scholarly journals Varied diversification patterns and distinct demographic trajectories in Ethiopian montane forest bird (Aves: Passeriformes) populations separated by the Great Rift Valley

Author(s):  
Joseph Manthey ◽  
Yann Bourgeois ◽  
Yonas Meheretu ◽  
Stephane Boissinot

Taxon-specific characteristics and extrinsic climatic and geological forces may both shape population differentiation and speciation. In geographically and taxonomically focused investigations, differentiation may occur synchronously as species respond to the same external conditions. Conversely, when evolution is investigated in taxa with largely varying traits, population differentiation and speciation is complex and shaped by interactions of Earth’s template and species-specific traits. As such, it is important to characterize evolutionary histories broadly across the tree of life, especially in geographic regions that are exceptionally diverse and under pressures from human activities such as in biodiversity hotspots. Here, using whole-genome sequencing data, we characterize genomic variation in populations of six Ethiopian Highlands forest bird species separated by a lowland biogeographic barrier, the Great Rift Valley (GRV). In all six species, populations on either side of the GRV exhibited significant but varying levels of genetic differentiation. Species’ dispersal ability was negatively correlated with levels of population differentiation. Isolation with migration models indicated varied patterns of population differentiation and connectivity among populations of the focal species. We found that demographic histories—estimated for each individual—varied by both species and population but were consistent between individuals of the same species and sampling region. We found that genomic diversity varied by half an order of magnitude across species, and that this variation could largely be explained by the harmonic mean of effective population size over the past 200,000 years. Overall, we found that even in highly dispersive species like birds, the GRV acts as a substantial biogeographic barrier.

Author(s):  
Joseph Manthey ◽  
Yann Bourgeois ◽  
Yonas Meheretu ◽  
Stephane Boissinot

Taxon-specific characteristics and extrinsic climatic and geological forces may both shape population differentiation and speciation. In geographically and taxonomically focused investigations, differentiation may occur synchronously as species respond to the same external conditions. Conversely, when evolution is investigated in taxa with largely varying traits, population differentiation and speciation is complex and shaped by interactions of Earth’s template and species-specific traits. As such, it is important to characterize evolutionary histories broadly across the tree of life, especially in geographic regions that are exceptionally diverse and under pressures from human activities such as in biodiversity hotspots. Here, using whole-genome sequencing data, we characterize genomic variation in populations of six Ethiopian Highlands forest bird species separated by a lowland biogeographic barrier, the Great Rift Valley (GRV). In all six species, populations on either side of the GRV exhibited significant but varying levels of genetic differentiation. Species with lower dispersal ability generally had higher levels of population differentiation. Divergence dating indicated asynchronous population differentiation histories, with at least three distinct diversification periods. We found that demographic histories—estimated for each individual—varied by both species and population but were consistent between individuals of the same species and sampling region. We found that genomic diversity varied by half an order of magnitude across species, and that this variation could largely be explained by the harmonic mean of effective population size over the past 200,000 years. Overall, we found that even in highly dispersive species like birds, the GRV acts as a substantial biogeographic barrier.


BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Xiaoting Xia ◽  
Shunjin Zhang ◽  
Huaju Zhang ◽  
Zijing Zhang ◽  
Ningbo Chen ◽  
...  

Abstract Background Native cattle breeds are an important source of genetic variation because they might carry alleles that enable them to adapt to local environment and tough feeding conditions. Jiaxian Red, a Chinese native cattle breed, is reported to have originated from crossbreeding between taurine and indicine cattle; their history as a draft and meat animal dates back at least 30 years. Using whole-genome sequencing (WGS) data of 30 animals from the core breeding farm, we investigated the genetic diversity, population structure and genomic regions under selection of Jiaxian Red cattle. Furthermore, we used 131 published genomes of world-wide cattle to characterize the genomic variation of Jiaxian Red cattle. Results The population structure analysis revealed that Jiaxian Red cattle harboured the ancestry with East Asian taurine (0.493), Chinese indicine (0.379), European taurine (0.095) and Indian indicine (0.033). Three methods (nucleotide diversity, linkage disequilibrium decay and runs of homozygosity) implied the relatively high genomic diversity in Jiaxian Red cattle. We used θπ, CLR, FST and XP-EHH methods to look for the candidate signatures of positive selection in Jiaxian Red cattle. A total number of 171 (θπ and CLR) and 17 (FST and XP-EHH) shared genes were identified using different detection strategies. Functional annotation analysis revealed that these genes are potentially responsible for growth and feed efficiency (CCSER1), meat quality traits (ROCK2, PPP1R12A, CYB5R4, EYA3, PHACTR1), fertility (RFX4, SRD5A2) and immune system response (SLAMF1, CD84 and SLAMF6). Conclusion We provide a comprehensive overview of sequence variations in Jiaxian Red cattle genomes. Selection signatures were detected in genomic regions that are possibly related to economically important traits in Jiaxian Red cattle. We observed a high level of genomic diversity and low inbreeding in Jiaxian Red cattle. These results provide a basis for further resource protection and breeding improvement of this breed.


Viruses ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 285
Author(s):  
Cynthia R. Adams ◽  
Vicki S. Blazer ◽  
Jim Sherry ◽  
Robert Scott Cornman ◽  
Luke R. Iwanowicz

Hepatitis B viruses belong to a family of circular, double-stranded DNA viruses that infect a range of organisms, with host responses that vary from mild infection to chronic infection and cancer. The white sucker hepatitis B virus (WSHBV) was first described in the white sucker (Catostomus commersonii), a freshwater teleost, and belongs to the genus Parahepadnavirus. At present, the host range of WSHBV and its impact on fish health are unknown, and neither genetic diversity nor association with fish health have been studied in any parahepadnavirus. Given the relevance of genomic diversity to disease outcome for the orthohepadnaviruses, we sought to characterize genomic variation in WSHBV and determine how it is structured among watersheds. We identified WSHBV-positive white sucker inhabiting tributaries of Lake Michigan, Lake Superior, Lake Erie (USA), and Lake Athabasca (Canada). Copy number in plasma and in liver tissue was estimated via qPCR. Templates from 27 virus-positive fish were amplified and sequenced using a primer-specific, circular long-range amplification method coupled with amplicon sequencing on the Illumina MiSeq. Phylogenetic analysis of the WSHBV genome identified phylogeographical clustering reminiscent of that observed with human hepatitis B virus genotypes. Notably, most non-synonymous substitutions were found to cluster in the pre-S/spacer overlap region, which is relevant for both viral entry and replication. The observed predominance of p1/s3 mutations in this region is indicative of adaptive change in the polymerase open reading frame (ORF), while, at the same time, the surface ORF is under purifying selection. Although the levels of variation we observed do not meet the criteria used to define sub/genotypes of human and avian hepadnaviruses, we identified geographically associated genome variation in the pre-S and spacer domain sufficient to define five WSHBV haplotypes. This study of WSHBV genetic diversity should facilitate the development of molecular markers for future identification of genotypes and provide evidence in future investigations of possible differential disease outcomes.


2021 ◽  
Vol 9 (7) ◽  
pp. 1416
Author(s):  
Karen Leth Nielsen ◽  
Marc Stegger ◽  
Kristoffer Kiil ◽  
Berit Lilje ◽  
Karen Ejrnæs ◽  
...  

Recurrent urinary tract infection (rUTI) remains a major problem for many women and therefore the pursuit for genomic and phenotypic traits which could define rUTI has been ongoing. The present study applied a genomic approach to investigate recurrent urinary tract infections by comparative analyses of recurrent and non-recurrent Escherichia coli isolates from general practice. From whole-genome sequencing data, phylogenetic clustering and genomic traits were studied on a collection of isolates which caused recurrent infection compared to non-recurrent isolates. In addition, genomic variation between the 1st and following infection was studied on a subset of the isolates. Evidence of limited adaptation between the recurrent infections based on single nucleotide polymorphism analyses with a range of 0–13 non-synonymous single nucleotide polymorphisms (SNPs) between the paired isolates. This included an overrepresentation of SNPs in metabolism genes. We identified several genes which were more common in rUTI isolates, including nine fimbrial genes, however, not significantly after false-discovery rate. Finally, the results show that recurrent isolates of the present dataset are not distinctive by variation in the core genome, and thus, did not cluster distinct from non-rUTI isolates in a SNP phylogeny.


2021 ◽  
Vol 13 (2) ◽  
pp. 844
Author(s):  
George Watene ◽  
Lijun Yu ◽  
Yueping Nie ◽  
Jianfeng Zhu ◽  
Thomas Ngigi ◽  
...  

The Kenya Great Rift Valley (KGRV) region unique landscape comprises of mountainous terrain, large valley-floor lakes, and agricultural lands bordered by extensive Arid and Semi-Arid Lands (ASALs). The East Africa (EA) region has received high amounts of rainfall in the recent past as evidenced by the rising lake levels in the GRV lakes. In Kenya, few studies have quantified soil loss at national scales and erosion rates information on these GRV lakes’ regional basins within the ASALs is lacking. This study used the Revised Universal Soil Loss Equation (RUSLE) model to estimate soil erosion rates between 1990 and 2015 in the Great Rift Valley region of Kenya which is approximately 84.5% ASAL. The mean erosion rates for both periods was estimated to be tolerable (6.26 t ha−1 yr−1 and 7.14 t ha−1 yr−1 in 1990 and 2015 respectively) resulting in total soil loss of 116 Mt yr−1 and 132 Mt yr−1 in 1990 and 2015 respectively. Approximately 83% and 81% of the erosive lands in KGRV fell under the low risk category (<10 t ha−1 yr−1) in 1990 and 2015 respectively while about 10% were classified under the top three conservation priority levels in 2015. Lake Nakuru basin had the highest erosion rate net change (4.19 t ha−1 yr−1) among the GRV lake basins with Lake Bogoria-Baringo recording annual soil loss rates >10 t ha−1 yr−1 in both years. The mountainous central parts of the KGRV with Andosol/Nitisols soils and high rainfall experienced a large change of land uses to croplands thus had highest soil loss net change (4.34 t ha−1 yr−1). In both years, forests recorded the lowest annual soil loss rates (<3.0 t ha−1 yr−1) while most of the ASAL districts presented erosion rates (<8 t ha−1 yr−1). Only 34% of all the protected areas were found to have erosion rates <10 t ha−1 yr−1 highlighting the need for effective anti-erosive measures.


1926 ◽  
Vol 68 (2) ◽  
pp. 137
Author(s):  
Sidney Harmer ◽  
Alfred Sharpe ◽  
A. E. Kitson ◽  
F. Dixey

2021 ◽  
Vol 36 ◽  
pp. 100857
Author(s):  
Mathew Herrnegger ◽  
Gabriel Stecher ◽  
Christian Schwatke ◽  
Luke Olang

2015 ◽  
Vol 64 (1) ◽  
pp. 55-61
Author(s):  
Masashi MURAKAMI ◽  
Takao SUZUKI ◽  
Nobuhito OHTE ◽  
Nobumasa ISHII

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ashley Osborne ◽  
Emilia Manko ◽  
Mika Takeda ◽  
Akira Kaneko ◽  
Wataru Kagaya ◽  
...  

AbstractCharacterising the genomic variation and population dynamics of Plasmodium falciparum parasites in high transmission regions of Sub-Saharan Africa is crucial to the long-term efficacy of regional malaria elimination campaigns and eradication. Whole-genome sequencing (WGS) technologies can contribute towards understanding the epidemiology and structural variation landscape of P. falciparum populations, including those within the Lake Victoria basin, a region of intense transmission. Here we provide a baseline assessment of the genomic diversity of P. falciparum isolates in the Lake region of Kenya, which has sparse genetic data. Lake region isolates are placed within the context of African-wide populations using Illumina WGS data and population genomic analyses. Our analysis revealed that P. falciparum isolates from Lake Victoria form a cluster within the East African parasite population. These isolates also appear to have distinct ancestral origins, containing genome-wide signatures from both Central and East African lineages. Known drug resistance biomarkers were observed at similar frequencies to those of East African parasite populations, including the S160N/T mutation in the pfap2mu gene, which has been associated with delayed clearance by artemisinin-based combination therapy. Overall, our work provides a first assessment of P. falciparum genetic diversity within the Lake Victoria basin, a region targeting malaria elimination.


2021 ◽  
Vol 4 ◽  
Author(s):  
Karolina Bacela-Spychalska ◽  
Annette Taugbøl ◽  
Wiesław Babik ◽  
Maciej Pabijan ◽  
David Strand ◽  
...  

Pond ecosystems are hotspots of freshwater biodiversity, often containing many rare and protected species that are not commonly found elsewhere (Harper et al. 2018;Harper et al. 2019). However, even if they constitute c.a. 30% of freshwaters by area, still not enough effort has been put into pond monitoring and management and pond ecosystems are hence relatively poorly understood. Results of ECOPOND project will lead to add valuable knowledge upon pond diversity in geographic gradient taking for consideration human impact by comparing rural and urban areas. The sample design in ECOPOND includes six geographic regions, spanning from the south of Poland to the middle of Norway, where we will sample five replicates of urban and rural ponds in close geographic proximity, making it possible to test the impact of urbanization on biodiversity and biotic homogenization across latitude. We will sample all ponds at spring and late summer, making it possible to assess also seasonality in biodiversity. ECOPOND will utilize environmental DNA and RNA to perform biodiversity screening. The extracted eDNA and eRNA fragments will be amplified with the use of several selected markers for vertebrates, invertebrates, fungi and bacteria. Comparisons between eDNA and eRNA metabarcoding are hypothesized to allow inference between present and past diversity, as eRNA is thought to be only available from live organisms in the community. Moreover, ECOPOND aims at testing the effects of selected invasives species that can have on whole ecosystems. By sampling a range of biotic and abiotic parameters describing studied ponds, we will incorporate the available data for the ponds and employ occupancy modelling methods to assess the habitat preferences of selected invasive alien species. Then we will develop a method that can contribute towards an earlywarning system of evaluating threats to ecosystem status. One of the focus species will be the parasitic fungus Batrachochytrium dendrobatidis (Bd), an infectious fungal pathogen that has caused a number of amphibian declines and extinctions. The European amphibians seem less affected by the parasite at present. However, the fungi could be a direct driver of reduced genetic variation due to selection, or directly reduce the infected amphibian’s overall fitness by reducing the microbiotic diversity on their skin, which in many cases acts as a second immune system. ECOPOND will therefore provide data on genomic variation (using RADseq) for two amphibian species: the smooth newt (Lissotriton vulgaris) and the common toad (Bufo bufo). We will investigate populations of these species inhabiting ponds that are infected and not infected by Bd as well as collect data on their skin microbes (identified using metabarcoding). We will also contrast the genomic diversity between the replicated urban/rural setup and look for repeatable genomic changes. This setup will also be compared for the genomic variation for a potential native prey, the blue-tailed dragonfly, as will ponds with and without fish and/or amphibians (possibly also comparing between native and IAS top-predators) in order to look for predatory selective sweeps in the genome and transcriptome (experimental setup). All ponds will also be analyzed for over 20 water quality parameters and include data on a range of site characteristics that will be used as explanatory variables in all models. ECOPOND will compare large datasets across large geographic regions and will provide detailed knowledge of biodiversity patterns in vertebrates, invertebrates, fungal and microbial species, as well as genomic composition and skin biodiversity for animals inhabiting the same ponds set in an urban context. As a total, ECOPOND will obtain data on the location and status of biodiversity interests, gather data that can help in preventing the establishment of invasive alien species, and eradicating or controlling species that have already become established. And finally, ECOPOND will work closely with stakeholders and develop statistical techniques that can be used for monitoring, detection and protection of biodiversity.


Sign in / Sign up

Export Citation Format

Share Document