Meta-analyses of published correlation coefficients between multilocus heterozygosity (MLH) and two fitness surrogates, growth rate and fluctuating asymmetry, suggested that the strength of these correlations are generally weak. A variety of plants and animals was included in the meta-analyses. A statistically homogeneous group of MLH-growth rate correlation coefficients that included both plants and animals yielded a common correlation of r = 0.133. A common correlation of r = -0.170 was estimated for correlations between MLH and fluctuating asymmetry in three species of salmonid fishes. These results suggest that selection, including overdominance, has at most a weak effect at allozyme loci and cast some doubt on the widely held notion that heterozygosity and individual fitness are strongly correlated.

Meta-analyses of published correlation coefficients between multilocus heterozygosity (MLH) and two fitness surrogates, growth rate and fluctuating asymmetry, suggested that the strength of these correlations are generally weak. A variety of plants and animals was included in the meta-analyses. A statistically homogeneous group of MLH-growth rate correlation coefficients that included both plants and animals yielded a common correlation of r = 0.133. A common correlation of r = -0.170 was estimated for correlations between MLH and fluctuating asymmetry in three species of salmonid fishes. These results suggest that selection, including overdominance, has at most a weak effect at allozyme loci and cast some doubt on the widely held notion that heterozygosity and individual fitness are strongly correlated.

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Techniques for obtaining DNA noninvasively or nonlethally are highly desirable in molecular genetic studies of protected species, and several advances have been made in these types of sampling and extraction techniques. Insects present a unique set of difficulties in this regard that are not present when working with most vertebrates. This study evaluated the effectiveness of several nonlethal sampling techniques for larval and adults of the federally listed endangered dragonfly Somatochlora hineana (Williamson) (Odonata: Corduliidae). Fecal pellets and shed exuviae from captive S. hineana larvae did not provide high enough quality DNA for microsatellite analyses. Invasive, but nonlethal, wing clips from adults and tarsi from larvae provided high-quality DNA that amplified 10 microsatellite markers for this species. Ten loci were polymorphic in 94 specimens with four to 14 alleles per locus. Two populations in WI had average observed heterozygosity of 0.47, which is within the range reported for other odonates. Our sampling techniques and these new microsatellite markers provide an essential tool for determining the genetic structure of S. hineana populations throughout its range.

The black-tailed prairie dog (Cynomys ludovicianus) is a keystone species on the mid- and short-grass prairies of North America. The species has suffered extensive colony extirpations and isolation as a result of human activity including the introduction of an exotic pathogen, Yersinia pestis, the causative agent of sylvatic plague. The prairie dog flea, Oropsylla hirsuta, is the most common flea on our study colonies in north-central Montana and it has been shown to carry Y. pestis. We used microsatellite markers to estimate the level of population genetic concordance between black-tailed prairie dogs and O. hirsuta in order to determine the extent to which prairie dogs are responsible for dispersing this potential plague vector among prairie dog colonies. We sampled fleas and prairie dogs from six prairie dog colonies in two regions separated by about 46 km. These colonies were extirpated by a plague epizootic that began months after our sampling was completed in 2005. Prairie dogs showed significant isolation-by-distance and a tendency toward genetic structure on the regional scale that the fleas did not. Fleas exhibited higher estimated rates of gene flow among prairie dog colonies than the prairie dogs sampled from the same colonies. While the findings suggested black-tailed prairie dogs may have contributed to flea dispersal, we attributed the lack of concordance between the population genetic structures of host and ectoparasite to additional flea dispersal that was mediated by mammals other than prairie dogs that were present in the prairie system.