IdentityByDescentDispersal.jl: Inferring dispersal rates with identity-by-descent blocks

Abstract: The population density and per-generation dispersal rate of a population are central parameters in the study of evolution and ecology. The distribution of recent coalescent events between individuals in space can be used to estimate such quantities through the distribution of identity-by-descent (IBD) blocks. An IBD block is defined as a segment of DNA that has been inherited by a pair of individuals from a common ancestor without being broken by recombination. We introduce $\texttt{IdentityByDescentDispersal.jl}$, a Julia package for estimating effective population densities and dispersal rates from observed spatial patterns of IBD shared blocks. It implements the inference scheme proposed by Ringbauer, Coop, and Barton (2017). The package provides a user-friendly interface, supports efficient gradient-based optimization and accommodates arbitrary user-defined demographic models through numerical integration. This software aims to encourage a wider audience to utilize spatial genetic data for estimating dispersal rates, thereby motivating further research and expanding its applications.