Nuclear microsatellites reveal population genetic structuring and fine-scale pattern of hybridization in the Japanese mantis shrimp Oratosquilla oratoria

The interplay between historical and contemporary processes can produce complex patterns of genetic differentiation in the marine realm. Recent mitochondrial and nuclear sequence analyses revealed cryptic speciation in the Japanese mantis shrimp Oratosquilla oratoria. Herein, we applied nuclear microsatellite markers to examine patterns and causes of genetic differentiation in this morphotaxon. Population structure analyses revealed two genetically divergent and geographically structured clades in O. oratoria, one dominating the temperate zone of the Northwestern (NW) Pacific and the other occurring in the subtropical and tropical waters where are influenced by the Kuroshio Current. Two sympatric zones, one around the Changjiang Estuary in China coast and the other in the northern Japan Sea, were demonstrated to be hybrid zones where introgressive hybridization occurred asymmetrically. The interaction between historical climate shifts and contemporary factors (e.g., freshwater discharge, temperature gradient and isolation by distance) may contribute to the present-day genetic architecture in the Japanese mantis shrimp. Range shift induced by climate changes and oceanographic factors may promote hybridization and gene flow between the O. oratoria complex. Our results provide insights into the interacting mechanisms that give rise to diversification and speciation of coastal species in the NW Pacific.

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Low chloroplast diversity despite phylogenetically divergent haplotypes in Japanese populations of Ailanthus altissima (Simaroubaceae)

Botany ◽

10.1139/cjb-2012-0159 ◽

2013 ◽

Vol 91 (3) ◽

pp. 148-154 ◽

Cited By ~ 15

Author(s):

Hiroyuki Kurokochi ◽

Yoko Saito ◽

Misaki Chuman ◽

Yuji Ide

Keyword(s):

Genetic Differentiation ◽

Chloroplast Dna ◽

Isolation By Distance ◽

The Other ◽

Dna Polymorphisms ◽

Ailanthus Altissima ◽

Molecular Variation ◽

Chinese Populations ◽

The Past ◽

Introduced Populations

Ailanthus altissima (Mill.) Swingle (Simaroubaceae) has succeeded in expanding its distribution widely over the past 100 years in Japan. We investigated which maternal lines of A. altissima are expanding in Japan and whether the introduced populations are different in various regions of Japan. Chloroplast DNA polymorphisms were analyzed on A. altissima trees (n = 449) sampled from 64 nonindigenous Japanese populations and four indigenous Chinese populations. Six haplotypes were identified. Three haplotypes (H1, H2, and H3) were observed in Japan, whereas four (H3, H4, H5, and H6) were detected in Chinese populations. Most A. altissima trees in Japan harbor either H1 or H3, and these two haplotypes were not genetically similar. Analysis of molecular variation showed some genetic differentiation among populations. In addition, significant isolation by distance was not detected. Twenty-two Japanese populations contained two haplotypes within each population, whereas the other 42 Japanese populations were composed of only one haplotype. These results indicate that Japanese populations of A. altissima may have derived from a limited number of seed introductions, but they were then widely spread in various regions.

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Genetic differentiation in an endangered and strongly philopatric, migrant shorebird

BMC Ecology and Evolution ◽

10.1186/s12862-021-01855-0 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Nelli Rönkä ◽

Veli-Matti Pakanen ◽

Angela Pauliny ◽

Robert L. Thomson ◽

Kimmo Nuotio ◽

...

Keyword(s):

Gene Flow ◽

Genetic Differentiation ◽

Environmental Changes ◽

Isolation By Distance ◽

Population Subdivision ◽

Genetic Structuring ◽

Long Distance ◽

Mobile Species ◽

High Dispersal ◽

The Baltic

Abstract Background Populations living in fragmented habitats may suffer from loss of genetic variation and reduced between-patch dispersal, which are processes that can result in genetic differentiation. This occurs frequently in species with reduced mobility, whereas genetic differentiation is less common among mobile species such as migratory birds. The high dispersal capacity in the latter species usually allows for gene flow even in fragmented landscapes. However, strongly philopatric behaviour can reinforce relative isolation and the degree of genetic differentiation. The Southern Dunlin (Calidris alpina schinzii) is a philopatric, long-distance migratory shorebird and shows reduced dispersal between isolated breeding patches. The endangered population of the Southern Dunlin breeding at the Baltic Sea has suffered from habitat deterioration and fragmentation of coastal meadows. We sampled DNA across the entire population and used 12 polymorphic microsatellite loci to examine whether the environmental changes have resulted in genetic structuring and loss of variation. Results We found a pattern of isolation-by-distance across the whole Baltic population and genetic differentiation between local populations, even within the southern Baltic. Observed heterozygosity was lower than expected throughout the range and internal relatedness values were positive indicating inbreeding. Conclusions Our results provide long-term, empirical evidence for the theoretically expected links between habitat fragmentation, population subdivision, and gene flow. They also demonstrate a rare case of genetic differentiation between populations of a long-distance migratory species. The Baltic Southern Dunlin differs from many related shorebird species that show near panmixia, reflecting its philopatric life history and the reduced connectivity of its breeding patches. The results have important implications as they suggest that reduced connectivity of breeding habitats can threaten even long-distance migrants if they show strong philopatry during breeding. The Baltic Southern Dunlin warrants urgent conservation efforts that increase functional connectivity and gene flow between breeding areas.

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Genetic differentiation of Sorbus torminalis in Eastern Europe as determined by microsatellite markers

Biologia ◽

10.2478/s11756-010-0082-y ◽

2010 ◽

Vol 65 (5) ◽

Cited By ~ 4

Author(s):

Veronika Kučerová ◽

Martin Honec ◽

Ladislav Paule ◽

Petar Zhelev ◽

Dušan Gömöry

Keyword(s):

Genetic Variation ◽

Gene Flow ◽

Genetic Differentiation ◽

Bayesian Methods ◽

Isolation By Distance ◽

General Pattern ◽

The Other ◽

Hand Model ◽

Sorbus Torminalis ◽

Nuclear Microsatellite

AbstractThe genetic variation in fourteen Sorbus torminalis (L.) Crantz. populations distributed over the eastern and south-eastern part of its range was studied using seven nuclear microsatellite loci. The differentiation level was relatively high (F ST = 0.228), as expected for a species with a fragmented range. The distance-based approach to the analysis of differentiation patterns (neighbour-joining tree based on pairwise coefficients of differentiation) did not reveal a clear geographical structure. On the other hand, model-based Bayesian methods (BAPS and STRUCTURE) gave geographically continuous clusters of populations. The occurrence of populations deviating strongly from the general pattern is attributed to founder effect. In spite of a generally high differentiation, a significant isolation-by-distance pattern was found, which might be a consequence of postglacial migration and gene flow among descendants of different refugia.

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Genetic population structure of the monogenean parasite Gyrodactylus thymalli and its host European grayling (Thymallus thymallus) in a large Norwegian lake

Hydrobiologia ◽

10.1007/s10750-020-04431-7 ◽

2020 ◽

Author(s):

Ruben Alexander Pettersen ◽

Claudia Junge ◽

Kjartan Østbye ◽

Tor Atle Mo ◽

Leif Asbjørn Vøllestad

Keyword(s):

Genetic Structure ◽

Evolutionary Biology ◽

Isolation By Distance ◽

Genetic Structuring ◽

Thymallus Thymallus ◽

Homing Behavior ◽

Genetic Population ◽

Monogenean Parasite ◽

European Grayling ◽

Genetic Clusters

Abstract Understanding how populations are structured in space and time is a central question in evolutionary biology. Parasites and their hosts are assumed to evolve together, however, detailed understanding of mechanisms leading to genetic structuring of parasites and their hosts are lacking. As a parasite depends on its host, studying the genetic structure of both parasite and host can reveal important insights into these mechanisms. Here, genetic structure of the monogenean parasite Gyrodactylus thymalli and its host the European grayling (Thymallus thymallus) was investigated in 10 tributaries draining into the large Lake Mjøsa in Norway. The population genetic structure of spawning grayling was studied using microsatellite genotyping, while G. thymalli was studied by sequencing a mitochondrial DNA gene (dehydrogenase subunit 5). Two main genetic clusters were revealed in grayling, one cluster comprising grayling from the largest spawning population, while the remaining tributaries formed the second cluster. For both taxa, some genetic differentiation was observed among tributaries, but there was no clear isolation-by-distance signature. The structuring was stronger for the host than for the parasite. These results imply that moderate to high levels of gene flow occur among the sub-populations of both taxa. The high parasite exchange among tributaries could result from a lack of strong homing behavior in grayling as well as interactions among individual fish outside of the spawning season, leading to frequent mixing of both host and parasite.

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Genetic differentiation in Scottish populations of the pine beauty moth, Panolis flammea (Lepidoptera: Noctuidae)

Bulletin of Entomological Research ◽

10.1079/ber2005384 ◽

2005 ◽

Vol 95 (6) ◽

pp. 517-526 ◽

Cited By ~ 3

Author(s):

A.J. Lowe ◽

B.J. Hicks ◽

K. Worley ◽

R.A. Ennos ◽

J.D. Morman ◽

...

Keyword(s):

Genetic Differentiation ◽

Scots Pine ◽

Rapd Analysis ◽

Isolation By Distance ◽

Long Distance ◽

Panolis Flammea ◽

Colonization Dynamics ◽

Low Levels ◽

Lepidoptera Noctuidae ◽

Limited Exchange

AbstractPine beauty moth, Panolis flammea (Denis & Schiffermüller), is a recent but persistent pest of lodgepole pine plantations in Scotland, but exists naturally at low levels within remnants and plantations of Scots pine. To test whether separate host races occur in lodgepole and Scots pine stands and to examine colonization dynamics, allozyme, randomly amplified polymorphic DNA (RAPD) and mitochondrial variation were screened within a range of Scottish samples. RAPD analysis indicated limited long distance dispersal (FST = 0.099), and significant isolation by distance (P < 0.05); but that colonization between more proximate populations was often variable, from extensive to limited exchange. When compared with material from Germany, Scottish samples were found to be more diverse and significantly differentiated for all markers. For mtDNA, two highly divergent groups of haplotypes were evident, one group contained both German and Scottish samples and the other was predominantly Scottish. No genetic differentiation was evident between P. flammea populations sampled from different hosts, and no diversity bottleneck was observed in the lodgepole group. Indeed, lodgepole stands appear to have been colonized on multiple occasions from Scots pine sources and neighbouring populations on different hosts are close to panmixia.

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