The quantitative genetics of incipient speciation: heritability and genetic correlations of skeletal traits in populations of diverging Favia fragum ecomorphs.

Recent speciation events provide potential opportunities to understand the microevolution of reproductive isolation. We used a marker-based approach and a common garden to estimate the additive genetic variation in skeletal traits in a system of two ecomorphs within the coral species Favia fragum: a Tall ecomorph that is a seagrass specialist, and a Short ecomorph that is most abundant on coral reefs. Considering both ecomorphs, we found significant narrow-sense heritability (h(2) ) in a suite of measurements that define corallite architecture, and could partition additive and nonadditive variation for some traits.

Estimation of mating systems in Short and Tall ecomorphs of the coral Favia fragum.

We used 15 microsatellite markers to estimate the selfing rate (s), outcrossing rate (t(O) ) and hybridization between partially sympatric ecomorphs (t(H) ) of the coral Favia fragum. Genotyping of progeny arrays revealed complete self-fertilization in the Tall ecomorph and low outcrossing (t(O)  + t(H)  < 1%) in the Short ecomorph. Further, all larvae could be assigned with high probability to the same population as their parental dam, indicating no hybridization between ecomorphs (t(H)  = 0).

Fifteen new microsatellite markers for the reef coral Favia fragum and a new Symbiodinium microsatellite.

Sixteen new microsatellite loci were isolated from the Tropical Atlantic coral Favia fragum. One locus amplified with pure zooxanthellae DNA template, revealing a symbiont (Symbiodinium) origin. We genotyped 48 short and 45 tall ecomorphs of F.

High genetic diversity and no inbreeding in the endangered copper redhorse, Moxostoma hubbsi (Catostomidae, Pisces): the positive sides of a long generation time.

The evolutionary potential of a species is determined by its genetic diversity. Thus, management plans should integrate genetic concerns into active conservation efforts. The copper redhorse (Moxostoma hubbsi) is an endangered species, with an endemic distribution limited to the Richelieu River and a short section of the St Lawrence River in Quebec, Canada.

Consequences of unequal population size, asymmetric gene flow and sex-biased dispersal on population structure in brook charr (Salvelinus fontinalis).

Unravelling relationships between dispersal and population structure requires considering the impacts of assumption violations of indirect gene flow models in a given system. We combined temporal, individual and coalescent-based analyses of microsatellite DNA variation to explore the general hypothesis that unequal effective population size (Ne), asymmetric gene flow (m) and nonrandom (sex-biased) individual dispersal had an important effect on spatiotemporal population structuring in lake-dwelling brook charr (Salvelinus fontinalis). This integrative examination shed light on the dichotomous structuring observed between an outlet and three tributary-spawning populations and their potential for adaptive divergence.