Search results for "vicariance"
showing 10 items of 40 documents
Genetic structure in the Mediterranean seagrass Posidonia oceanica: disentangling past vicariance events from contemporary patterns of gene flow
2010
The Mediterranean Sea is a two-basin system, with the boundary zone restricted to the Strait of Sicily and the narrow Strait of Messina. Two main population groups are recognized in the Mediterranean endemic seagrass Posidonia oceanica, corresponding to the Western and the Eastern basins. To address the nature of the East-West cleavage in P. oceanica, the main aims of this study were: (i) to define the genetic structure within the potential contact zone (i.e. the Strait of Sicily) and clarify the extent of gene flow between the two population groups, and (ii) to investigate the role of present water circulation patterns vs. past evolutionary events on the observed genetic pattern. To achiev…
A mitochondrial phylogeography of Brachidontes variabilis (Bivalvia: Mytilidae) reveals three cryptic species
2007
This study examined genetic variation across the range of Brachidontes variabilis to produce a molecular phylogeography. Neighbour joining (NJ), minimum evolution (ME) and maximum parsimony (MP) trees based on partial mitochondrial DNA sequences of 16S-rDNA and cytochrome oxidase (COI) genes revealed three monophyletic clades: (1) Brachidontes pharaonis s.l. from the Mediterranean Sea and the Red Sea; (2) B. variabilis from the Indian Ocean; (3) B. variabilis from the western Pacific Ocean. Although the three clades have never been differentiated by malacologists employing conventional morphological keys, they should be ascribed to the taxonomic rank of species. The nucleotide divergences b…
Complete phylogeny and historical biogeography of true rosefinches (Aves:Carpodacus)
2013
True rosefinches (Aves: Carpodacus) are restricted to Eurasia, and 19 out of 25 species occur in the Sino-Himalayas, making this the likely centre of origin. To test this hypothesis, suggested species splits had to be evaluated and potential further cryptic diversity unravelled. A taxon-complete dated molecular phylogeny was reconstructed using maximum-likelihood and Bayesian methods. Maximum-parsimony and likelihood approaches were applied to deduce ancestral areas. Rosefinches, including the widespread Carpodacus erythrinus (Pallas, 1770), originated in south-west China (and the Himalayas) 14 Mya, and gave rise to a smaller clade consisting of C. erythrinus, Haematospiza sipahi (Hodgson, …
Phylogenetic and biogeographical inferences for Pancratium (Amaryllidaceae), with an emphasis on the Mediterranean species based on plastid sequence …
2012
The phylogenetics and biogeography of Pancratium (Amaryllidaceae) were investigated, with a focus on the Mediterranean and adjacent areas, with the aim of contributing new information towards a better understanding of the evolutionary history of the genus and the taxonomic placement of P. linosae and P. hirtum. To address these questions, we sequenced four plastid DNA markers: the ndhF and rbcL genes, the trnL(UAA)-trnF(GAA) intergenic spacer and the trnL(UAA) intron, analysing them using parsimony, likelihood and Bayesian approaches. The results show that the relationships among the majority of the species are resolved; however, the relationships of one of the major clades of the genus are…
Dispersal history of a spider (Stegodyphus lineatus) across contiguous deserts: vicariance and range expansion
2005
Israel marks a crossroads between three continents encompassing several phytogeographical and zoogeographical zones. In this complex area, the flow of species from different biogeographical regions creates opportunities to study how geographical division and colonization routes affect current distribution and structure of resident populations of organisms associated with desert and arid environments, habitats that may have persisted throughout Pleistocene glacial periods. The present paper analyses the population history of the spider Stegodyphus lineatus in the contiguous Negev and Judean deserts in Israel using allozyme and mtDNA variation. The distinct patterns of variation indicate that…
Glacial survival and post-glacial recolonization of an arctic-alpine freshwater insect (Arcynopteryx dichroa, Plecoptera, Perlodidae) in Europe
2012
Aim General models for understanding the climate-driven processes of post-glacial colonization in European arctic–alpine species are mainly derived from studies on temperate terrestrial taxa. However, cold-adapted freshwater species may tolerate or even thrive under colder climatic conditions as flowing water habitats are thermally buffered against freezing and extremely cold temperatures. Here, we investigate the European Pleistocene and Holocene history of the arctic–alpine stonefly Arcynopteryx dichroa. Location Europe. Methods We used two genetic data sets (mitochondrial sequence data and nuclear microsatellite data) to investigate the glacial survival and post-glacial recolonization ro…
Parapatric diversification after post-glacial range expansion in the gall flyUrophora cardui(Tephritidae)
2010
Aim Primary and secondary genetic clines in post-glacial colonized regions have different implications for biogeographic distributions and the origin of species. Primary clines arise in situ after colonization as adaptive responses to environmental gradients, while secondary clines are caused by contact between vicariant lineages. Here we analyse primary versus secondary origin of a genetic cline in the tephritid fly Urophora cardui in Jutland, Denmark, in a post-glacial landscape. Location Western Palaearctic. Methods Phylogeographic and demographic analyses of U. cardui based on mitochondrial DNA (mtDNA) genealogies, hierarchical genetic variance tests based on allozymes and distributi…
The phylogeny and biogeography of Gentiana L. sect. Ciminalis (Adans.) Dumort.: A historical interpretation of distribution ranges in the European hi…
1998
Abstract Gentiana sect. Ciminalis consists of seven mostly ecologically or geographically vicariant and closely related species which are distributed throughout the South and Central European high mountains. The analysis of a RAPD data set and trn L-intron and ITS sequences resulted in slightly different phylogenetic hypotheses. In the preferred hypothesis the group consists of two completely resolved main lineages: 1) G. clusii and G. alpina. 2) G. dinarica, G. acaulis, G. ligustica, G. angustifolia and G. occidentalis. The most important conclusions we have drawn from this phylogenetic hypothesis and from the observed patterns of molecular variation are: 1) The calcifuge ecology of G. aca…
2015
The Indonesian island of Sulawesi harbors a highly endemic and diverse fauna sparking fascination since long before Wallace’s contemplation of biogeographical patterns in the region. Allopatric diversification driven by geological or climatic processes has been identified as the main mechanism shaping present faunal distribution on the island. There is both consensus and conflict among range patterns of terrestrial species pointing to the different effects of vicariant events on once co-distributed taxa. Tarsiers, small nocturnal primates with possible evidence of an Eocene fossil record on the Asian mainland, are at present exclusively found in insular Southeast Asia. Sulawesi is hotspot o…
New perspectives on the evolution of the genus Typhlatya (Crustacea, Decapoda): first record of a cavernicolous atyid in the Iberian Peninsula, Typhl…
1995
On several occasions, shrimps belonging to a new species of the genus Typhlatya were collected in a cave in the province of Castellón, Spain. This is the first record of the genus in the Iberian Peninsula. The species is described and the validity, distribution, and zoogeography of the genus, as well as the status of the genus Spelaeocaris, are discussed. Former models for the evolution of the genus Typhlatya and its genus group are reviewed, as well as the system of inner classification of the Atyidae and its biogeographical meaning. For the age and evolution of the genus we developed a new model based on vicariance principles that involves further evolution of each species after the disru…