Genetic Coupling of Female Mate Choice with Polygenic Ecological Divergence Facilitates Stickleback Speciation

The Role of the Sex Chromosomes in the Inheritance of Species Specific Traits of the Shape of the Copulatory Organ in Drosophila

“…An allele that expands the ecological niche for the species will be fixed rapidly in a new QTL. Experiments on QTL mapping support the conclusions based on model analyses (Terekhanova et al, 2014;Lin et al, 2016;Lendenmann et al, 2016;Bay et al, 2017). It is safe to say that, along with additive effects, dominant interactions of alleles gain principal importance.…”

Genetic coupling of signal and preference facilitates sexual isolation during rapid speciation

“…Signal and preference traits are often modeled with independent hereditary bases where assortative mating alone results in linkage disequilibrium among unlinked loci. Yet recent findings consistent with a coupled basis to natural variation in signals and preferences in multiple taxa 26–30 suggest a key to understanding signal-preference coevolution. Laupala crickets exemplify these patterns, exhibiting distinctive male songs and female acoustic preferences that have diverged between closely related species in an extremely rapid speciation context 34 .…”

“…In contrast, genetic coupling are often considered unlikely 19 . However, recent evidence from quantitative trait locus (QTL) mapping and introgression studies supports the presence of colocalized genes underlying interspecific signal-preference variation in crickets, butterflies, fruit flies, and fish 26–30 . In addition, lab-induced mutations that alter both male signals and female preferences in fish and flies 31–33 demonstrate that pleiotropic genes underlying signals and preferences do exist in the genomes of sexual organisms.…”

Notes from a snail island: Littorinid evolution and adaptation

“…However, the effect of ecotype on mate choice differed among islands—suggesting some snails are choosier than others, whereas some are happy to mate regardless of the ecotype of the partner presented to them. A recent experimental cross in limnetic–benthic sticklebacks has shown that QTL underlying mate choice and body morphology overlap with a QTL that determines ecological niche, providing support for coupling (either by linkage or pleiotropy) of assortative mating and ecological divergence (Bay et al., ). Littorinids are amenable to experimental rearing and could easily be investigated with a similar approach, perhaps also incorporating adaptive traits such as thermal tolerance (see below).…”