unsolved empirical problem: explaining the interspecific variation in
 spatial scale of marine larval dispersal. We propose variation in the
 ability of larvae to navigate to suitable habitat as a potential source of
 variation in dispersal distance, and find that species with greater
 navigation ability evolve dispersal kernels that allocate more offspring
 to longer distances. Navigation also decreases the impact of both costs,
 suggesting the potential for coevolution of navigation ability and the
 dispersal kernel.
description: # Evolution of interspecific variation in marine larval dispersal kernels:
 The role of larval navigation ability [Access the dataset on
 Dryad](https://datadryad.org/dataset/doi:10.5061/dryad.mw6m90641) This
 dataset is from the paper titled "Evolution of interspecific
 variation in marine larval dispersal kernels: the role of larval
 navigation ability", by: E. Lou Schlatter, Allison K. Shaw, Colleen
 T. Webb, Peter Buston, published in: Oikos, and is based on the model from
 the paper titled "The evolution of marine larval dispersal kernels in
 spatially structured habitats: analytical models, individual-based
 simulations, and comparisons with empirical estimates" by: Allison K
 Shaw, Cassidy C D'Aloia, Peter M Buston, published in: The American
 Naturalist. ## Contents KernelEvolution_Oikos.zip is a compressed file
 containing the following **`folders`**, **`files`**, and `variables`: 1.
 Folder **`files_runsims`**: contains Matlab code (.m and .mlx files) for
 running model simulation data used for Figures 1-2 in the paper. Contains
 files: * **`1_Preparation.mlx`**: runs function to create simulation
 environment: 2 x 512 habitable grid, surrounded by uninhabitable space. *
 **`2_Trajectories.mlx`**: runs functions to simulate evolutionary
 trajectories from 4 different initial displacement strategies, and for 3
 levels of larval navigation (nmax=0, 1, and 2). * **`3_NK_surfaces.mlx`**:
 generates a set of displacement strategies representing the entire range
 of possible distribution shapes. Then, for each element of the set, runs
 function to calculate nonviable habitat and kin competition costs in a
 population where all individuals share that strategy. *
 **`fn_create_env_bounded.m`**: function to create environment. *
 **`fn_create_initial_pop.m`**: function to generate population data that
 can be used to initialize a simulation. * **`fn_IBM_dispersal.m`**:
 function to run a simulation of the individual-based model. *
 **`fn_many_costben_sims.m`**: runs the function to calculate nonviable
 habitat cost and kin competition many times, once for each of a set of
 displacement strategies. * **`fn_one_costben_sim.m`**: function to
 calculate nonviable habitat and kin competition costs for a population in
 which all individuals share the same displacement strategy, by simulating
 dispersal of a single generation of offspring. * **`NK_kernel_set.mat`**:
 data file containing the set of displacement strategies generated in
 3_NK_surfaces.mlx. Contains variable: * `kernels`: matrix of kernels (each
 row a kernel, each column a distance probability) representing the entire
 range of possible distribution shapes, used in 3_NK_surfaces.mlx. 2.
 Folder **`output_environments`**: contains Matlab data file (.mat file)
 for the simulation environment, with variables: * `b` = number of
 offspring per site in the environment * `bvec` = vector of offspring
 capacity of each viable site, 1...S * `dists` = array of distances between
 each site. Width of one site = one unit of distance. * `E` = 2D matrix of
 patches, marked as viable (1) and nonviable (0) * `patches` = vector of
 birth rates at each site * `S` = number of actual viable sites in the
 environment * `sx` = number of sites in the x-dimension of the environment
 * `sy` = number of sites in the y-dimension of the environment * `via_ID`
 = list of viable patches in E, marked by their index number * `xcoord` =
 list of x-coordinates for all patches in E * `ycoord` = list of
 y-coordinates for all patches in E 3. Folder **`output_simulations`**:
 contains Matlab data files (.mat files) for each individual-based
 simulation. Contents: * Folder **`NK_surfaces`** (data on kin competition
 and nonviable habitat costs for all displacement strategies in
 NK_kernel_set.mat. One file for each value of nmax = 0, 1, and 2.)
 Variables: * `kernels` = matrix of kernels used in simulation (each row a
 kernel, each column a distance probability) * `out_fitness`,
 `out_kincost`, `out_mortcost` = population-wide averages of fitness, kin
 competition cost, and nonviable habitat cost for each kernel *
 `dist_fitness`, `dist_kincost`, `dist_mortcost` = distance-specific values
 of fitness, kin competition cost, and nonviable habitat cost for each
 kernel - Folder **`trajectories`** (data on evolutionary trajectories for
 4 initial displacement strategies x 3 values of nmax = 12 total
 simulations). Variables: * Output variables used in plotting: *
 `dtime_avg` = population mean of dispersal parameters at each timestep *
 `kincomp_cost` = kin competition cost at each distance and timestep *
 `mortality_cost` = nonviable habitat cost at each distance and timestep -
 Saved simulation parameters: * `gflag` = whether (1) or not (0) to show
 plots during simulation * `eflag` = which environment to use: 1=unbounded,
 2=bounded, 3=reef, 4=heterogeneous * `sx` = number of sites in the
 x-dimension of the environment * `sy` = number of sites in the y-dimension
 of the environment * `nbins_env` = max number of dispersal bins the env
 can support (must be &gt;= 2) * `nbins` = how many dispersal bins to
 actually use * `nmax` = maximum larval navigation distance (behavior) *
 `G` = number of total generations to simulate * `b` = offspring produced
 per individual * `p` = probability of surviving dispersal * `del` =
 fraction of dispersal probability to move during mutation * `pop_init` =
 initial population array (e.g., from previous simulation) *
 `saveto_filepath` = where to save output files 4. Folder
 **`files_plotsims`**: contains Matlab code (file 4_Plots.mlx) for plotting
 Figures 1-2 in the paper, using the above .mat files.