scholarly journals Low genetic diversity in pygmy blue whales is due to climate-induced diversification rather than anthropogenic impacts

2015 ◽  
Vol 11 (5) ◽  
pp. 20141037 ◽  
Author(s):  
Catherine R. M. Attard ◽  
Luciano B. Beheregaray ◽  
K. Curt S. Jenner ◽  
Peter C. Gill ◽  
Micheline-Nicole M. Jenner ◽  
...  
Keyword(s):  
Climate Change ◽  
Genetic Diversity ◽  
Anthropogenic Impacts ◽  
Future Climate Change ◽  
Evolutionary Divergence ◽  
Balaenoptera Musculus ◽  
Low Genetic Diversity ◽  
Low Levels ◽  
Analytical Approaches ◽  
Blue Whales

Unusually low genetic diversity can be a warning of an urgent need to mitigate causative anthropogenic activities. However, current low levels of genetic diversity in a population could also be due to natural historical events, including recent evolutionary divergence, or long-term persistence at a small population size. Here, we determine whether the relatively low genetic diversity of pygmy blue whales ( Balaenoptera musculus brevicauda ) in Australia is due to natural causes or overexploitation. We apply recently developed analytical approaches in the largest genetic dataset ever compiled to study blue whales (297 samples collected after whaling and representing lineages from Australia, Antarctica and Chile). We find that low levels of genetic diversity in Australia are due to a natural founder event from Antarctic blue whales ( Balaenoptera musculus intermedia ) that occurred around the Last Glacial Maximum, followed by evolutionary divergence. Historical climate change has therefore driven the evolution of blue whales into genetically, phenotypically and behaviourally distinct lineages that will likely be influenced by future climate change.

scholarly journals Cembranoids of Soft Coral Sarcophyton from Acidified Coral Reef Environment at Shallow Water CO2 vents in Volcano Island, Banda Neira, Indonesia

2017 ◽  
Vol 12 (1) ◽  
Author(s):  
Hedi Indra Januar ◽  
Neviaty Putri Zamani ◽  
Dedi Soedharma ◽  
Ekowati Chasanah
Keyword(s):  
Climate Change ◽  
Genetic Diversity ◽  
Ocean Acidification ◽  
High Performance ◽  
Soft Coral ◽  
Future Climate Change ◽  
Isolation And Identification ◽  
Reef Environment ◽  
Low Genetic Diversity ◽  
Coral Reef Environment

Cembranoid content in soft coral is known as a chemotype that relate with genotype and environment. This research aimed to characterize the cembranoid Sarcophyton soft coral from the reef that acidified by CO2 volcanic vents (pHT 7.8) at Volcano Islands waters, Banda-Neira (Indonesia), as a means of predicting the future impact of ocean acidification to the genetic diversity of Sarcophyton soft coral. 30 random colonies were taken, combined, and extracted with ethanol. Cembranoid isolation and identification had been done by high performance liquid chromatography and spectrometry techniques. Results of the study found sarcophytol derivatives (sarcophytol A, 11,12-epoxy sarcophytol A, sarcophytol B, and sarcophytol M) as the only chemotype in the sample. This may suggest low genetic diversity in the observed Sarcophyton sample. Therefore, it may suggest that even soft coral is known to be resilient to future acidification pressures, the genetic diversity or the production of diverse cytotoxic metabolite may be hampered due to ocean acidification in future climate change adaptation.

scholarly journals Genetic diversity of rice stem borer (Chilo suppressalis Walker) from Northern Iran and comparison with other countries

2016 ◽  
Vol 48 (3) ◽  
pp. 360 ◽  
Author(s):  
M. Shayanmehr ◽  
E. Yoosefi-Lafooraki
Keyword(s):  
Genetic Diversity ◽  
Stem Borer ◽  
Chilo Suppressalis ◽  
Mazandaran Province ◽  
Northern Iran ◽  
Low Genetic Diversity ◽  
High Gene ◽  
Major Pest ◽  
Different Populations ◽  
Low Levels

Rice striped stem borer, <em>Chilo suppressalis</em> Walker (Lepidoptera: Crambidae) is considered the major pest of rice in Iran. Because of the serious damage on rice in Northern Iran, the present study was conducted to investigate genetic diversity within populations of <em>C. suppressalis</em>, from Mazandaran using a template of cytochrome oxidase I gene, 750 bps, (<em>COI</em>). Later the haplotypes from Iran were compared with those found in other countries. According to the results of this study, there is very low genetic diversity (two haplotypes) among different populations of this pest in populations of Northern Iran. The genetic similarity and low levels of genetic diversity of these populations suggest that the pest colonization occurred relatively recently and there is high gene flow between these populations of the province. In addition, haplotypes of Mazandaran province are different with those found in other countries. The similarity of Iranian population (Simorgh) with one population from China indicated that China might be the origin of <em>C. suppresalis</em>.

scholarly journals Unusually Low Levels of Genetic Variation among Giardia lamblia Isolates

2007 ◽  
Vol 6 (8) ◽  
pp. 1421-1430 ◽  
Author(s):  
Smilja Teodorovic ◽  
John M. Braverman ◽  
Heidi G. Elmendorf
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Giardia Lamblia ◽  
Diarrheal Disease ◽  
Regulation Of Gene Expression ◽  
Genetic Exchange ◽  
Disease Etiology ◽  
Noncoding Regions ◽  
Low Genetic Diversity ◽  
Low Levels

ABSTRACT Giardia lamblia, an intestinal pathogen of mammals, including humans, is a significant cause of diarrheal disease around the world. Additionally, the parasite is found on a lineage which separated early from the main branch in eukaryotic evolution. The extent of genetic diversity among G. lamblia isolates is insufficiently understood, but this knowledge is a prerequisite to better understand the role of parasite variation in disease etiology and to examine the evolution of mechanisms of genetic exchange among eukaryotes. Intraisolate genetic variation in G. lamblia has never been estimated, and previous studies on interisolate genetic variation have included a limited sample of loci. Here we report a population genetics study of intra- and interisolate genetic diversity based on six coding and four noncoding regions from nine G. lamblia isolates. Our results indicate exceedingly low levels of genetic variation in two out of three G. lamblia groups that infect humans; this variation is sufficient to allow identification of isolate-specific markers. Low genetic diversity at both coding and noncoding regions, with an overall bias towards synonymous substitutions, was discovered. Surprisingly, we found a dichotomous haplotype structure in the third, more variable G. lamblia group, represented by a haplotype shared with one of the homogenous groups and an additional group-specific haplotype. We propose that the distinct patterns of genetic-variation distribution among lineages are a consequence of the presence of genetic exchange. More broadly, our findings have implications for the regulation of gene expression, as well as the mode of reproduction in the parasite.

Genetic diversity and structure of blue whales (Balaenoptera musculus) in Australian feeding aggregations

2010 ◽  
Vol 11 (6) ◽  
pp. 2437-2441 ◽  
Author(s):  
Catherine R. M. Attard ◽  
Luciano B. Beheregaray ◽  
Curt Jenner ◽  
Peter Gill ◽  
Micheline Jenner ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Balaenoptera Musculus ◽  
Genetic Diversity And Structure ◽  
Blue Whales

Genetic diversity in caribou linked to past and future climate change

2013 ◽  
Vol 4 (2) ◽  
pp. 132-137 ◽  
Author(s):  
Glenn Yannic ◽  
Loïc Pellissier ◽  
Joaquín Ortego ◽  
Nicolas Lecomte ◽  
Serge Couturier ◽  
...  
Keyword(s):  
Climate Change ◽  
Genetic Diversity ◽  
Future Climate ◽  
Future Climate Change

scholarly journals Macrofaunal diversity gradients in Antarctic rocky benthic communities: Effects of glaciers and depth

2018 ◽  
Author(s):  
Luis Miguel Pardo ◽  
Ignacio Garrido ◽  
Paulina Bruning ◽  
Charlotte Carrier ◽  
Rossana Reveco ◽  
...  
Keyword(s):  
Climate Change ◽  
Species Diversity ◽  
Salinity Tolerance ◽  
Environmental Changes ◽  
Anthropogenic Impacts ◽  
Benthic Communities ◽  
Future Climate Change ◽  
Climate Change Scenarios ◽  
Rocky Subtidal ◽  
Diversity Gradients

Western Antarctic shows one of the fastest responses to climate change on Earth. Glacier meltdown and freshening are perhaps the most conspicuous evidence of anthropogenic impacts, that together with ice scouring can strongly modify benthic communities. The spatial extension of these impacts has been rarely explored in rocky subtidal environments. This study describes changes in benthic communities across glacier and bathymetric gradient in Fildes Bay, Antarctica. Suction samples were taken from four sites at increasing distance from the Collin glacier (0 - 2.5 – 5 - 7 km) and three depths (5 – 10 - 15 m). Macrofaunal diversity increased with depth across all distances from the glacier; these changes were associated with the increase in diversity of amphipods and echinoderms. The lowest and highest species diversity occurred at zero and two km from the glacier, indicating a strong, but localized, glacier effect. Variation in salinity tolerance and the abundance of key habitat forming algae could explain the spatial variation in these communities. This result remarks the importance of facilitation as a structuring force in Antarctic benthic communities. We suggest that the fate of communities in future climate-change scenarios will depend on how habitat-forming species respond to these environmental changes.

scholarly journals Microsatellite analysis of genetic diversity and structure of Bruguiera gymnorrhiza and Kandelia obovate

2018 ◽  
Vol 52 ◽  
pp. 00027 ◽  
Author(s):  
Mohammad Basyuni ◽  
Shigeyuki Baba ◽  
Hirosuke Oku
Keyword(s):  
Genetic Diversity ◽  
Allelic Diversity ◽  
Geographic Range ◽  
Microsatellite Analysis ◽  
Bruguiera Gymnorrhiza ◽  
Low Genetic Diversity ◽  
Genetic Diversity And Structure ◽  
Low Levels ◽  
High Level ◽  
F Statistics

Microsatellite loci were used for estimating genetic diversity and structure for three populations of B. gymnorrhiza and K. obovata (Rhizophoracea) in Okinawa, Japan. Thirty propagules of individual samples representing the population of both species were genotyped at five microsatellites. The level of observed heterozygosity (HO) was observed for several population, overall loci, ranged 0.422-0.800 with an average 0.627 for B. gymnorrhiza and 0.477-0.822 with an average 0.665 for K. obovata, indicating both species had relatively low genetic diversity. Both species showed low levels of allelic diversity, 3-5 and 3-5 alleles per locus, respectively. Gene diversitywas also maintained within populations (HS: 0.741 and 0.954). Additionally, an analysis of molecular variance (AMOVA) based on the immeasurable alleles model (F-statistics), for B. gymnorrhiza and K. obovata found that most of the variation resided within individuals in the total populations, i.e. 79.78 % and 69.90 % respectively, and among individuals within populations, i.e.14.30 % and 27.95 % respectively. There was little variation between populations, i.e. 5.92 % and 2.15 % for B. gymnorrhiza and K. obovata, respectively. The high-level genetic differentiation within individuals and populations both species may be due to the geographic range of the species, mating system, and environmental factors.

Towards an improved understanding of hydrological change – linking hydrologic metrics and multiple change point tests

2018 ◽  
Vol 10 (4) ◽  
pp. 743-758 ◽  
Author(s):  
T. T. Vu ◽  
J. Kiesel ◽  
B. Guse ◽  
N. Fohrer
Keyword(s):  
Climate Change ◽  
Change Point ◽  
Anthropogenic Impacts ◽  
Climate Change Impacts ◽  
Change Points ◽  
Future Climate Change ◽  
Anthropogenic Changes ◽  
Hydrological Changes ◽  
Discharge Regime ◽  
Hydrological System

Abstract Understanding the connections between climate, anthropogenic impacts, and hydrology is fundamental for assessing future climate change. However, a comprehensive methodology is lacking to understand significant changes in the discharge regime and their causes. We propose an approach that links change point tests with hydrologic metrics applied to two Vietnamese catchments where both climatic and anthropogenic changes are observed. The change points in discharge series are revealed by six widely used change point tests. Then, 171 hydrologic metrics are investigated to evaluate all possible hydrological changes that occurred between the pre- and post-change point period. The tests showed sufficient capabilities to detect hydrological changes caused by precipitation alterations and damming. Linking the change point tests to the hydrological metrics had three benefits: (1) the significance of each detected change point was evaluated, (2) we found which test responds to which hydrologic metric, and (3) we were able to disentangle the hydrological impacts of the climatic and anthropogenic changes. Due to its objectivity, the presented method can improve the interpretation of anthropogenic changes and climate change impacts on the hydrological system.

scholarly journals Phylogeography and niche modelling: reciprocal enlightenment

Mammalia ◽  
2019 ◽  
Vol 84 (1) ◽  
pp. 10-25 ◽  
Author(s):  
Govan Pahad ◽  
Claudine Montgelard ◽  
Bettine Jansen van Vuuren
Keyword(s):  
Climate Change ◽  
Genetic Diversity ◽  
Ecological Niche ◽  
Spatial Genetic Structure ◽  
Distribution Patterns ◽  
Future Climate ◽  
Future Climate Change ◽  
Environmental Niche ◽  
Climate Data ◽  
Niche Modelling

Abstract Phylogeography examines the spatial genetic structure of species. Environmental niche modelling (or ecological niche modelling; ENM) examines the environmental limits of a species’ ecological niche. These two fields have great potential to be used together. ENM can shed light on how phylogeographical patterns develop and help identify possible drivers of spatial structure that need to be further investigated. Specifically, ENM can be used to test for niche differentiation among clades, identify factors limiting individual clades and identify barriers and contact zones. It can also be used to test hypotheses regarding the effects of historical and future climate change on spatial genetic patterns by projecting niches using palaeoclimate or future climate data. Conversely, phylogeographical information can populate ENM with within-species genetic diversity. Where adaptive variation exists among clades within a species, modelling their niches separately can improve predictions of historical distribution patterns and future responses to climate change. Awareness of patterns of genetic diversity in niche modelling can also alert conservationists to the potential loss of genetically diverse areas in a species’ range. Here, we provide a simplistic overview of both fields, and focus on their potential for integration, encouraging researchers on both sides to take advantage of the opportunities available.

scholarly journals Selection of progenitors for increase in oil content in soybean

Revista CERES ◽  
2016 ◽  
Vol 63 (5) ◽  
pp. 661-667 ◽  
Author(s):  
Josiane Isabela da Silva Rodrigues ◽  
Klever Márcio Antunes Arruda ◽  
Newton Deniz Piovesan ◽  
Everaldo Gonçalves de Barros ◽  
Maurilio Alves Moreira
Keyword(s):  
Genetic Diversity ◽  
Glycine Max ◽  
Genetic Distance ◽  
Oil Content ◽  
Infrared Spectrometry ◽  
Low Genetic Diversity ◽  
Soybean Genotypes ◽  
Glycine Max L ◽  
Low Levels ◽  
Selection Of

ABSTRACT The low genetic diversity brings limitation to breeding, because genetically similar genotypes share alleles in common, causing little complementarity and low vigor due to the low levels of heterozygosity in crosses. The objective of this work was to analyze the oil content and genetic diversity of soybean genotypes (Glycine max (L.) Merrill) based on QTL regions of this trait for choice of progenitors for increase in oil content. Twenty-two genotypes with wide variation in oil content, including cultivars with high oil contents, were cultivated in different Brazilian conditions and the oil content of the grains was quantified by infrared spectrometry. Microsatellite markers selected based on QTL regions for oil content in soybean were analyzed to estimate the genetic diversity. In these studies, a wide variation in oil content (17.28-23.01%) and a reasonable diversity among the genotypes were observed, being PI181544 the most divergent genotype, followed by Suprema. The genotypes PI371610/Suprema and Suprema/CD01RR8384 showed genetic distance and higher oil contents in the grains, while the cultivars Suprema and CD01RR8384 had the highest oil contents and proved to be little genetically related. These genotypes are promising progenitors for selection of high oil content in soybean.

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