Browsing by Subject "PHYLOGEOGRAPHY"

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  • Acanski, Jelena; Vujic, Ante; Djan, Mihajla; Obreht Vidakovic, Dragana; Ståhls, Gunilla; Radenkovic, Snezana (2016)
    Several recent studies have detected and described complexes of cryptic and sibling species in the genus Merodon (Diptera, Syrphidae). One representative of these complexes is the Merodon avidus complex that contains four sibling species, which have proven difficult to distinguish using traditional morphological characters. In the present study, we use two geometric morphometric approaches, as well as molecular characters of the 5' -end of the mtDNA COI gene, to delimit sibling taxa. Analyses based on these data were used to strengthen species boundaries within the complex, and to validate the status of a previously-recognized cryptic taxon from Lesvos Island (Greece), here described as Merodon megavidus Vujic & Radenkovic sp. nov. Geometric morphometric results of both wing and surstylus shape confirm the present classification for three sibling species-M. avidus (Rossi, 1790), M. moenium Wiedemann in Meigen, 1822 and M. ibericus Vujic, 2015-and, importantly, clearly discriminate the newly-described taxon Merodon megavidus sp. nov. In addition to our geometric morphometric results, supporting characters were obtained from molecular analyses of mtDNA COI sequences, which clearly differentiated M. megavidus sp. nov. from the other members of the M. avidus complex. Molecular analyses revealed that the earliest divergence of M. ibericus occurred around 800 ky BP, while the most recent separation happened between M. avidus and M. moenium around 87 ky BP.
  • Schultz, Eduardo D.; Pérez-Emán, Jorge; Aleixo, Alexandre; Miyaki, Cristina Y.; Brumfield, Robb T.; Cracraft, Joel; Ribas, Camila C. (2019)
    Dendrocincla woodcreepers are ant-following birds widespread throughout tropical America. Species in the genus are widely distributed and show little phenotypic variation. Notwithstanding, several subspecies have been described, but the validity of some of these taxa and the boundaries among them have been discussed for decades. Recent genetic evidence based on limited sampling has pointed to the paraphyly of D. fuliginosa, showing that its subspecies constitute a complex that also includes D. anabatina and D. turdina. In this study we sequenced nuclear and mitochondrial markers for over two hundred individuals belonging to the D. fuliginosa complex to recover phylogenetic relationships, describe intraspecific genetic diversity and provide historical biogeographic scenarios of diversification. Our results corroborate the paraphyly of D. fuliginosa, with D. turdina and D. anabatina nested within its recognized subspecies. Recovered genetic lineages roughly match the distributions of described subspecies and congruence among phylogenetic structure, phenotypic diagnosis and distribution limits were used to discuss current systematics and taxonomy within the complex, with special attention to Northern South America. Our data suggest the origin of the complex in western Amazonia, associated with the establishment of upland forests in the area during the early Pliocene. Paleoclimatic cycles and river rearrangements during the Pleistocene could have, at different times, both facilitated dispersal across large Amazonian rivers and the Andes and isolated populations, likely playing an important role in differentiation of extant species. Previously described hybridization in the headwaters of the Tapajós river represents a secondary contact of non-sister lineages that cannot be used to test the role of the river as primary source of diversification. Based on comparisons of D. fuliginosa with closely related understory upland forest taxa, we suggest that differential habitat use could influence diversification processes in a historically changing landscape, and should be considered for proposing general mechanisms of diversification.
  • Ribas, Camila C.; Aleixo, Alexandre (2019)
    Amazonia has been a focus of interest since the early days of biogeography as an intrinsically complex and extremely diverse region. This region comprises an intricate mosaic that includes diverse types of forest formations, flooded environments and open vegetation. Increased knowledge about the distribution of species in Amazonia has led to the recognition of complex biogeographic patterns. The confrontation of these biogeographic patterns with information on the geological and climatic history of the region has generated several hypotheses dedicated to explain the origin of the biological diversity. Genomic information, coupled with knowledge of Earth's history, especially the evolution of the Amazonian landscape. presents fascinating possibilities for understanding the mechanisms that govern the origin and maintenance of diversity patterns in one of the most diverse regions of the world. For this we will increasingly need more intense and coordinated interactions between researchers studying biotic diversification and the evolution of landscapes. From the interaction between these two fields of knowledge that are in full development, an increasingly detailed understanding of the historical mechanisms related to the origin of the species will surely arise.
  • Ling, Jiaxin; Smura, Teemu; Tamarit, Daniel; Huitu, Otso; Voutilainen, Liina; Henttonen, Heikki; Vaheri, Antti; Vapalahti, Olli; Sironen, Tarja (2018)
    Hantaviruses have co-existed with their hosts for millions of years. Seewis virus (SWSV), a soricomorph-borne hantavirus, is widespread in Eurasia, ranging from Central Siberia to Western Europe. To gain insight into the phylogeography and evolutionary history of SWSV in Finland, lung tissue samples of 225 common shrews (Sorex araneus) trapped from different parts of Finland were screened for the presence of SWSV RNA. Forty-two of the samples were positive. Partial small (S), medium (M) and large (L) segments of the virus were sequenced, and analyzed together with all SWSV sequences available in Genbank. The phylogenetic analysis of the partial S-segment sequences suggested that all Finnish SWSV strains shared their most recent common ancestor with the Eastern European strains, while the L-segment suggested multiple introductions. The difference between the Land S-segment phylogenies implied that reassortment events play a role in the evolution of SWSV. Of the Finnish strains, variants from Eastern Finland occupied the root position in the phylogeny, and had the highest genetic diversity, supporting the hypothesis that SWSV reached Finland first form the east. During the spread in Finland, the virus has formed three separate lineages, identified here by correlation analysis of genetic versus geographic distance combined with median-joining network analysis. These results support the hypothesis that Finnish SWSV recolonized Finland with its host, the common shrew, from east after the last ice age 12,000-8000 years ago, and then subsequently spread along emerging land bridges towards west or north with the migration and population expansion of its host.
  • Moura, Carina Carneiro de Melo; Fernandes, Alexandre M.; Aleixo, Alexandre; Pereira de Araujo, Helder Farias; Mariano, Erich de Freitas; Wink, Michael (2020)
    We focus on reconstructing a spatiotemporal scenario of diversification of a widespread South American species, the Pectoral Sparrow Arremon taciturnus (Aves: Passerellidae). This species is widely distributed in both the humid and the dry forests of South America and therefore provides an interesting model for understanding the connection between different biomes of South America. We examined nucleotide sequences of the mitochondrial genes Cytochrome b (cyt-b) and NADH subunit 2 (ND2) from 107 specimens, and one nuclear marker (intron 7 of the beta-fibrinogen gene) from a subset of samples collected across the distribution ranges of A. t. taciturnus and A. t. nigrirostris. Six major lineages were recovered in the phylogenies that displayed high levels of variance of allele frequencies and corresponded to distinct geographical locations. The estimation of divergence times provided evidence that diversification of the six lineages of the Pectoral Sparrow occurred throughout the Late Pleistocene across major cis-Andean biomes and Amazonian interfluves. Our dataset for A. taciturnus provides further evidence that rivers in Amazonia constitute barriers promoting allopatric speciation, with occasional sharing of alleles among lineages, particularly those with adjacent distributions.
  • Vasilyeva, Yulia; Chertov, Nikita; Nechaeva, Yulia; Sboeva, Yana; Pystogova, Nina; Boronnikova, Svetlana; Kalendar, Ruslan (2021)
    In order to carry out activities aimed at conservation and rational use of forest resources; it is necessary to study the main forest-forming plant species in detail. Scots pine (Pinus sylvestris L., Pinaceae) is mainly found in the boreal forests of Eurasia and is not so often encountered in the east of the East European Plain. The aim of the study was to study the genetic diversity, structure and differentiation of Scots pine populations in the east of the East European Plain. We studied ten populations of P. sylvestris using the Inter Simple Sequence Repeats (ISSR)-based DNA polymorphism detection method. Natural populations are demonstrated by relatively high rates of genetic diversity (He = 0.167; ne = 1.279; I = 0.253). At the same time, there is a tendency for a decrease in the genetic diversity of the studied populations of P. sylvestris from west to east. Analysis of the genetic structure shows that the studied populations are highly differentiated (GST = 0.439), the intrapopulation component accounts for about 56% of the genetic diversity. Using various algorithms for determining the spatial genetic structure, it is found that the studied populations form two groups of populations in accordance with geographic location. With the help of a genetic originality coefficient, populations with specific and typical gene pools are identified. They are recommended as sources of genetic diversity and reserves for the conservation of genetic resources of the species
  • Reis, Camila Alves; Dias, Cleyssian; Araripe, Juliana; Aleixo, Alexandre; Anciaes, Marina; Sampaio, Iracilda; Schneider, Horacio; do Rego, Pericles Sena (2020)
    We used molecular tools and a multilocus approach to investigate the phylogeography of Lepidothrix coronata across most of its ample range. We sequenced six DNA fragments to produce phylogenies, molecular dating estimates, analyses of the dynamics of the demographic history of the species and a biogeographic analysis to estimate the events and changes in the ancestral distribution of the species. The results indicated the presence of four well-established lineages, with high levels of divergence. These lineages are delineated by well-defined geographic barriers, with one lineage, restricted to the west of the Andes, being the first to diverge from the complex. The other three lineages are exclusive to the Amazonian distribution of the species, with two being found north of the Amazon River, and the third, south of the Amazon. Some of the relationships found between these lineages were distinct from those described in previous studies. Important disagreements were found between the mtDNA phylogeny and that of the multilocus analysis, in relation to the lineages located to the west of the Andes. We propose that past introgression events may have influenced shifts in the relationships between lineages, despite the fact that the groups were well defined in both the phylogenies. The biogeographic analysis indicates that the lineages arose through successive vicariance events, which had a primary role in the diversification of the group. Two or three genetically structured subclades were also found within each Amazonian lineage, although these subclades are not isolated by an obvious geographic barrier.
  • Batini, Chiara; Hallast, Pille; Vagene, Ashild J.; Zadik, Daniel; Eriksen, Heidi A.; Pamjav, Horolma; Sajantila, Antti; Wetton, Jon H.; Jobling, Mark A. (2017)
    Interpretations of genetic data concerning the prehistory of Europe have long been a subject of great debate, but increasing amounts of ancient and modern DNA data are now providing new and more informative evidence. Y-chromosome resequencing studies in Europe have highlighted the prevalence of recent expansions of male lineages, and focused interest on the Bronze Age as a period of cultural and demographic change. These findings contrast with phylogeographic studies based on mitochondrial DNA (mtDNA), which have been interpreted as supporting expansions from glacial refugia. Here we have undertaken a population-based resequencing of complete mitochondrial genomes in Europe and the Middle East, in 340 samples from 17 populations for which Y-chromosome sequence data are also available. Demographic reconstructions show no signal of Bronze Age expansion, but evidence of Paleolithic expansions in all populations except the Saami, and with an absence of detectable geographical pattern. In agreement with previous inference from modern and ancient DNA data, the unbiased comparison between the mtDNA and Y-chromosome population datasets emphasizes the sex-biased nature of recent demographic transitions in Europe.
  • Natri, Heini M.; Merilä, Juha; Shikano, Takahito (2019)
    Sex determination is a fundamentally important and highly diversified biological process, yet the mechanisms behind the origin of this diversity are mostly unknown. Here we suggest that the evolution of sex determination systems can be driven by a chromosomal inversion. We show that an XY system evolved recently in particular nine-spined stickleback (Pungitius pungitius) populations, which arose from ancient hybridization between two divergent lineages. Our phylogenetic and genetic mapping analyses indicate that the XY system is formed in a large inversion that is associated with hybrid sterility between the divergent lineages. We suggest that a new male-determining gene evolved in the inversion in response to selection against impaired male fertility in a hybridized population. Given that inversions are often associated with hybrid incompatibility in animals and plants, they might frequently contribute to the diversification of sex determination systems.
  • Wei, Shichao; Li, Zitong; Momigliano, Paolo; Fu, Chao; Wu, Hua; Merilä, Juha (2020)
    The role of geological events and Pleistocene climatic fluctuations as drivers of current patterns of genetic variation in extant species has been a topic of continued interest among evolutionary biologists. Nevertheless, comprehensive studies of widely distributed species are still rare, especially from Asia. Using geographically extensive sampling of many individuals and a large number of nuclear single nucleotide polymorphisms (SNPs), we studied the phylogeography and historical demography ofHyla annectanspopulations in southern China. Thirty-five sampled populations were grouped into seven clearly defined genetic clusters that closely match phenotype-based subspecies classification. These lineages diverged 2.32-5.23 million years ago (Ma), a timing that closely aligns with the rapid and drastic uplifting of the Qinghai-Tibet Plateau and adjacent southwest China. Demographic analyses and species distribution models indicate that different populations of this species have responded differently to past climatic changes. In the Hengduan Mountains, most populations experienced a bottleneck, whereas the populations located outside of the Hengduan Mountains have gradually declined in size since the end of the last glaciation. In addition, the levels of phenotypic and genetic divergence were strongly correlated across major clades. These results highlight the combined effects of geological events and past climatic fluctuations, as well as natural selection, as drivers of contemporary patterns of genetic and phenotypic variation in a widely distributed anuran in Asia.
  • Vanderpoorten, Alain; Patino, Jairo; Desamore, Aurelie; Laenen, Benjamin; Gorski, Piotr; Papp, Beata; Hola, Eva; Korpelainen, Helena; Hardy, Olivier (2019)
    1. Bryophytes are typically seen as extremely efficient dispersers. Experimental evidence suggests that efficient short-distance dispersal coupled with random long-distance dispersal (LDD) leads to an inverse isolation effect. Under the latter, a higher genetic diversity of colonizing propagules is expected with increasing isolation, counteracting differentiation beyond the range of short-distance dispersal. 2. This expectation is tested from a review of evidence on spatial genetic structure and analyses of isolation-by-distance (IBD) at different scales. 3. A decay of the IBD signal, characterized by non-significant slopes between kinship coefficients and geographic distance was observed beyond 100 m. A second slope shift was observed at distances larger than 1 km, with a proportion of significant slopes in more than one third of the datasets. 4. The decay of the IBD signal beyond 100 m, which reflects efficient LDD, is consistent with the inverse isolation hypothesis. Persistence of a significant IBD signal at medium ranges in one third of the analysed cases suggests, however, that the inverse isolation effect is not a rule in bryophyte spore dispersal. Furthermore, the higher proportion of significant IBD patterns observed at scales over 100 km likely marks the limits of regional dispersal, beyond which an increasingly smaller proportion of spores travel. 5. Synthesis. We discuss the differences between experimental and genetic estimates of spore dispersal and conclude that geographic distance remains a significant proxy of spore colonization rates, with major consequences for our understanding of actual migration capacities in bryophytes, and hence, our capacity to model range shifts in a changing world.