Search results for "Biological dispersal"
showing 10 items of 326 documents
The Population Genomics of Anopheles gambiae Species Complex: Progress and Prospects
2021
Anopheles gambiae sensu lato is a species complex containing principal malaria vectors such as An. gambiae sensu stricto, An. coluzzii, and An. arabiensis. Numerous studies have shown dynamic species hybridization among member of this complex makes them an ideal model for studying evolution and speciation as well as for applied vector biology. Applying a population genomics approach to the An. gambiae and An. coluzzii species group has led to a number of important and epidemiologically relevant insights including: (1) organization of genomic divergence into “islands of speciation”; (2) competing models of population origin of An. gambiae and An. Coluzzii; (3) description of asymmetric intro…
Ecomorphological predictors of natal dispersal distances in birds.
2008
1. Dispersal is one of the key ecological parameters but it is very difficult to quantify directly. As a consequence, empirical studies often ignore dispersal or use indirect measures. 2. Ringing data have previously been used to estimate the natal dispersal distances of 47 British passerine bird species. This provides an excellent opportunity to examine the potential of various indirect measures to predict natal dispersal distances in British birds. 3. We use a phylogenetic comparative framework and single- and multipredictor models including ecomorphological, behavioural or ecological traits to predict natal dispersal distance. 4. A multipredictor model that includes Kipp's distance (a me…
Population structure and incidence of the stolbur phytoplasma vectorHyalesthes obsoletus(Cixiidae) among geographic regions in Switzerland
2013
The dissemination of stolbur phytoplasma (16Sr-XIIA group)-induced yellows diseases depends on the dispersal biology and host plant fidelity of the planthopper vector Hyalesthes obsoletus (Hemiptera: Cixiidae). We analysed the degree of these two properties in H. obsoletus by studying its population genetic structure and stolbur infection rates relative to the two major host plants, Convolvolus arvensis and Urtica dioica, in order to infer relevant divisions for stolbur epidemiology in Swiss viticultural regions. Three regional populations with the potential to determine stolbur epidemiology in distinct ways were identified. First, populations associated with U. dioica in northern Switzerla…
Do not disturb the family: roles of colony size and human disturbance in the genetic structure of lesser kestrel
2015
Dispersal and philopatry are fundamental processes influencing the genetic structure and persistence of populations, and might be affected by isolation and habitat perturbation. Habitat degradation induced by human activities could have detrimental consequences on the genetic structure of populations. Therefore, it is crucial to understand the role of human impact in promoting or disrupting the genetic structure. Here, we conducted a genetic analysis using 12 polymorphic microsatellite markers of 70 lesser kestrels Falco naumanni from 10 breeding colonies of two subpopulations in Sicily (southern Italy). Genetic differentiation between the two subpopulations was negligible, and linear dista…
Comparative population genetic structures of the fruit flyUrophora carduiand its primary parasitoidEurytoma robusta
2003
The interaction between two species may depend on geographic scale and this in turn can affect co-evolution among them. The present study comparatively examines population genetic structures of the tephritid gall fly Urophora cardui and its primary ectoparasitoid Eurytoma robusta for inference of relative dispersal patterns and host parasitoid specificity. Genetic differentiation patterns indicated two levels of hierarchical structure in both species: locally similar distance-dependencies but globally differences. Locally, both species showed isolation by distance and a high correlation between host anti parasitoid F ST for the same population-pairs was found. At the local level, E. robusta…
Evolutionary processes in a continental island system: molecular phylogeography of the Aegean Nigella arvensis alliance (Ranunculaceae) inferred from…
2005
Continental shelf island systems, created by rising sea levels, provide a premier setting for studying the effects of past fragmentation, dispersal, and genetic drift on taxon diversification. We used phylogeographical (nested clade) and population genetic analyses to elucidate the relative roles of these processes in the evolutionary history of the Aegean Nigella arvensis alliance (= ‘coenospecies’). We surveyed chloroplast DNA (cpDNA) variation in 455 individuals from 47 populations (nine taxa) of the alliance throughout its core range in the Aegean Archipelago and surrounding mainland areas of Greece and Turkey. The study revealed the presence of three major lineages, with largely nonove…
Modelling drift of pelagic offspring: the importance of egg surveys in providing a realistic model initialization
2015
Abstract Having valid information about the location and dynamics of biological processes is important for coastal management. In this context modelling, the pelagic drift of early life stages has been shown to be an important tool for understanding the spatial scale of population dynamics in marine systems. Often simulated particles are released in hypothetical quantities at assumed spawning grounds with no or few field data to guide the model parametrization. In this study, we combine high-resolution field data and state-of-the-art oceanographic modelling and use a probabilistic approach to construct kernel density distributions of the dispersal of pelagic fish eggs. Specifically, the pot…
Origination and extinction patterns of mammals in three central Western Mediterranean islands from the Late Miocene to Quaternary
2008
Abstract An overview of the population histories of three insular realms (Gargano palaeo-archipelago, Sardinia–Maritime Tuscany palaeo-bioprovince and the Sicilian insular complex) during the Late Miocene and Quaternary are here presented. The complexity of biodiversity changes in the islands is analysed to propose an interpretation of origination and extinction patterns. The study highlighted several important aspects of insular faunas. Evolutionary radiations were found to contribute significantly only to the Gargano faunal diversity, likely because the area was an archipelago at the time. Another interesting result is that large and small mammals do not disperse and become extinct all at…
A review of methods to assess connectivity and dispersal between fish populations in the Mediterranean Sea
2013
Fish populations are linked to each other via dispersal of individuals as eggs, larvae, juveniles or adults. The understanding of this process, known as connectivity, has a pivotal role for the management of overexploited fish stocks and the development of accurate conservation strategies. Knowledge on connectivity and fish movements is considered fundamental toward the correct design of marine protected area (MPA) networks for the achievement of the benefits of protection. Connectivity patterns are still largely unknown worldwide. A general lack of knowledge is particularly evident for the Mediterranean Sea where few studies dealing with this topic have been carried out and some methods, c…
Temporal genetic structure in a poecilogonous polychaete: the interplay of developmental mode and environmental stochasticity
2014
Background: Temporal variation in the genetic structure of populations can be caused by multiple factors, including natural selection, stochastic environmental variation, migration, or genetic drift. In benthic marine species, the developmental mode of larvae may indicate a possibility for temporal genetic variation: species with dispersive planktonic larvae are expected to be more likely to show temporal genetic variation than species with benthic or brooded non-dispersive larvae, due to differences in larval mortality and dispersal ability. We examined temporal genetic structure in populations of Pygospio elegans, a poecilogonous polychaete with within-species variation in developmental m…