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High variability and disomic segregation of microsatellites in the octaploid Fragaria virginiana Mill (Rosaceae)

The objectives of the present study were to develop microsatellite markers for the wild strawberry, Fragaria virginiana, to evaluate segregation patterns of microsatellite alleles in this octoploid species, and assess genetic variability at microsatellite loci in a wild population. A genomic library was screened for microsatellite repeats and several PCR primers were designed and tested. We also tested the use of heterologous primers and found that F. virginiana primers amplified products in cultivated strawberry, Fragaria ¿ ananassa Duch. and Fragaria chiloensis.

Limited hybridization between Quercus lobata and Q. douglasii (Fagaceae) in a mixed stand in central coastal California

Role of ecological modeling in risk assessment

Toxic chemicals can exert effects on all levels of the biological hierarchy, from cells to organs to organisms to populations to entire ecosystems. However, most risk assessment models express their results in terms of effects on individual organisms, without corresponding information on how populations, groups of species, or whole ecosystems may respond to chemical stressors.

Realism and relevance of ecological models used in chemical risk assessment

Ecological models have been developed and used in management of renewable natural resources, conservation biology, and assessments of ecological risks posed by toxic chemicals and other stressors. Because few models have been developed specifically for use in assessing chemical risks, this study examines the realism and relevance of a wide range of ecological models from the perspective of assessing toxicological risks posed by chemicals.

Treatments of uncertainty and variability in ecological risk assessment of single-species populations

The selection of the most appropriate model for an ecological risk assessment depends on the application, the data and resources available, the knowledge base of the assessor, the relevant endpoints, and the extent to which the model deals with uncertainty. Since ecological systems are highly variable and our knowledge of model input parameters is uncertain, it is important that models include treatments of uncertainty and variability, and that results are reported in this light. In this paper we discuss treatments of variation and uncertainty in a variety of population models.

Analysis and portrayal of uncertainty in a food-web exposure model

Using population models for conservation management of an endangered Australian plant, Grevillea caleyi

A population viability analysis for a long lived perennial: Xanthorrhoea resinifera

The use of decision-making tools in systematic conservation planning

A methodological framework for the California Legacy Project