Conservation Genetics of the Endangered San Diego Fairy Shrimp (Branchinecta Sandiegonensis) PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Conservation Genetics of the Endangered San Diego Fairy Shrimp (Branchinecta Sandiegonensis) PDF full book. Access full book title Conservation Genetics of the Endangered San Diego Fairy Shrimp (Branchinecta Sandiegonensis) by . Download full books in PDF and EPUB format.
Author:
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 81
Get Book Here
Book Description
Population genetic data are becoming an increasingly important tool in the conservation and management of endangered species. Statistical analysis of genetic data can inform agencies on population boundaries within a species, and help to infer processes that lead to genetic patterns, thereby influencing conservation decisions. This thesis examines population genetics in the endangered San Diego fairy shrimp, Branchinecta sandiegonensis, using multiple molecular markers. In order to quantify diversity and population structure, genetic data were collected from 50 pools from 23 pool complexes scattered throughout San Diego County at seven novel microsatellite loci. We tested the hypothesis that pool complex boundaries and geographic distance are important components of genetic structure. Microsatellite and mtDNA genetic patterns were compared to test for concordance between marker types. We also conducted preliminary tests for the effect of pool disturbance and hybridization on genetic diversity. Overall, results show that there is considerable microsatellite diversity within pools. In the preliminary tests, no significant change in genetic diversity in response to hybridization was detected. Disturbance may affect genetic diversity within pools, but it is unclear which component of disturbance is correlated with diversity. Overall, genetic differentiation among pool complexes is relatively strong. The hierarchical spatial arrangement of pools plays a significant role in genetic divergence among populations. Increasing geographic distances between sites is a significant gene flow barrier for this species, as has been found for other fairy shrimp species. Evidence of historical isolation between two divergent groups was also found. There is concordance among marker types, with some discrepancies. Population genetic structure in B. sandiegonensis across the study range is governed by gene flow restricted primarily to pool complexes. We recommend that pool complexes be treated as management units provided that pools are ecologically similar within them. Historical divergence among groups of pools should be taken into account as well, in order to maintain genetic variation and dispersal mechanisms across the species' range.
Author:
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 81
Get Book Here
Book Description
Population genetic data are becoming an increasingly important tool in the conservation and management of endangered species. Statistical analysis of genetic data can inform agencies on population boundaries within a species, and help to infer processes that lead to genetic patterns, thereby influencing conservation decisions. This thesis examines population genetics in the endangered San Diego fairy shrimp, Branchinecta sandiegonensis, using multiple molecular markers. In order to quantify diversity and population structure, genetic data were collected from 50 pools from 23 pool complexes scattered throughout San Diego County at seven novel microsatellite loci. We tested the hypothesis that pool complex boundaries and geographic distance are important components of genetic structure. Microsatellite and mtDNA genetic patterns were compared to test for concordance between marker types. We also conducted preliminary tests for the effect of pool disturbance and hybridization on genetic diversity. Overall, results show that there is considerable microsatellite diversity within pools. In the preliminary tests, no significant change in genetic diversity in response to hybridization was detected. Disturbance may affect genetic diversity within pools, but it is unclear which component of disturbance is correlated with diversity. Overall, genetic differentiation among pool complexes is relatively strong. The hierarchical spatial arrangement of pools plays a significant role in genetic divergence among populations. Increasing geographic distances between sites is a significant gene flow barrier for this species, as has been found for other fairy shrimp species. Evidence of historical isolation between two divergent groups was also found. There is concordance among marker types, with some discrepancies. Population genetic structure in B. sandiegonensis across the study range is governed by gene flow restricted primarily to pool complexes. We recommend that pool complexes be treated as management units provided that pools are ecologically similar within them. Historical divergence among groups of pools should be taken into account as well, in order to maintain genetic variation and dispersal mechanisms across the species' range.
Author: Bohonak, Andrew J.
Publisher:
ISBN:
Category : Biodiversity conservation
Languages : en
Pages : 10
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category : Electronic books
Languages : en
Pages : 60
Get Book Here
Book Description
The San Diego fairy shrimp (Branchinecta sandiegonensis ) is listed as federally endangered as a result of large-scale urbanization and subsequent vernal pool habitat loss. When new pools are created for mitigation or disturbed pools are restored, sediment from existing pools may be used for inoculation. The success of these projects can depend on whether source material is taken from a gene pool that is differentially adapted from the destination. Previous studies have suggested that there are at least two regional gene pools of San Diego fairy shrimp within San Diego County. A putative contact zone between these gene pools occurs primarily on land owned by the Marine Corps Air Station at Miramar (MCAS Miramar). We collected adult fairy shrimp from 51 pools across MCAS Miramar and extracted DNA from 1752 individuals. Using the mitochondrial gene cytochrome oxidase I (COI) in conjunction with seven microsatellite loci, we delineated the gene pool boundary with greater precision than was previously known. We also tested for additional population structure within each of these regional gene pools, based on a variety of poolspecific and landscape features. Both COI and microsatellite results were largely concordant at our study site and showed two gene pools with a distinct geographic break. Undisturbed pools were fixed for one gene pool, but disturbed pools showed greater admixture between the two genetic groups. The distinct geographic break between the two gene pools coincided with a large canyon on our study site. Isolation by distance analyses supported the canyon as a barrier to gene flow after we controlled for geographic distance. In addition, landscape genetic analyses showed presence of roads as a barrier to gene flow between pools. We designated six management units on MCAS Miramar, which will allow us to maintain species integrity, maintain the two regional gene pools, and maintain the integrity of complexes that show unusually high divergence. To best ensure the continued success of this endangered species, we recommend that inoculation of new pools use soil from within the same management group. Electronic appendices accompanying this thesis can be found at the Media Center in Malcolm A. Love Library, San Diego State University.
Author: Brendan Calhoun Kyle
Publisher:
ISBN:
Category : Anostraca
Languages : en
Pages : 0
Get Book Here
Book Description
Wetlands are rapidly being lost from human impacts, and in California the effects are especially dramatic. Sensitive wetland habitats, like vernal pools, are at risk of being lost. Vernal pools are home to many endemic species, so the conservation of vernal pools is critical to maintaining California's biodiversity. Understanding the ecological, physiological, and genetic aspects of a species is important when implementing critical management for the persistence of endangered species. The longhorn fairy shrimp, Branchinecta longiantenna, is one of several endemic and endangered inhabitants of California's vernal pools. Longhorn fairy shrimp distribution is quite restricted, they are found in only three regions of California (Altamont Pass, Kesterson National Wildlife Refuge, and Carrizo Plains). Little is known about their ecology, physiology, and genetics. My research aimed to establish a framework of our genetic understanding of longhorn fairy shrimp throughout its range. I analyzed population genomic data for samples collected from each region to determine population structure and variation. I found evidence for phylogeographic structure associated with isolated regions from pairwise estimates of population differentiation, principal component analysis, and phylogenetics. Differentiation within regions was generally low, but much higher at Altamont Pass, which is likely due to differences in population size and dispersal. This is also reflected in levels of heterozygosity, which were much lower in the Altamont Pass pool than any other. These differences stress that management programs should use evolutionary significant units that distinguish longhorn fairy shrimp by their respective regions when developing conservation plans for this species.
Author: John Alexander Eads
Publisher:
ISBN:
Category :
Languages : en
Pages : 136
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 862
Get Book Here
Book Description
Author: Carol W. Witham
Publisher:
ISBN:
Category : Reference
Languages : en
Pages : 302
Get Book Here
Book Description
Author: Darold Batzer
Publisher: Springer
ISBN: 3319249789
Category : Science
Languages : en
Pages : 647
Get Book Here
Book Description
Wetlands are among the world’s most valuable and most threatened habitats, and in these crucially important ecosystems, the invertebrate fauna holds a focal position. Most of the biological diversity in wetlands is found within resident invertebrate assemblages, and those invertebrates are the primary trophic link between lower plants and higher vertebrates (e.g. amphibians, fish, and birds). As such, most scientists, managers, consultants, and students who work in the world’s wetlands should become better informed about the invertebrate components in their habitats of interest. Our book serves to fill this need by assembling the world’s most prominent ecologists working on freshwater wetland invertebrates, and having them provide authoritative perspectives on each the world’s most important freshwater wetland types. The initial chapter of the book provides a primer on freshwater wetland invertebrates, including how they are uniquely adapted for life in wetland environments and how they contribute to important ecological functions in wetland ecosystems. The next 15 chapters deal with invertebrates in the major wetlands across the globe (rock pools, alpine ponds, temperate temporary ponds, Mediterranean temporary ponds, turloughs, peatlands, permanent marshes, Great Lakes marshes, Everglades, springs, beaver ponds, temperate floodplains, neotropical floodplains, created wetlands, waterfowl marshes), each chapter written by groups of prominent scientists intimately knowledgeable about the individual wetland types. Each chapter reviews the relevant literature, provides a synthesis of the most important ecological controls on the resident invertebrate fauna, and highlights important conservation concerns. The final chapter synthesizes the 15 habitat-based chapters, providing a macroscopic perspective on natural variation of invertebrate assemblage structure across the world’s wetlands and a paradigm for understanding how global variation and environmental factors shape wetland invertebrate communities.
Author: Ketan Vasant Patel
Publisher:
ISBN: 9780355936957
Category : Branchinecta
Languages : en
Pages : 118
Get Book Here
Book Description
Driven by landscape alteration and the introduction of non-natives through human activities, biotic homogenization is thought to be a significant threat to the survival of endemic taxa. Extensive urbanization in southern California, USA, has converted most of the native coastal vernal pool habitat prompting the conservation of native vernal pool species. Habitat alteration associated with urban expansion in this region has extirpated B. sandiegonensis from the majority of its historical habitat. In some artificial basins within the remaining vernal pool habitat, B. sandiegonensis hybridizes with B. lindahli. Hybrids can be identified through both morphology and newly developed genetic characters (Patel et al. 2017). By using both morphological and genomic hybrid indices, researchers and habitat managers will obtain a relatively holistic perspective on the hybridization process. This not only helps to identify populations where a large-scale introduction of B. lindahli has occurred, but also to perhaps predict the future trajectory of species and hybrid distributions.
Author:
Publisher:
ISBN:
Category : Biology
Languages : en
Pages : 118
Get Book Here
Book Description
Patterns of dispersal and gene-flow in freshwater invertebrates have often been difficult to interpret. Despite the assumed high potential for dispersal, populations of freshwater invertebrates display high genetic differentiation over small distances. There have been several explanations posed for this gene flow dispersal paradox, including strong priority effects or low realized dispersal. This study explores the spatial genetic structure of the freshwater invertebrate Branchinecta lynchi, a threatened vernal pool inhabitant, at two scales with a goal to determine the scale at which gene flow is important in shaping these patterns. Vernal pools were sampled at two different localities the San Luis National Wildlife Refuge Complex and a preserve adjacent to the University of California, Merced. Individuals were genotyped using both the mitochondrial cytochrome oxidase I subunit (COI) and nuclear amplified fragment length polymorphisms (AFLPs). Pairwise Fst values showed that genetic structure for this species was high, however, the only geographic pattern that emerged was isolation by distance at the local scale for the COI marker. Discrepancies between mitochondrial and AFLP markers may be explained several ways, including genotyping error, sex-biased dispersal and/or the longer time to equilibrium of the nuclear genome. These results suggest that gene flow is important at the local scale, at least for mitochondrial DNA, while historical colonization patterns are likely maintained at the regional scale by priority effects. I infer that maintaining connectivity among vernal pool complexes through local dispersal vectors should be a management priority.
