Molecular Ecology

Abstract

Molecular 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.

Diversification of Cerastium sylvaticum and C. subtriflorum on the margin of the south-eastern Alps

“…Whether this difference between C. sylvaticum and C. subtriflorum results from the presently continuous vs. fragmented distribution ranges or rather from survival in one vs. several glacial refugia remains unclear. As populations of C. subtriflorum are small and fragmented, stochasticity of genetic drift (faster fixation or elimination of mutations) is likely more pronounced (Freeland et al 2011;Masel 2011). On the other hand, multiple Pleistocene refugia have been suggested for several species in the western Balkan Peninsula (e.g.…”

Speciation slowing down in widespread and long-living tree taxa: insights from the tropical timber tree genus Milicia (Moraceae)

“…However, time of coalescence is readily affected by fluctuating population sizes, natural selection and immigration (Freeland et al, 2011). Zerega et al (2005) tracked back the biogeographical history and migration routes of most of genera known for Moraceae.…”

“…Although different approaches may lead to incongruent results because of reticulated evolution and incomplete lineage sorting, their integration in a pluralistic species concept can help make a consistent decision for taxonomic classification and conservation issues (Freeland et al, 2011). Hence, species delimitation requires to integrate data from molecular phylogeny, classical taxonomy (morphology-based), ecology, historical and contemporaneous biogeography in a way that permits the reconstruction of the evolutionary history of the target taxon (see, for example, Datwyler and Weiblen, 2004;Odee et al, 2012;Scotti-Saintagne et al, 2012).…”

Microevolution on Anthropogenically Changed Areas on the Example of Biscutella laevigata Plants from Calamine Waste Heap in Poland

“…We understand the microevolution as the processes of genetic differentiation within the population of a given species caused by mutations, genetic drift and natural selection determined by local environmental factors. New genetic adaptations are hereditary and increase the probability of survival, as well as the reproduction of plants in a particular environment [1][2][3][4].…”