Molecular Ecology

AbstractMolecular ecology is a field of biology that uses molecular genetic data to address ecological questions in disciplines as varied as genomics, biogeography, conservation genetics, and behavioural ecology. The majority of studies in molecular ecology use data that are based on deoxyribonucleic acid (DNA) sequences, an approach that has been greatly enhanced in recent years by the advent of next‐generation sequencing, which collectively refers to methods that allow researchers to simultaneously sequence up to several thousand genes from a very small amount of starting DNA. In addition to DNA sequences, researchers can compare individuals and populations by characterising different versions of a particular gene (known as alleles) based on their sizes. By using molecular markers such as DNA sequences or allele sizes, researchers can quantify the genetic diversity within populations and the genetic similarity among populations. This in turn allows them to address specific questions pertaining to the ecology and evolution of species.Key Concepts:Molecular ecology uses molecular genetic data to address ecological questions.A variety of molecular markers can be used to genetically characterise species and populations.Next‐generation sequencing has greatly enhanced our ability to collect large amounts of genetic data at relatively low cost.Molecular genetic data from natural populations allow researchers to quantify the genetic diversity within populations, and the genetic similarity among populations.Genetic diversity is required for the long‐term survival of populations and species, and is influenced by a range of different factors.Gene flow among populations strongly influences their genetic similarity.Landscape genetics helps researchers to understand barriers to gene flow across a series of landscapes.Eco‐genomics is a field of study that seeks to understand the genetic mechanisms behind adaptation and natural selection.Behavioural molecular ecology uses highly variable molecular markers to differentiate individuals and to assign parentage.Phylogeography uses molecular genetic data to infer some of the ways in which historical events and processes have shaped the current distributions of species.