Genetic basis of floral mechanical isolation between two hummingbird-pollinated plants

Because floral evolution contributes to reproductive isolation, it provides an opportunity to study the genetic basis of speciation, in terms of the number, effect size, and mode of action of the loci involved. Using QTL mapping, we examined the genetic architecture of floral morphological traits involved in an evolutionary switch from bill to forehead pollen placement between two taxa of hummingbird-pollinated Neotropical understory herbs that are reproductively isolated by these floral differences.