Influence of evolutionary forces and demographic processes on the genetic structure of three Croatian populations: A maternal perspective

Abstract We analysed the genetic divergence and morphology of the aedeagus (i.e. phallobase and parameres) in Canthon cyanellus at different geographical levels. The results from both approaches were compared with the current taxonomic assignment of the C. cyanellus complex, which includes three subspecies. We found a high variation in all the morphological characters of the aedeagus in the populations analysed; the morphometric variation was not geographically structured, either by population or by region. The genealogical analysis indicates a significant genetic structure that does not match either the morphological variation in the male genitalia or the previous subspecific taxonomic classification. Our results suggest that the morphological variation of the aedeagus is seemingly not an isolating reproductive barrier and that the intra- and interpopulation morphological variability of the aedeagus in the C. cyanellus complex does not permit the division into several species. We suggest that other evolutionary forces, such as genetic drift and sexual selection, have influenced the evolution of the male genitalia and the incipient differentiation of this species complex.

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Genetic Structure of Cronartium ribicola Populations in Eastern Canada

Phytopathology ◽

10.1094/phyto.1999.89.10.915 ◽

1999 ◽

Vol 89 (10) ◽

pp. 915-919 ◽

Cited By ~ 26

Author(s):

K. Et-touil ◽

L. Bernier ◽

J. Beaulieu ◽

J. A. Bérubé ◽

A. Hopkin ◽

...

Keyword(s):

Genetic Structure ◽

Genetic Differentiation ◽

Distribution Systems ◽

Gene Diversity ◽

Isolation By Distance ◽

Random Amplified Polymorphic Dna ◽

Cronartium Ribicola ◽

Eastern Canada ◽

Long Distance ◽

Evolutionary Forces

The genetic structure of populations of Cronartium ribicola was studied by sampling nine populations from five provinces in eastern Canada and generating DNA profiles using nine random amplified polymorphic DNA markers. Most of the total gene diversity (Ht = 0.386) was present within populations (Hw = 0.370), resulting in a low level of genetic differentiation among populations in northeastern North America (Fst = 0.062). A hierarchical analysis of genetic structure using an analysis of molecular variance (AMOVA) revealed no statistically significant genetic differentiation among provinces or among regions. Yet, genetic differentiation among populations within regions or provinces was small (AMOVA φst = 0.078) but statistically significant (P < 0.001) and was several orders of magnitude larger than differentiation among provinces. This is consistent with a scenario of subpopulations within a metapopulation, in which random drift following migration and new colonization are major evolutionary forces. A phenetic analysis using genetic distances revealed no apparent correlation between genetic distance and the province of origin of the populations. The hypothesis of isolation-by-distance in the eastern populations of C. ribicola was rejected by computing Mantel correlation coefficients between genetic and geographic distance matrices (P > 0.05). These results show that eastern Canadian provinces are part of the same white pine blister rust epidemiological unit. Nursery distribution systems are controlled provincially, with virtually no seedling movement among provinces; therefore, infected nursery material may not play an important role in the dissemination of this disease. Long-distance spore dispersal across provincial boundaries appears to be an epidemiologically important factor for this pathogen.

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Contemporary Genetic Structure, Phylogeography and Past Demographic Processes of Wild Boar Sus scrofa Population in Central and Eastern Europe

PLoS ONE ◽

10.1371/journal.pone.0091401 ◽

2014 ◽

Vol 9 (3) ◽

pp. e91401 ◽

Cited By ~ 19

Author(s):

Szilvia Kusza ◽

Tomasz Podgórski ◽

Massimo Scandura ◽

Tomasz Borowik ◽

András Jávor ◽

...

Keyword(s):

Genetic Structure ◽

Eastern Europe ◽

Wild Boar ◽

Sus Scrofa ◽

Central And Eastern Europe ◽

Demographic Processes

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Demography and Evolution in an Immigrant Ethnic Community: Hungarian Settlement, Louisiana, USA

Journal of Biosocial Science ◽

10.1017/s0021932000014516 ◽

1983 ◽

Vol 15 (2) ◽

pp. 223-236 ◽

Cited By ~ 1

Author(s):

Tibor Koertvelyessy

Keyword(s):

Gene Flow ◽

Natural Selection ◽

Genetic Drift ◽

Demographic Characteristics ◽

Ethnic Population ◽

Marriage Patterns ◽

Evolutionary Forces ◽

Evolutionary Force ◽

Demographic Processes ◽

Over Time

SummaryThis paper describes the fertility, mortality, and marriage patterns of the Hungarian Settlement, Louisiana, USA, immigrant ethnic population and relates these demographic processes to the evolutionary forces of natural selection, genetic drift, and gene flow. The results indicate that the maximum opportunity for natural selection decreased over time, and natural selection could have operated in the case of this population at only a very moderate level. The demographic characteristics of this population suggest that genetic drift may be important as an agent of microdifferentiation. Gene flow, however, appears to be the most important evolutionary force in this population. The process, based on the increasing incorporation of non-Hungarians into the gene pool, is causing the breakdown of this ethnic/genetic isolate.

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Psychology 2.0: The Emergence of Individuality

10.31234/osf.io/m87an ◽

2019 ◽

Author(s):

Andrei Popa

Keyword(s):

Genetic Structure ◽

Human Development ◽

Systems Change ◽

Change Over Time ◽

Physical Systems ◽

Evolutionary Forces ◽

Genetic Structure Of Populations ◽

Physical Forces ◽

Over Time

Physical forces acting on particles explain how physical systems change over time. Evolutionary forces acting on populations of genomes explain change in the genetic structure of populations across generations. The dynamics of human development - i.e., learning, or change in psychological systems, are not yet understood. This is a step in that direction.

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Small-scale genetic structure in a stream-dwelling caddisfly in eastern Canada

Marine and Freshwater Research ◽

10.1071/mf13268 ◽

2015 ◽

Vol 66 (5) ◽

pp. 459

Author(s):

J. A. Addison ◽

A. L. Einfeldt ◽

N. N. Kang ◽

S. J. Walde

Keyword(s):

Genetic Diversity ◽

Genetic Structure ◽

Population Genetic ◽

Spatial Scales ◽

Small Scale ◽

Random Genetic Drift ◽

Eastern Canada ◽

Surficial Geology ◽

Phylogeographic Break ◽

Demographic Processes

We used mitochondrial DNA (cytochrome c oxidase subunit I) to examine the population genetic structure and phylogeography for 12 populations of a widely distributed predatory caddisfly (Rhyacophila minor) in small, unconnected streams along a 45-km stretch of North Mountain, Nova Scotia, Canada. We detected patterns of strong genetic subdivision (FST=0.312) with streams separated by >3.5km being significantly different whereas adjacent streams were not (no significant FST values), suggesting some, but very limited, current overland dispersal by adults. A significant phylogeographic break was found between eastern and western populations, corresponding to changes in bedrock and surficial geology. Genetic diversity within the streams was positively correlated with watershed size and the spatial variation in geology. We conclude that genetic divergence among populations of R. minor is a result of dispersal barriers and the accumulation of differences among the streams due to random genetic drift. Our study suggests that a better understanding of how dispersal interacts with landscape features at small spatial scales will improve our ability to link the movement of individuals to ecological and demographic processes.

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Migration and genetic diversity in an island population: Karkar, Papua New Guinea

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1978.0067 ◽

1978 ◽

Vol 202 (1147) ◽

pp. 269-295 ◽

Cited By ~ 11

Keyword(s):

Genetic Diversity ◽

Genetic Structure ◽

Age Groups ◽

New Guinea ◽

Genetic Distances ◽

Human Populations ◽

Island Population ◽

Evolutionary Forces ◽

Married Individuals ◽

Linguistic Groups

This paper examines genetic diversity on Karkar Island, Papna New Guinea, and its relation to patterns of migration within and between the two linguistic groups (Waskia and Takia) on the island. Exchange between linguistic groups is found to be small: less than 3 % of married individuals living in one linguistic group were born in the other. There is evidence of a secular trend in movement with significantly greater proportions of younger married individuals living outside their village group of birth. The migration patterns are examined by principal coordinate analysis of kinship coefficients derived from three sets of migration probabilities: ages 15—29, 30—44, 45 and over. For all three age groups the linguistic division is preserved and there is broad agreement between relatedness and the geographical arrangement of the village groups. The 22 polymorphic genetic systems examined show considerable diversity, most of which is within or between village groups in the same linguistic division. The greater level of diversity between Takia groups is consistent with their greater isolation from one another. Genetic distances between village groups show good agreement with geographical distances and there is no overlap between Waskia and Takia. The present-day genetic structure of Karkar Island can be interpreted as being largely the result of the interplay of migration and drift processes. The paper considers the use of analyses of this kind in establishing the magnitude and role of evolutionary forces operating on the genetic structure of human populations and the problems of unravelling rigorously and in detail the historical development of this structure.

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