Premium
Fitness landscape of sympatric pupfishes a useful tool for visualizing speciation
Author(s) -
Keepers Kyle G.,
Martin Andrew P.
Publication year - 2014
Publication title -
molecular ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.619
H-Index - 225
eISSN - 1365-294X
pISSN - 0962-1083
DOI - 10.1111/mec.12727
Subject(s) - sympatric speciation , biology , ecological speciation , ecology , genetic algorithm , generalist and specialist species , fitness landscape , gene flow , parapatric speciation , adaptive radiation , evolutionary biology , sympatry , phylogenetic tree , habitat , genetic variation , population , gene , biochemistry , demography , sociology
Arguably the most useful model of evolution emerged from the mind of Sewall Wright when he invented the fitness landscape (Wright [Wright S, 1932]). In a recent issue of Molecular Ecology , Martin & Feinstein ([Martin CH, 2014]) investigate the genetics and demographic history of an adaptive radiation of pupfish on San Salvador Island. Since the founder species colonized the island 10 000 years ago, two descendent species have appeared and in several lakes all three species (a durophage, a scale‐eater, and the generalist ancestral form) coexist. The three species are thought to occupy three distinct fitness peaks. The durophage and generalists' peaks are close, whereas the scale‐eater's peak is predicted to be distant and separated from the other two by a deep valley. Consistent with this view, gene flow between the two species on close fitness peaks is greater than the gene flow between these two species and the third species on a more distant peak. Correspondingly, the inferred fitness landscape predicts progress towards speciation, with more limited separation of species on close peaks, and that speciation is more complete for the scale‐eater. The article provides an illustrative example of the power afforded by analysis of large numbers of SNP s for estimating key parameters underlying evolutionary divergence.