15 research outputs found
Close relatives of Mediterranean endemorelict hoverflies (Diptera, Syrphidae) in South Africa : Morphological and molecular evidence in the Merodon melanocerus subgroup
An ongoing study of the genus Merodon Meigen, 1803 in the Republic of South Africa (RSA) has revealed the existence of new species related to M. melanocerus Bezzi, 1915. The M. melanocerus subgroup belongs to the Afrotropical lineage of the M. desuturinus group. Revision of all available material from museums and detailed analyses of newly -collected specimens from our own expeditions to RSA resulted in delimitation of five species: M. capensis Hurkmans sp. n., M. commutabilis Radenkovic et Vujic sp. n., M. drakonis Vujic et Radenkovic sp. n., M. flavocerus Hurkmans sp. n. and M. melanocerus. In addition to classical morphological characters, sequences of the mitochondrial COI gene are provided for four related taxa. Results of molecular phylogenetic analyses supports monophyly of the M. desuturinus group and confirmed delimitation between species. Links between Palaearctic and Afrotropical faunas of this group, as well as possible evolutionary paths, are discussed. Based on phylogenetic analyses, four lineages (putative subgenera) have been recognized within the genus Merodon; besides the three previously established ones, albifrons+desuturinus, aureus (sensu lato) and avidus-nigritarsis, one new lineage named natans is distinguished.Peer reviewe
The Merodon planifacies subgroup (Diptera, Syrphidae) : Congruence of molecular and morphometric evidences reveal new taxa in Drakensberg mountains valleys (Republic of South Africa)
Hoverflies (Syrphidae) represent an insect group of great importance in ecosystems and indicators of ecosystem change. The genus Merodon Meigen, 1803 (tribe Merodontini) is one of the most species-rich hoverfly genera, distributed across the Palaearctic and Afrotropical regions. The genus Merodon Meigen, 1803 is less diverse in the Afrotropical Region than in the Palaearctic (11 versus 160 known species). An ongoing study of the genus Merodon in Africa has revealed the existence of two new species into the taxon previously known as Merodon planifacies Bezzi, 1915. The M. planifacies subgroup belongs to the Afrotropical lineage of the Merodon desuturinus group. Morphological analysis of male genitalia has classified the available specimens of the M. planifacies taxon into two sets: the first one corresponds to M. planifacies with folded theca, while the other with smooth theca, later named Merodon capi complex was found exclusively at the Drakensberg mountains in the Republic of South Africa, specifically in the Cathedral Peak National Park and the Royal Natal National Park. Further, molecular and morphometric evidences revealed two cryptic taxa within this complex: M. capi sp. nov. Vujic et Radenkovic and Merodon roni sp. nov. Radenkovic et Vujic. (c) 2020 Elsevier GmbH. All rights reserved.Peer reviewe
Global commitments to conserving and monitoring genetic diversity are now necessary and feasible
Global conservation policy and action have largely neglected protecting and monitoring genetic diversity—one of the three main pillars of biodiversity. Genetic diversity (diversity within species) underlies species’ adaptation and survival, ecosystem resilience, and societal innovation. The low priority given to genetic diversity has largely been due to knowledge gaps in key areas, including the importance of genetic diversity and the trends in genetic diversity change; the perceived high expense and low availability and the scattered nature of genetic data; and complicated concepts and information that are inaccessible to policymakers. However, numerous recent advances in knowledge, technology, databases, practice, and capacity have now set the stage for better integration of genetic diversity in policy instruments and conservation efforts. We review these developments and explore how they can support improved consideration of genetic diversity in global conservation policy commitments and enable countries to monitor, report on, and take action to maintain or restore genetic diversity
The European Reference Genome Atlas: piloting a decentralised approach to equitable biodiversity genomics.
ABSTRACT: A global genome database of all of Earth’s species diversity could be a treasure trove of scientific discoveries. However, regardless of the major advances in genome sequencing technologies, only a tiny fraction of species have genomic information available. To contribute to a more complete planetary genomic database, scientists and institutions across the world have united under the Earth BioGenome Project (EBP), which plans to sequence and assemble high-quality reference genomes for all ∼1.5 million recognized eukaryotic species through a stepwise phased approach. As the initiative transitions into Phase II, where 150,000 species are to be sequenced in just four years, worldwide participation in the project will be fundamental to success. As the European node of the EBP, the European Reference Genome Atlas (ERGA) seeks to implement a new decentralised, accessible, equitable and inclusive model for producing high-quality reference genomes, which will inform EBP as it scales. To embark on this mission, ERGA launched a Pilot Project to establish a network across Europe to develop and test the first infrastructure of its kind for the coordinated and distributed reference genome production on 98 European eukaryotic species from sample providers across 33 European countries. Here we outline the process and challenges faced during the development of a pilot infrastructure for the production of reference genome resources, and explore the effectiveness of this approach in terms of high-quality reference genome production, considering also equity and inclusion. The outcomes and lessons learned during this pilot provide a solid foundation for ERGA while offering key learnings to other transnational and national genomic resource projects.info:eu-repo/semantics/publishedVersio
Monitoring of species’ genetic diversity in Europe varies greatly and overlooks potential climate change impacts
Genetic monitoring of populations currently attracts interest in the context of the Convention on Biological Diversity but needs long-term planning and investments. However, genetic diversity has been largely neglected in biodiversity monitoring, and when addressed, it is treated separately, detached from other conservation issues, such as habitat alteration due to climate change. We report an accounting of efforts to monitor population genetic diversity in Europe (genetic monitoring effort, GME), the evaluation of which can help guide future capacity building and collaboration towards areas most in need of expanded monitoring. Overlaying GME with areas where the ranges of selected species of conservation interest approach current and future climate niche limits helps identify whether GME coincides with anticipated climate change effects on biodiversity. Our analysis suggests that country area, financial resources and conservation policy influence GME, high values of which only partially match species’ joint patterns of limits to suitable climatic conditions. Populations at trailing climatic niche margins probably hold genetic diversity that is important for adaptation to changing climate. Our results illuminate the need in Europe for expanded investment in genetic monitoring across climate gradients occupied by focal species, a need arguably greatest in southeastern European countries. This need could be met in part by expanding the European Union’s Birds and Habitats Directives to fully address the conservation and monitoring of genetic diversity
Positive selection and precipitation effects on the mitochondrial NADH dehydrogenase subunit 6 gene in brown hares (Lepus europaeus) under a phylogeographic perspective
Gedeon, Csongor Istvan/0000-0003-4027-2409; Stefanovic, Milomir/0000-0001-6294-3782WOS: 000513587800001PubMed: 31703111Previous studies in hares and jackrabbits have indicated that positive selection has shaped the genetic diversity of mitochondrial genes involved in oxidative phosphorylation, which may affect cellular energy production and cause regional adaptation to different environmental (climatic) pressures. In the present study, we sequenced the NADH dehydrogenase subunit 6 (MT-ND6) gene of 267 brown hares (L. europaeus) from Europe and Asia Minor and tested for positive selection and adaptations acting on amino acid sequences (protein variants). Molecular diversity indices and spatial clustering were assessed by DnaSP, Network, and Geneland, while the presence of selection signals was tested by codeml in PAML, and by using the Datamonkey Adaptive Evolution web server. The SPSS software was used to run multinomial regression models to test for possible effects of climate parameters on the currently obtained protein variants. Fifty-eight haplotypes were revealed with a haplotype diversity of 0.817, coding for 17 different protein variants. The MT-ND6 phylogeographic pattern as determined by the nucleotide sequences followed the earlier found model based on the neutrally evolving D-loop sequences, and reflected the earlier found phylogeographic Late Pleistocene scenario. Based on several selection tests, only one codon position consistently proved to be under positive selection. It did occur exclusively in the evolutionarily younger hares from Europe and it gave rise to several protein variants from the southeastern and south-central Balkans. The occurrence of several of those variants was significantly favored under certain precipitation conditions, as proved by our multinomial regression models. Possibly, the great altitudinal variation in the Balkans may have lead to bigger changes in precipitation across that region and this may have imposed an evolutionarily novel selective pressure on the protein variants and could have led to regional adaptation.Ministry of Education, Science and Technological Development, Republic of Serbia [43002]; Provincial Secretariat for Science and Technological Development [0601 78/37-316]; Wildlife Research - Franz Suchentrunk [1/2017]This work was financially supported by the Ministry of Education, Science and Technological Development, Republic of Serbia Grant No. 43002, project title "Biosensing technology and global system for long-term research and integrated management of ecosystems"; and the Provincial Secretariat for Science and Technological Development Grant No. 0601 78/37-316, project title "Evaluation of ecological networks in AP Vojvodina as support for nature conservation". Partial financial support was provided by Wildlife Research - Franz Suchentrunk (project No. 1/2017). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Purifying selection shaping the evolution of the Toll-like receptor 2 TIR domain in brown hares (Lepus europaeus) from Europe and the Middle East
Gedeon, Csongor Istvan/0000-0003-4027-2409WOS: 000522708700002PubMed: 32236892Toll-like receptors (TLRs) are transmembrane proteins of the innate immune system, composed of the ectodomain involved in pathogen recognition and the intracellular Toll/interleukin-1 receptor (TIR) domain important for downstream signal transduction. Here, we analyze the genetic variability of TIR nucleotide and amino-acid sequences of the TLR2 gene in 243 brown hares from Europe and the Middle East and tested for the presence of selection signals and spatial structuring. TLR2 TIR domain sequences were PCR amplified and sequenced, while genotyping was performed by phasing. Genetic diversity indices were calculated in DnaSP and Arlequin, while presence of selection signals was tested using MEGA and the Datamonkey web server. The presence of spatial patterns in TIR sequence distribution was tested by spatial Principal Component Analysis (sPCA) in adegenet. A total of 13 haplotypes were revealed with haplotype diversity of 0.424, and nucleotide diversity (pi) of 0.00138. Two spatial clusters were revealed: "Anatolia/Middle East" and "Europe". In Anatolia the two most prevalent amino-acid variants, A and B (the latter being the most ancestral) were maintained at similar frequencies; but in Europe a shift in genotype frequencies was observed as well as a higher number of nonsynonymous substitutions giving rise to novel amino-acid protein variants originating from the evolutionarily younger protein variant. Molecular diversity (haplotype and nucleotide diversity) indices were significantly higher in the "Anatolia/Middle East" cluster. A signal of purifying selection was detected acting on the TIR sequences.[1/2018]We thank all local hunters, Prof. Philip U. Alkon, PhD (Israel), Orsolya Vincze, PhD (Romania) and Sim Broekhuizen, PhD (The Netherlands) for helping collecting the samples. Partial financial support for this work was provided by Wildlife Research-Franz Suchentrunk (Project No. 1/2018)
From north to south and back: the role of the Balkans and other southern peninsulas in the recolonization of Europe by wild boar
Aim We analysed mitochondrial DNA (mtDNA) variation in wild boar (Sus
scrofa) in the Balkans, including individuals from the northern Dinaric Balkans,
an area that had not previously been characterized. Our aims were: (1) to
reveal the level of genetic diversity and structuring and examine the demographic
expansion of wild boar populations in the Balkans and Europe; (2) to
examine the role of the Balkan gene pool in the post-LGM (Last Glacial Maximum)
recolonization of Europe; and (3) to elucidate the phylogenetic position
of European and Balkan wild boar in a Eurasian context by comparing
sequences of wild boar worldwide.
Location Balkan Peninsula.
Methods A fragment of the mtDNA control region (443 bp) was sequenced
in 163 wild boar from the Balkans. Phylogenetic analyses, using MrBayes and
network, were carried out together with 188 previously published sequences
from the Balkan Peninsula. Phylogenetic analyses were also performed with an
additional 876 wild boar sequences from around the world.
Results Sixteen haplotypes were found in the new samples, including 11 not
previously reported in the Balkans. Phylogenetic analyses based on all known
Balkan haplotypes indicated the existence of population structuring, revealing
two groups: Continental Balkans and South Balkans. The analysis of the complete
dataset, comprising 1227 mtDNA sequences from wild boar sampled
worldwide, revealed the presence of 168 different haplotypes. All Balkan haplotypes
fell into the E1 haplogroup, except one sample that possessed an Asian
haplotype. Within the E1 haplogroup, 50% of the haplotypes were unique to
the Balkan Peninsula.
Main conclusions Wild boar from the Balkans exhibited high genetic diversity.
Similar phylogeographical patterns emerge in all southern European peninsulas,
arising from post-LGM expansion, and all three peninsulas played a
similar role in the post-glacial recolonization of Europe by wild boar. This supports
a leading-edge colonization hypothesis for all three peninsulas