scholarly journals Gene Introgression among Closely Related Species in Sympatric Populations: A Case Study of Three Walnut (Juglans) Species

Forests ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 965 ◽  
Author(s):  
Dang ◽  
Yue ◽  
Zhang ◽  
Zhao ◽  
Zhao
Keyword(s):  
Gene Flow ◽  
Related Species ◽  
Expressed Sequence Tag ◽  
Juglans Regia ◽  
Natural Hybridization ◽  
Private Allele ◽  
Gene Introgression ◽  
Sympatric Populations ◽  
Closely Related Species ◽  
Biogeographic History

Gene introgression usually results from natural hybridization occurring among closely related species in sympatric populations. In this study, we discussed two rare and frequent gene flow phenomena between three species of Juglans plants and analyzed the possible causes for the difference. We collected 656 individuals from 40 populations of Persian walnut (Juglans regia L.), Chinese walnut (J. cathayensis Dode), and Iron walnut (J. sigillata Dode) that were genotyped at 17 expressed sequence tag simple sequence repeat (EST-SSR) loci to analyze the introgressions between J. regia and J. cathayensis, and J. regia and J. sigillata. Our study compared the spatial patterns of expected heterozygosity (HE), allelic richness (Rs), and private allele richness (PAR) so as to vividly infer the biogeographic history of related species of Juglans in the two regions. The results of the PCoA, UPGMA, and STRUCTURE analyses showed that all J. regia and J. sigillata populations clustered into one group, and the J. cathayensis populations clustered into the other group. The results of the historical gene flow analysis indicated that J. regia and J. sigillata have no genetic barriers, and the directional gene flow is mainly from J. regia to J. sigillata. For the three species of Juglans, all the above results indicated that gene flow was common among the same group of Juglans, and only rare and low-level gene flow appeared in distinct groups. Therefore, our study revealed multiple phenomena of gene flow and introgression among closely related species in sympatric populations, thereby providing a theoretical basis for the genetic evolution of the genus Juglans.

scholarly journals Premating barriers in young sympatric snail species

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Arina L. Maltseva ◽  
Marina A. Varfolomeeva ◽  
Arseniy A. Lobov ◽  
Polina O. Tikanova ◽  
Egor A. Repkin ◽  
...  
Keyword(s):  
Gene Flow ◽  
Snail Species ◽  
Sympatric Populations ◽  
Gastropod Species ◽  
Shell Size ◽  
Closely Related Species ◽  
Partial Canonical Correspondence Analysis ◽  
In The Wild ◽  
Isolation Index

AbstractSympatric coexistence of recently diverged species raises the question of barriers restricting the gene flow between them. Reproductive isolation may be implemented at several levels, and the weakening of some, e.g. premating, barriers may require the strengthening of the others, e.g. postcopulatory ones. We analysed mating patterns and shell size of mates in recently diverged closely related species of the subgenus Littorina Neritrema (Littorinidae, Caenogastropoda) in order to assess the role of premating reproductive barriers between them. We compared mating frequencies observed in the wild with those expected based on relative densities using partial canonical correspondence analysis. We introduced the fidelity index (FI) to estimate the relative accuracy of mating with conspecific females and precopulatory isolation index (IPC) to characterize the strength of premating barriers. The species under study, with the exception of L. arcana, clearly demonstrated preferential mating with conspecifics. According to FI and IPC, L. fabalis and L. compressa appeared reliably isolated from their closest relatives within Neritrema. Individuals of these two species tend to be smaller than those of the others, highlighting the importance of shell size changes in gastropod species divergence. L. arcana males were often found in pairs with L. saxatilis females, and no interspecific size differences were revealed in this sibling species pair. We discuss the lack of discriminative mate choice in the sympatric populations of L. arcana and L. saxatilis, and possible additional mechanisms restricting gene flow between them.

scholarly journals Genetic analysis of a wild-caught hybrid between non-sister Heliconius butterfly species

2007 ◽  
Vol 3 (6) ◽  
pp. 660-663 ◽  
Author(s):  
Kanchon K Dasmahapatra ◽  
Armando Silva-Vásquez ◽  
Jae-Woo Chung ◽  
James Mallet
Keyword(s):  
Gene Flow ◽  
Genetic Analysis ◽  
Related Species ◽  
Species Boundaries ◽  
Butterfly Species ◽  
Distant Hybridization ◽  
Closely Related Species ◽  
Naturally Occurring ◽  
Heliconius Melpomene ◽  
Wing Coloration

Interspecific hybridization occurs regularly in wild Heliconius butterflies, although hybrid individuals are usually very rare. However, hybridization generally occurs only between the most closely related species. We report a rare naturally occurring hybrid between non-sister species and carry out the first genetic analysis of such distant hybridization. Mitochondrial and nuclear genes indicate that the specimen is an F 1 hybrid between a female Heliconius ethilla and a male Heliconius melpomene , originating from a group of 13 species estimated to have diverged over 2.5 Myr ago. The presence of such distant natural hybrids, together with evidence for backcrossing, suggests that gene flow across species boundaries can take place long after speciation. Adaptive genes such as those involved in wing coloration could thus be widely shared among members of this highly mimetic genus.

scholarly journals Head Transcriptomes of Two Closely Related Species of Fruit Flies of theAnastrepha fraterculusGroup Reveals Divergent Genes in Species with Extensive Gene Flow

2016 ◽  
Vol 6 (10) ◽  
pp. 3283-3295 ◽  
Author(s):  
Victor Borges Rezende ◽  
Carlos Congrains ◽  
André Luís A. Lima ◽  
Emeline Boni Campanini ◽  
Aline Minali Nakamura ◽  
...  
Keyword(s):  
Gene Flow ◽  
Related Species ◽  
Fruit Flies ◽  
Closely Related Species

scholarly journals Divergence and introgression among the virilis group of Drosophila

2022 ◽  
Author(s):  
Leeban Yusuf ◽  
Venera Tyukmaeva ◽  
Anneli Hoikkala ◽  
Michael G Ritchie
Keyword(s):  
Gene Flow ◽  
Related Species ◽  
De Novo ◽  
Phylogenetic Reconstruction ◽  
Sequence Divergence ◽  
Sexual Isolation ◽  
Whole Genome Sequencing Data ◽  
Sequencing Data ◽  
Closely Related Species ◽  
Virilis Group

Speciation with gene flow is now widely regarded as common. However, the frequency of introgression between recently diverged species and the evolutionary consequences of gene flow are still poorly understood. The virilis group of Drosophila contains around a dozen species that are geographically widespread and show varying levels of pre-zygotic and post-zygotic isolation. Here, we utilize de novo genome assemblies and whole-genome sequencing data to resolve phylogenetic relationships and describe patterns of introgression and divergence across the group. We suggest that the virilis group consists of three, rather than the traditional two, subgroups. We found evidence of pervasive phylogenetic discordance caused by ancient introgression events between distant lineages within the group, and much more recent gene flow between closely-related species. When assessing patterns of genome-wide divergence in species pairs across the group, we found no consistent genomic evidence of a disproportionate role for the X chromosome. Some genes undergoing rapid sequence divergence across the group were involved in chemical communication and may be related to the evolution of sexual isolation. We suggest that gene flow between closely-related species has potentially had an impact on lineage-specific adaptation and the evolution of reproductive barriers. Our results show how ancient and recent introgression confuse phylogenetic reconstruction, and suggest that shared variation can facilitate adaptation and speciation.

scholarly journals Whole-Genome Diversification Analysis of the Hornbeam Species Reveals Speciation and Adaptation Among Closely Related Species

2021 ◽  
Vol 12 ◽  
Author(s):  
Zeyu Zheng ◽  
Ying Li ◽  
Minjie Li ◽  
Guiting Li ◽  
Xin Du ◽  
...  
Keyword(s):  
Gene Flow ◽  
Related Species ◽  
Biological Diversity ◽  
Population Decline ◽  
Evolutionary Process ◽  
Speciation Analysis ◽  
Central Place ◽  
Future Research ◽  
Effective Population ◽  
Closely Related Species

Speciation is the key evolutionary process for generating biological diversity and has a central place in evolutionary and ecological research. How species diverge and adapt to different habitats is one of the most exciting areas in speciation studies. Here, we sequenced 55 individuals from three closely related species in the genus Carpinus: Carpinus tibetana, Carpinus monbeigiana, and Carpinus mollicoma to understand the strength and direction of gene flow and selection during the speciation process. We found low genetic diversity in C. tibetana, which reflects its extremely small effective population size. The speciation analysis between C. monbeigiana and C. mollicoma revealed that both species diverged ∼1.2 Mya with bidirectional gene flow. A total of 291 highly diverged genes, 223 copy number variants genes, and 269 positive selected genes were recovered from the two species. Genes associated with the diverged and positively selected regions were mainly involved in thermoregulation, plant development, and response to stress, which included adaptations to their habitats. We also found a great population decline and a low genetic divergence of C. tibetana, which suggests that this species is extremely vulnerable. We believe that the current diversification and adaption study and the important genomic resource sequenced herein will facilitate the speciation studies and serve as an important methodological reference for future research.

scholarly journals The relationship between gene flow and population difference during secondary contact between butterfly sister species

2020 ◽  
Author(s):  
Erik D. Nelson ◽  
Qian Cong ◽  
Nick V. Grishin
Keyword(s):  
Gene Flow ◽  
Related Species ◽  
Missing Values ◽  
Sudden Change ◽  
Secondary Contact ◽  
Z Chromosome ◽  
Population Difference ◽  
Hybrid Fitness ◽  
Closely Related Species ◽  
Index Data

AbstractClosely related species of butterfly sampled from southern suture zones in North America exhibit a continuous pattern of gene flow and population difference measures (index values) for autosomes, but not for the Z chromosome; When populations are compared through their Z chromosomes, index values obtained from samples of the same species are separated from those of closely related species by a gap of “missing” values, suggesting a discrete “on–off” criterion for species delimitation. Here, we explore the possibility that some, or all of the index data for suture zones reflects secondary contact between species formed in glacial refugia. We simulate fusion of butterfly populations limited by negative fitness interactions between genes in hybrids, assuming that interactions between autosomes and the Z chromosome are stronger than those among autosomes, and that hybrid fitness effects conform to Haldane’s rule. We find that weakly interbreeding populations trace out a path toward equilibrium consistent with the data for butterfly suture zones, in which index values for the Z chromosome lag behind those for autosomes, leading to a similar gap of missing values when species become indistinguishable through their autosomes, but no evidence of a sudden change in index values for the Z chromosome on longer timescales. As a result, we find that the gap can be explained by a process in which the pattern of index data for the Z chromosome is, ultimately, continuous.

scholarly journals Genetic architecture of a key reproductive isolation trait differs between sympatric and non-sympatric sister species of Lake Victoria cichlids

2020 ◽  
Vol 287 (1924) ◽  
pp. 20200270
Author(s):  
Anna F. Feller ◽  
Marcel P. Haesler ◽  
Catherine L. Peichel ◽  
Ole Seehausen
Keyword(s):  
Gene Flow ◽  
Reproductive Isolation ◽  
Related Species ◽  
Genetic Architecture ◽  
Lake Victoria ◽  
Sympatric Species ◽  
Sister Species ◽  
Species Pair ◽  
Closely Related Species ◽  
Nuptial Coloration

One hallmark of the East African cichlid radiations is the rapid evolution of reproductive isolation that is robust to full sympatry of many closely related species. Theory predicts that species persistence and speciation in sympatry with gene flow are facilitated if loci of large effect or physical linkage (or pleiotropy) underlie traits involved in reproductive isolation. Here, we investigate the genetic architecture of a key trait involved in behavioural isolation, male nuptial coloration, by crossing two sister species pairs of Lake Victoria cichlids of the genus Pundamilia and mapping nuptial coloration in the F2 hybrids. One is a young sympatric species pair, representative of an axis of colour motif differentiation, red-dorsum versus blue, that is highly recurrent in closely related sympatric species. The other is a species pair representative of colour motifs, red-chest versus blue, that are common in allopatric but uncommon in sympatric closely related species. We find significant quantitative trait loci (QTLs) with moderate to large effects (some overlapping) for red and yellow in the sympatric red-dorsum × blue cross, whereas we find no significant QTLs in the non-sympatric red-chest × blue cross. These findings are consistent with theory predicting that large effect loci or linkage/pleiotropy underlying mating trait differentiation could facilitate speciation and species persistence with gene flow in sympatry.

Sign in / Sign up

Export Citation Format

Share Document