Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
172
result(s) for
"Cooper, Becky"
Sort by:
Genetic Effects of Captive Breeding Cause a Rapid, Cumulative Fitness Decline in the Wild
Captive breeding is used to supplement populations of many species that are declining in the wild. The suitability of and long-term species survival from such programs remain largely untested, however. We measured lifetime reproductive success of the first two generations of steelhead trout that were reared in captivity and bred in the wild after they were released. By reconstructing a three-generation pedigree with microsatellite markers, we show that genetic effects of domestication reduce subsequent reproductive capabilities by ∼40% per captive-reared generation when fish are moved to natural environments. These results suggest that even a few generations of domestication may have negative effects on natural reproduction in the wild and that the repeated use of captive-reared parents to supplement wild populations should be carefully reconsidered.
Journal Article
Reproductive Success of Captive-Bred Steelhead Trout in the Wild: Evaluation of Three Hatchery Programs in the Hood River
Population supplementation programs that release captive-bred offspring into the wild to boost the size of endangered populations are now in place for many species. The use of hatcheries for supplementing salmonid populations has become particularly popular. Nevertheless, whether such programs actually increase the size of wild populations remains unclear, and predictions that supplementation fish drag down the fitness of wild fish remain untested. To address these issues, we performed DNA-based parentage analyses on almost complete samples of anadromous steelhead (Oncorhynchus mykiss) in the Hood River in Oregon (U.S.A.). Steelhead from a supplementation hatchery (reared in a supplementation hatchery and then allowed to spawn naturally in the wild) had reproductive success indistinguishable from that of wild fish. In contrast, fish from a traditional hatchery (nonlocal origin, multiple generations in hatcheries) breeding in the same river showed significantly lower fitness than wild fish. In addition, crosses between wild fish and supplementation fish were as reproductively successful as those between wild parents. Thus, there was no sign that supplementation fish drag down the fitness of wild fish by breeding with them for a single generation. On the other hand, crosses between hatchery fish of either type (traditional or supplementation) were less fit than expected, suggesting a possible interaction effect. These are the first data to show that a supplementation program with native brood stock can provide a single-generation boost to the size of a natural steelhead population without obvious short-term fitness costs. The long-term effects of population supplementation remain untested.
Journal Article
Mapping Manhattan
Armed with blank maps that she printed by hand, Becky Cooper hit New York City, she handed strangers she met the gray outline of their island and asked them to \"map their Manhattan\". Mapping Manhattan includes 75 maps from both anonymous mapmakers and from notable New Yorkers, and will also contain a blank map that can be filled out by the reader.
eBook
Fewer Dead White Guys: Creating a Multicultural AP English Curriculum
Choosing Materials for this Course When undertaking the review of the previous curriculum, staff polled former students regarding their AP experience, reviewed articles and blogs that discussed diversity in reading content, observed how other local groups and libraries made their reading selections, and explored local foundations and organizations that promote opportunities for social justice engagement for young people. What would help them engage in the process of determining how they contribute toward building community? Because the AP exams reflect the \"Canon,\" which is slowly evolving, certain traditional authors and texts, such as More's Utopia, would be kept in the curriculum to keep students competitive. Attending workshops or doing individual research on diversity, inclusion, and representation in the classroom; shadowing experienced teachers; and participating in classes and workshops that enable instructors to explore how to teach more inclusive texts and work through their own implicit bias may help with these issues. Instructors need to beware of dividing their classroom. Because we appear to have such a widely polarized and increasingly hostile political climate, making time to create a safe space to discuss the work, including the fact that some students will experience discomfort, is key.
Journal Article
Parasite genotypes identify source populations of migratory fish more accurately than fish genotypes
DNA-based assignment of individuals to their population of origin has many applications such as mixed-stock analysis, identifying individuals from protected populations, and elucidating migration patterns. However, low genetic differentiation among populations will cause misassignments. Thus, an alternative means of determining an individual's population of origin is needed in cases where there is little or no neutral differentiation among source populations. Here, we test the hypothesis that parasite genotypes can be used to identify the origins of hosts more accurately than host genotypes. Using microsatellite markers from steelhead trout and their trematode parasites, we show that the odds of correct assignment are four times greater with the parasite's genotypes than with the host's genotypes. Our analyses show that this result is simply explained by the greater genetic structure among populations of the trematode parasite. Recent studies on the comparative genetic structure of other host and parasite species suggest that our results are not unusual or unique to the host-parasite system we studied. Thus, our work indicates that parasites will be useful for a wide range of applied and basic research that requires the assignment of individuals to source populations.
Journal Article
