Development and localization of microsatellite markers for the sibling species Chironomus riparius and Chironomus piger (Diptera: Chironomidae)
Five variable microsatellite loci are reported for the nonbiting midge species Chironomus riparius and Chironomus piger. All loci show considerable intraspecific variation and species-specific alleles, which allow to discriminate among the two closely related species and their interspecific hybrids, and to estimate genetic diversity within and between populations. Additionally, the loci were localized on C. riparius polytene chromosomes to verify their single copy status and investigate possible chromosomal linkage. The described markers are used in different studies with regard to population and ecological genetics and evolutionary ecotoxicology of Chironomus.
Fitness differences and persistent founder effects determine the clonal composition during population build-up in Daphnia
During the initial stages of population build-up in new habitats, the time at which immigrants arrive may infl uence their contribution to the population and thus determine population genetic structure. While the numerical advantage associated with founder eff ects may promote dominance of the off spring of early colonizers, fi tness diff erences associated with ecological diff erences among genotypes may potentially overwhelm these founder eff ects. We conducted an outdoor mesocosm experiment to test whether the sequence of arrival determines the relative contribution of genetic lineages (clones) to populations of the water fl ea Daphnia . A set of D. galeata clones was inoculated pairwise…
Spontaneous rate of clonal mutations inDaphnia galeata
AbstractMutations are the ultimate source of heritable variation and therefore the fuel for evolution, but direct estimates exist only for few species. We estimated the spontaneous nucleotide mutation rate among clonal generations in the waterfleaDaphnia galeatawith a short term mutation accumulation approach. Individuals from eighteen mutation accumulation lines over five generations were deep genome sequenced to count de novo mutations that were not present in a pool of F1 individuals, representing the parental genotype. We identified 12 new nucleotide mutations in 90 clonal generational passages. This resulted in an estimated haploid mutation rate of 0.745 x 10-9(95% c.f. 0.39 x 10-9− 1.…