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Conserving genetic diversity requires an assessment of the distribution of genetic variants in relation to patterns of land
use and environmental variation at a regional scale. This assessment requires a novel approach to integrating and analyzing
the genetic and environmental data across spatial scales. To explore the integration of genetic data with other geospatial
data sets, we developed a GIS-based approach for examining patterns of genetic diversity for several species of salamanders
in southern Appalachians. The genetic data, from allozyme surveys in the genetics literature, were integrated into a GIS database
along with related attributes including population identifications and spatial locations. Using existing geospatial data,
we classified sample locations as being either protected from anthropogenic disturbance (e.g., National Parks, Wilderness
Areas) or as unprotected (e.g., private lands, multiple-use lands in National Forests). We used multidimensional scaling of
allelic frequencies and contributions of populations to interpopulation differences in allelic richness to determine which
populations had genetic characteristics most different from other populations in the sample. Measures of genetic differentiation
were integrated into the GIS database to facilitate spatial analysis and visualization of the indices in relation to land
use. This approach was useful for both identification of populations with components of genetic variation that were not well
represented at protected sites and for identifying areas of species distributions where more genetic sampling would be necessary
to make informed management decisions. Our approach could be readily adapted for use by managers and geneticists working with
other species and types of genetic markers. 相似文献
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Previously we reported that there are subfamily differences in drone production in queenless honey bee colonies, but these biases are not always explained by subfamily differences in oviposition behavior. Here we determine whether these puzzling results are best explained by either inadequate sampling of the laying worker population or reproductive conflict among workers resulting in differential treatment of eggs and larvae. Using colonies composed of workers from electrophoretically distinct subfamilies, we collected samples of adult bees engaged in the following behavior: true egg laying, false egg laying, indeterminate egg laying, egg cannibalism, or nursing (contact with larvae). We also collected samples of drone brood at four different ages: 0 to 2.5-h-old eggs, 0 to 24-h-old eggs, 3 to 8-day-old larvae, and 9 to 14-day-old larvae and pupae. Allozyme analyses revealed significant subfamily differences in the likelihood of exhibiting egg laying, egg cannibalism, and nursing behavior, as well as significant subfamily differences in drone production. There were no subfamily differences among the different types of laying workers collected from each colony, suggesting that discrepancies between subfamily biases in egg-laying behavior and drone production are not due to inadequate sampling of the laying worker population. Subfamily biases in drone brood production within a colony changed significantly with brood age. Laying workers had significantly more developed ovaries than either egg cannibals or nurses, establishing a physiological correlate for the observed behavioral genetic differences. These results suggest there is reproductive conflict among subfamilies and individuals within queenless colonies of honey bees. The implications of these results for the evolution of reproductive conflict, in both queenright and queenless contexts, are discussed. 相似文献
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We examined patterns of concurrent multiple mating in a live-bearing poeciliid fish, the sailfin molly (Poecilia latipinna). We tested whether the probability of multiple paternity was related to female body size or fertility and whether the rate
of multiple paternity varied among four populations that differed in their distributions of female body size and fertility.
We analyzed data on mother and offspring genotypes for three polymorphic allozymes by three techniques, including a maximum-likelihood
estimator that accounts for sampling error in both parental and offspring allele frequencies. The estimated rate of multiple
paternity varied between 0.09 and 0.85, and the rate in one population varied seasonally between 0.33 (spring) and 0.85 (autumn).
The variation in these rates was not associated with variation in body-size distributions among populations but was closely
associated with variation in size-specific fertility: populations with greater variation in female fertility had higher multiple-paternity
rates. Within two populations, logistic regression revealed that individual females of larger body size and greater size-specific
fertility were more likely to carry multiply sired broods. This result is consistent with observations made in one of the
populations 5 years earlier. In general, the results strongly suggest that the mating system varies markedly among conspecific
populations of sailfin mollies and that larger, more fertile females are the objects of intermale competition.
Received: 6 May 1996 / Accepted in revised form: 5 December 1996 相似文献
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