scholarly journals Genetic structure and diversity of the mustard hill coral Porites astreoides along the Florida Keys reef tract

2021 ◽  
Vol 51 (4) ◽  
Author(s):  
Dominique N. Gallery ◽  
Michelle L. Green ◽  
Ilsa B. Kuffner ◽  
Elizabeth A. Lenz ◽  
Lauren T. Toth
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Genetic Relatedness ◽  
Florida Keys ◽  
Genetic Population ◽  
High Genetic Diversity ◽  
Western Atlantic ◽  
Porites Astreoides ◽  
Single Well ◽  
Reef Tract

AbstractIncreases in local and global stressors have led to major declines in coral populations throughout the western Atlantic. While abundances of other species have declined, however, the relative abundance of the mustard hill coral, Porites astreoides, has increased. Porites astreoides is relatively resilient to some stressors, and because of its mixed reproductive strategies, its populations often recover quickly following disturbances. The ability for P. astreoides to continue as a potential “winner” in western Atlantic reefs relies on maintaining sufficient genetic variation within populations to support acclimatization and adaptation to current and future environmental change. Without high genetic diversity and gene flow within the population, it would have limited capacity for adaptation and the species’ competitive advantages could be short-lived. In this study, we determined the genetic relatedness of 37 P. astreoides colonies at four shallow reefs along the offshore Florida Keys Reef Tract (FKRT), a region particularly hard-hit by recent disturbances. Using previously designed microsatellite markers, we determined the genetic diversity and connectivity of individuals among and between sites. Our results suggest that the FKRT likely contains a single, well-mixed genetic population of P. astreoides, with high levels of gene flow and evidence for larval migration throughout the region. This suggests that regional populations of P. astreoides likely have a higher chance of maintaining resilience than many other western Atlantic species as they face current and future disturbances.

scholarly journals Range reduction of the Oblong Rocksnail, Leptoxis compacta, shapes riverscape genetic patterns

2020 ◽  
Author(s):  
Aaliyah D. Wright ◽  
Nicole L. Garrison ◽  
Ashantye’ S. Williams ◽  
Paul D. Johnson ◽  
Nathan V. Whelan
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Human Impacts ◽  
Isolation By Distance ◽  
Extinction Risk ◽  
River System ◽  
High Genetic Diversity ◽  
Range Contraction ◽  
Genetic Patterns ◽  
Cahaba River

AbstractMany freshwater gastropod species face extinction, including 79% of species in the family Pleuroceridae. The Oblong Rocksnail, Leptoxis compacta, is a narrow range endemic pleurocerid from the Cahaba River basin in central Alabama that has seen rapid range contraction in the last 100 years. Such a decline is expected to negatively affect genetic diversity in the species. However, precise patterns of genetic variation and gene flow across the restricted range of L. compacta are unknown. This lack of information limits our understanding of human impacts on the Cahaba River system and Pleuroceridae. Here, we show that L. compacta has likely seen a species-wide decline in genetic diversity, but remaining populations have relatively high genetic diversity. We also report a contemporary range extension compared to the last published survey. Leptoxis compacta does not display an isolation by distance pattern, contrasting patterns seen in many riverine taxa. Our findings also indicate that historical range contraction has resulted in the absence of common genetic patterns seen in many riverine taxa like isolation by distance as the small distribution of L. compacta allows for relatively unrestricted gene flow across its remaining range despite limited dispersal abilities. Two collection sites had higher genetic diversity than others, and broodstock sites for future captive propagation and reintroduction efforts should utilize sites identified here as having the highest genetic diversity. Broadly, our results support the hypothesis that range contraction will result in the reduction of species-wide genetic diversity, and common riverscape genetic patterns cannot be assumed to be present in species facing extinction risk.

scholarly journals Range reduction of Oblong Rocksnail, Leptoxis compacta, shapes riverscape genetic patterns

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9789
Author(s):  
Aaliyah D. Wright ◽  
Nicole L. Garrison ◽  
Ashantye’ S. Williams ◽  
Paul D. Johnson ◽  
Nathan V. Whelan
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Human Impacts ◽  
Isolation By Distance ◽  
Extinction Risk ◽  
River System ◽  
High Genetic Diversity ◽  
Range Contraction ◽  
Genetic Patterns ◽  
Cahaba River

Many freshwater gastropod species face extinction, including 79% of species in the family Pleuroceridae. The Oblong Rocksnail, Leptoxis compacta, is a narrow range endemic pleurocerid from the Cahaba River basin in central Alabama that has seen rapid range contraction in the last 100 years. Such a decline is expected to negatively affect genetic diversity in the species. However, precise patterns of genetic variation and gene flow across the restricted range of L. compacta are unknown. This lack of information limits our understanding of human impacts on the Cahaba River system and Pleuroceridae. Here, we show that L. compacta has likely seen a species-wide decline in genetic diversity, but remaining populations have relatively high genetic diversity. We also report a contemporary range extension compared to the last published survey. Our findings indicate that historical range contraction has resulted in the absence of common genetic patterns seen in many riverine taxa like isolation by distance as the small distribution of L. compacta allows for relatively unrestricted gene flow across its remaining range despite limited dispersal abilities. Two collection sites had higher genetic diversity than others, and broodstock sites for future captive propagation and reintroduction efforts should utilize sites identified here as having the highest genetic diversity. Broadly, our results support the hypothesis that range contraction will result in the reduction of species-wide genetic diversity, and common riverscape genetic patterns cannot be assumed to be present in species facing extinction risk.

Gene flow from multiple sources maintains high genetic diversity and stable population history of Common MoorhenGallinula chloropusin China

Ibis ◽  
2018 ◽  
Vol 160 (4) ◽  
pp. 855-869 ◽  
Author(s):  
Luzhang Ruan ◽  
Wei Xu ◽  
Yuqing Han ◽  
Chaoying Zhu ◽  
Bicai Guan ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Population History ◽  
Stable Population ◽  
Multiple Sources ◽  
High Genetic Diversity ◽  
History Of

scholarly journals Gene flow between diploid and tetraploid junipers - two contrasting evolutionary pathways in two Juniperus populations

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Perla Farhat ◽  
Sonja Siljak-Yakovlev ◽  
Nicolas Valentin ◽  
Carlos Fabregat ◽  
Silvia Lopez-Udias ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Ploidy Level ◽  
High Genetic Diversity ◽  
Iberian Range ◽  
In The Wild ◽  
Evolutionary Pathways

Abstract Background Gene flow and polyploidy have been found to be important in Juniperus evolution. However, little evidence has been published elucidating the association of both phenomena in juniper taxa in the wild. Two main areas were studied in Spain (Eastern Iberian Range and Sierra de Baza) with both diploid and tetraploid taxa present in sympatry. Gene flow and ploidy level were assessed for these taxa and the resulted offspring. Results Twenty-two allo-triploid hybrids between J. sabina var. sabina and J. thurifera were found in the Eastern Iberian Range population. However, in the Sierra de Baza population no triploids were found. Instead, 18 allo-tetraploid hybrids between two tetraploid taxa: J. sabina var. balkanensis and J. thurifera were discovered. High genetic diversity was exhibited among the tetraploid hybrids at Sierra de Baza, in contrast to the genetically identical triploid hybrids at the Eastern Iberian Range; this suggests meiotic difficulties within the triploid hybrids. In addition, unidirectional gene flow was observed in both studied areas. Conclusion Polyploidy and hybridization can be complementary partners in the evolution of Juniperus taxa in sympatric occurrences. Juniperus was shown to be an ideal coniferous model to study these two phenomena, independently or in concert.

scholarly journals Pollen-mediated gene flow ensures connectivity among spatially discrete sub-populations of Phalaenopsis pulcherrima, a tropical food-deceptive orchid

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Zhe Zhang ◽  
Stephan W. Gale ◽  
Ji-Hong Li ◽  
Gunter A. Fischer ◽  
Ming-Xun Ren ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Polynomial Regression ◽  
Genetic Erosion ◽  
Population Level ◽  
Hainan Island ◽  
Paternity Analysis ◽  
Genetic Structuring ◽  
Long Distance ◽  
High Genetic Diversity

Abstract Background Gene flow in plants via pollen and seeds is asymmetrical at different geographic scales. Orchid seeds are adapted to long-distance wind dispersal but pollinium transfer is often influenced by pollinator behavior. We combined field studies with an analysis of genetic diversity among 155 physically mapped adults and 1105 F1 seedlings to evaluate the relative contribution of pollen and seed dispersal to overall gene flow among three sub-populations of the food-deceptive orchid Phalaenopsis pulcherrima on Hainan Island, China. Results Phalaenopsis pulcherrima is self-sterile and predominantly outcrossing, resulting in high population-level genetic diversity, but plants are clumped and exhibit fine-scale genetic structuring. Even so, we detected low differentiation among sub-populations, with polynomial regression analysis suggesting gene flow via seed to be more restricted than that via pollen. Paternity analysis confirmed capsules of P. pulcherrima to each be sired by a single pollen donor, probably in part facilitated by post-pollination stigma obfuscation, with a mean pollen flow distance of 272.7 m. Despite limited sampling, we detected no loss of genetic diversity from one generation to the next. Conclusions Outcrossing mediated by deceptive pollination and self-sterility promote high genetic diversity in P. pulcherrima. Long-range pollinia transfer ensures connectivity among sub-populations, offsetting the risk of genetic erosion at local scales.

scholarly journals Genetic population structure of the blue sea star Linckia laevigata in the Visayas (Philippines)

2015 ◽  
pp. 1-7 ◽  
Author(s):  
Diana Sr Alcazar ◽  
Marc Kochzius
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Gene Flow ◽  
Comparative Analysis ◽  
Marine Invertebrates ◽  
Genetic Population Structure ◽  
Sea Star ◽  
Genetic Population ◽  
Gene Coi ◽  
Linckia Laevigata

Coral reef associated marine invertebrates, such as the blue sea starLinckia laevigata, have a life history with two phases: sedentary adults and planktonic larvae. On the one hand it is hypothesised that the long pelagic larval duration facilitates large distance dispersal. On the other hand, complex oceanographic and geographic characteristics of the Visayan seascape could cause isolation of populations. The study aims to investigate the genetic diversity, genetic population structure and gene flow inL. laevigatato reveal connectivity among populations in the Visayas. The analysis is based on partial sequences (626 bp in length) of the mitochondrial cytochrome oxidase I gene (COI) from 124 individuals collected from five localities in the Visayas. A comparative analysis of these populations with populations from the Indo-Malay Archipelago (IMA) published previously is also presented. Genetic diversity was high (h = 0.98, π = 1.6%) and comparable with preceding studies. Analyses of molecular variance (AMOVA) revealed a lack of spatial population differentiation among sample sites in the Visayas (ΦST-value = 0.009;P > 0.05). The lack of genetic population structure indicates high gene flow among populations ofL. laevigatain the Visayas. Comparative analysis with data from the previous study indicates high connectivity of the Visayas with the central part of the IMA.

scholarly journals Genetic diversity, structure and gene flow of migratory barren-ground caribou (Rangifer tarandus groenlandicus) in Canada

Rangifer ◽  
2016 ◽  
Vol 36 (1) ◽  
pp. 1 ◽  
Author(s):  
Keri McFarlane ◽  
Anne Gunn ◽  
Mitch Campbell ◽  
Mathieu Dumond ◽  
Jan Adamczewski ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Gene Flow ◽  
Rangifer Tarandus ◽  
Continuous Distribution ◽  
Effective Population ◽  
Genetic Population ◽  
Barren Ground ◽  
Cyclic Changes ◽  
Rangifer Tarandus Groenlandicus

Migratory barren-ground caribou (Rangifer tarandus groenlandicus) provide an opportunity to examine the genetic population structure of a migratory large mammal whose movements and distribution, in some instances, have not been heavily influenced by human activities that result in habitat loss or fragmentation. These caribou have likely reached large effective population sizes since their rapid radiation during the early Holocene despite cyclic changes in abundance. Migratory barren-ground caribou are managed as discrete subpopulations. We investigated genetic variation among those subpopulations to determine the patterns of genetic diversity within and among them, and the implications for long-term persistence of caribou. We identified three distinct genetic clusters across the Canadian arctic tundra: the first cluster consisted of all fully-continental migratory barren-ground subpopulations; the second cluster was the Dolphin and Union caribou; and the third cluster was caribou from Southampton Island. The Southampton Island caribou are especially genetically distinct from the other barren-ground type caribou. Gene flow among subpopulations varied across the range. Occasional gene flow across the sea-ice is likely the reason for high levels of genetic variation in the Dolphin and Union subpopulation, which experienced very low numbers in the past. These results suggest that for most migratory caribou subpopulations, connectivity among subpopulations plays an important role in maintaining natural genetic diversity. Our analyses provide insight into the levels of microsatellite genetic diversity and patterns of gene flow that may be common to large subpopulations that historically had a continuous distribution across a large continental range. These data can also be used as a benchmark to compare the effects of habitat fragmentation and bottlenecks on other large caribou populations.

scholarly journals Physiological Differences in Bleaching Response of the Coral Porites astreoides Along the Florida Keys Reef Tract During High-Temperature Stress

2021 ◽  
Vol 8 ◽  
Author(s):  
Elizabeth Ann Lenz ◽  
Lucy A. Bartlett ◽  
Anastasios Stathakopoulos ◽  
Ilsa B. Kuffner
Keyword(s):  
Heat Stress ◽  
High Temperature ◽  
Florida Keys ◽  
High Temperature Stress ◽  
Geologic History ◽  
Reef Management ◽  
Porites Astreoides ◽  
Dry Tortugas ◽  
Bleaching Response ◽  
Reef Tract

The Florida Keys reef tract (FKRT) has a unique geological history wherein Holocene sea-level rise and bathymetry interacted, resulting in a reef-building system with notable spatial differences in reef development. Overprinted on this geologic history, recent global and local stressors have led to degraded reefs dominated by fleshy algae, soft corals, and sponges. Here, we assessed how coral physiology (calcification rate, tissue thickness, reproduction, symbiosis, and bleaching) varies seasonally (winter vs. summer) and geographically using 40 colonies of the mustard hill coral Porites astreoides from four sites across 350 km along the FKRT from 2015 to 2017. The study coincided with a high-temperature event in late summer 2015 that caused heterogeneous levels of coral bleaching across sites. Bleaching severity differed by site, with bleaching response more aligned with heat stress retroactively calculated from local degree heating weeks than those predicted by satellites. Despite differences in temperature profiles and bleaching severity, all colonies hosted Symbiodiniaceae of the same genus (formerly Clade A and subtypes). Overall, P. astreoides at Dry Tortugas National Park, the consistently coolest site, had the highest calcification rates, symbiont cell densities, and reproductive potential (all colonies were reproductive, with most planula larvae per polyp). Corals at Dry Tortugas and Fowey Rocks Light demonstrated strong seasonality in net calcification (higher in summer) and did not express visual or partial-mortality responses from the bleaching event; in contrast, colonies in the middle and southern part of the upper keys, Sombrero Key and Crocker Reef, demonstrated similar reduced fitness from bleaching, but differential recovery trajectories following the heat stress. Identifying reefs, such as Dry Tortugas and possibly Fowey Rocks Light that may serve as heat-stress refugia, is important in selecting candidate sites for adaptive reef-management strategies, such as selective propagation and assisted gene flow, to increase coral-species adaptation to ocean warming.

scholarly journals Distribution and population structure in the naked goby Gobiosoma bosc (Perciformes: Gobiidae) along a salinity gradient in two western Atlantic estuaries

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5380 ◽  
Author(s):  
Christopher S. Moore ◽  
Matthew J. Ruocchio ◽  
April M.H. Blakeslee
Keyword(s):  
Genetic Diversity ◽  
North Carolina ◽  
Population Structure ◽  
Gene Flow ◽  
Salinity Gradient ◽  
Western Atlantic ◽  
Widespread Species ◽  
Naked Goby ◽  
Gobiosoma Bosc ◽  
Scale Population

Many species of fish produce larvae that undergo a prolonged dispersal phase. However, evidence from a number of recent studies on demersal fishes suggests that the dispersal of propagules may not be strongly correlated with gene flow. Instead, other factors like larval behavior and the availability of preferred settlement habitat may be more important to maintaining population structure. We used an ecologically important benthic fish species, Gobiosoma bosc (naked goby), to investigate local and regional scale population structure and gene flow along a salinity gradient (∼3 ppt to ∼18 ppt) in two North Carolina estuaries. G. bosc is an abundant and geographically widespread species that requires complex but patchy microhabitat (e.g. oyster reefs, rubble, woody debris) for reproduction and refuge. We sequenced 155 fish from 10 sites, using a common barcoding gene (COI). We also included recent sequence data from GenBank to determine how North Carolina populations fit into the larger biogeographic understanding of this species. In North Carolina, we found a significant amount of gene flow within and between estuaries. Our analysis also showed high predicted genetic diversity based upon a large number of rare haplotypes found within many of our sampled populations. Moreover, we detected a number of new haplotypes in North Carolina that had not yet been observed in prior work. Sampling along a salinity gradient did not reveal any significant positive or negative correlations between salinity and genetic diversity, nor the proportion of singleton haplotypes, with the exception of a positive correlation between salinity standard deviation and genetic diversity. We also found evidence that an introduced European population of naked gobies may have originated from an Atlantic source population. Altogether, this system offers a compelling way to evaluate whether factors other than dispersal per se mediate recruitment in an estuarine-dependent species of fish with a larval dispersal phase. It also demonstrates the importance of exploring both smaller and larger scale population structure in marine organisms to better understand local and regional patterns of population connectivity and gene flow.

Genetic diversity and conservation of the endemic tuco-tuco Ctenomys ibicuiensis (Rodentia: Ctenomyidae)

2020 ◽  
Author(s):  
Mayara Delagnelo Medeiros ◽  
Daniel Galiano ◽  
Bruno Busnello Kubiak ◽  
Paula Angélica Roratto ◽  
Thales Renato Ochotorena de Freitas
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Environmental Changes ◽  
Isolation By Distance ◽  
Conservation Status ◽  
Significant Risk ◽  
Structured Populations ◽  
Small Range ◽  
High Genetic Diversity ◽  
Landscape Modification

Abstract Endemic, small range species are susceptible to environmental changes and landscape modification. Understanding genetic diversity and distributional patterns is important for implementation of effective conservation measures. In this context, genetic diversity was evaluated to update the conservation status of an endemic tuco-tuco, Ctenomys ibicuiensis. Phylogeographic and population genetic analyses of mitochondrial DNA and microsatellite loci were carried out using 46 individuals sampled across the species’ distribution. Ctenomys ibicuiensis presented moderate to high genetic diversity and highly structured populations with low levels of gene flow and isolation by distance. Anthropogenic landscape changes threaten this restricted-range tuco-tuco. Considering its limited geographic distribution and highly structured populations with low gene flow, we consider C. ibicuiensis to be at significant risk of extinction.

Sign in / Sign up

Export Citation Format

Share Document