Evolutionary dynamics of cycle length in pearl millet: the role of farmer’s practices and gene flow

AbstractExplicitly accounting for phenotypic differentiation together with environmental heterogeneity is crucial to understand the evolutionary dynamics in hybrid zones. Species showing intra-specific variation in phenotypic traits that meet across environmentally heterogeneous regions constitute excellent natural settings to study the role of phenotypic differentiation and environmental factors in shaping the spatial extent and patterns of admixture in hybrid zones. We studied three environmentally distinct contact zones where morphologically and reproductively divergent subspecies of Salamandra salamandra co-occur: the pueriparous S. s. bernardezi that is mostly parapatric to its three larviparous subspecies neighbours. We used a landscape genetics framework to: (i) characterise the spatial location and extent of each contact zone; (ii) assess patterns of introgression and hybridization between subspecies pairs; and (iii) examine the role of environmental heterogeneity in the evolutionary dynamics of hybrid zones. We found high levels of introgression between parity modes, and between distinct phenotypes, thus demonstrating the evolution to pueriparity alone or morphological differentiation do not lead to reproductive isolation between these highly divergent S. salamandra morphotypes. However, we detected substantial variation in patterns of hybridization across contact zones, being lower in the contact zone located on a topographically complex area. We highlight the importance of accounting for spatial environmental heterogeneity when studying evolutionary dynamics of hybrid zones.

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Premating barriers in young sympatric snail species

Scientific Reports ◽

10.1038/s41598-021-84407-2 ◽

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.

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Molecular Signatures of Reticulate Evolution within the Complex of European Pine Taxa

Forests ◽

10.3390/f12040489 ◽

2021 ◽

Vol 12 (4) ◽

pp. 489

Author(s):

Bartosz Łabiszak ◽

Witold Wachowiak

Keyword(s):

Gene Flow ◽

Reticulate Evolution ◽

Modeling Framework ◽

Closely Related Species ◽

Interspecific Gene Flow ◽

Nucleotide Sequence Variation ◽

History Of ◽

Best Fitting ◽

Species Integrity

Speciation mechanisms, including the role of interspecific gene flow and introgression in the emergence of new species, are the major focus of evolutionary studies. Inference of taxonomic relationship between closely related species may be challenged by past hybridization events, but at the same time, it may provide new knowledge about mechanisms responsible for the maintenance of species integrity despite interspecific gene flow. Here, using nucleotide sequence variation and utilizing a coalescent modeling framework, we tested the role of hybridization and introgression in the evolutionary history of closely related pine taxa from the Pinus mugo complex and P. sylvestris. We compared the patterns of polymorphism and divergence between taxa and found a great overlap of neutral variation within the P. mugo complex. Our phylogeny reconstruction indicated multiple instances of reticulation events in the past, suggesting an important role of interspecific gene flow in the species divergence. The best-fitting model revealed P. mugo and P. uncinata as sister species with basal P. uliginosa and asymmetric migration between all investigated species after their divergence. The magnitude of interspecies gene flow differed greatly, and it was consistently stronger from representatives of P. mugo complex to P. sylvestris than in the opposite direction. The results indicate the prominent role of reticulation evolution in those forest trees and provide a genetic framework to study species integrity maintained by selection and local adaptation.

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Introgression between non-sister species of honeyeaters (Aves: Meliphagidae) several million years after speciation

Biological Journal of the Linnean Society ◽

10.1093/biolinnean/blz129 ◽

2019 ◽

Vol 128 (3) ◽

pp. 583-591

Author(s):

Leo Joseph ◽

Alex Drew ◽

Ian J Mason ◽

Jeffrey L Peters

Keyword(s):

Gene Flow ◽

Reproductive Isolation ◽

Sex Chromosomes ◽

Common Ancestor ◽

Sister Species ◽

Species Boundaries ◽

North Eastern ◽

The City

Abstract We reassessed whether two parapatric non-sister Australian honeyeater species (Aves: Meliphagidae), varied and mangrove honeyeaters (Gavicalis versicolor and G. fasciogularis, respectively), that diverged from a common ancestor c. 2.5 Mya intergrade in the Townsville area of north-eastern Queensland. Consistent with a previous specimen-based study, by using genomics methods we show one-way gene flow for autosomal but not Z-linked markers from varied into mangrove honeyeaters. Introgression barely extends south of the area of parapatry in and around the city of Townsville. While demonstrating the long-term porosity of species boundaries over several million years, our data also suggest a clear role of sex chromosomes in maintaining reproductive isolation.

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Gillespie eco‐evolutionary models ( GEM s) reveal the role of heritable trait variation in eco‐evolutionary dynamics

Ecology and Evolution ◽

10.1002/ece3.1959 ◽

2016 ◽

Vol 6 (4) ◽

pp. 935-945 ◽

Cited By ~ 18

Author(s):

John P. DeLong ◽

Jean P. Gibert

Keyword(s):

Evolutionary Dynamics ◽

Evolutionary Models ◽

Trait Variation ◽

Heritable Trait

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The Genomic Ecosystem of Transposable Elements in Maize

10.1101/559922 ◽

2019 ◽

Cited By ~ 18

Author(s):

Michelle C. Stitzer ◽

Sarah N. Anderson ◽

Nathan M. Springer ◽

Jeffrey Ross-Ibarra

Keyword(s):

Transposable Elements ◽

Evolutionary Dynamics ◽

Phenotypic Diversity ◽

Flowering Plant ◽

Genome Wide ◽

Family Level ◽

Genomic Environment ◽

Single Category ◽

The Impact

Transposable elements (TEs) constitute the majority of flowering plant DNA, reflecting their tremendous success in subverting, avoiding, and surviving the defenses of their host genomes to ensure their selfish replication. More than 85% of the sequence of the maize genome can be ascribed to past transposition, providing a major contribution to the structure of the genome. Evidence from individual loci has informed our understanding of how transposition has shaped the genome, and a number of individual TE insertions have been causally linked to dramatic phenotypic changes. But genome-wide analyses in maize and other taxa have frequently represented TEs as a relatively homogeneous class of fragmentary relics of past transposition, obscuring their evolutionary history and interaction with their host genome. Using an updated annotation of structurally intact TEs in the maize reference genome, we investigate the family-level ecological and evolutionary dynamics of TEs in maize. Integrating a variety of data, from descriptors of individual TEs like coding capacity, expression, and methylation, as well as similar features of the sequence they inserted into, we model the relationship between these attributes of the genomic environment and the survival of TE copies and families. Our analyses reveal a diversity of ecological strategies of TE families, each representing the evolution of a distinct ecological niche allowing survival of the TE family. In contrast to the wholesale relegation of all TEs to a single category of junk DNA, these differences generate a rich ecology of the genome, suggesting families of TEs that coexist in time and space compete and cooperate with each other. We conclude that while the impact of transposition is highly family- and context-dependent, a family-level understanding of the ecology of TEs in the genome can refine our ability to predict the role of TEs in generating genetic and phenotypic diversity.‘Lumping our beautiful collection of transposons into a single category is a crime’-Michael R. Freeling, Mar. 10, 2017

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Gene flow within the M evolutionary lineage ofApis mellifera: role of the Pyrenees, isolation by distance and post-glacial re-colonization routes in the western Europe

Apidologie ◽

10.1051/apido:2007007 ◽

2007 ◽

Vol 38 (2) ◽

pp. 141-155 ◽

Cited By ~ 52

Author(s):

Irati Miguel ◽

Mikel Iriondo ◽

Lionel Garnery ◽

Walter S. Sheppard ◽

Andone Estonba

Keyword(s):

Gene Flow ◽

Western Europe ◽

Isolation By Distance ◽

Colonization Routes ◽

Evolutionary Lineage

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The role of biotic interactions in invasion ecology: theories and hypotheses.

Plant invasions: the role of biotic interactions ◽

10.1079/9781789242171.0002 ◽

2020 ◽

pp. 26-44

Author(s):

Cang Hui ◽

◽

Pietro Landi ◽

Guillaume Latombe ◽

◽

...

Keyword(s):

Native Species ◽

Evolutionary Dynamics ◽

Biotic Interactions ◽

Evolutionary Games ◽

Invasion Ecology ◽

Ecological Communities ◽

Dynamic Interactions ◽

Ecological Fitting ◽

And Function

Changes in biotic interactions in the native and invaded range can enable a non-native species to establish and spread in novel environments. Invasive non-native species can in turn generate impacts in recipient systems partly through the changes they impose on biotic interactions; these interactions can lead to altered ecosystem processes in the recipient systems. This chapter reviews models, theories and hypotheses on how invasion performance and impact of introduced species in recipient ecosystems can be conjectured according to biotic interactions between native and non-native species. It starts by exploring the nature of biotic interactions as ensembles of ecological and evolutionary games between individuals of both the same and different groups. This allows us to categorize biotic interactions as direct and indirect (i.e. those involving more than two species) that emerge from both coevolution and ecological fitting during community assembly and invasion. We then introduce conceptual models that can reveal the ecological and evolutionary dynamics between interacting non-native and resident species in ecological networks and communities. Moving from such theoretical grounding, we review 20 hypotheses that have been proposed in invasion ecology to explain the invasion performance of a single non-native species, and seven hypotheses relating to the creation and function of assemblages of non-native species within recipient ecosystems. We argue that, although biotic interactions are ubiquitous and quintessential to the assessment of invasion performance, they are nonetheless difficult to detect and measure due to strength dependency on sampling scales and population densities, as well as the non-equilibrium transient dynamics of ecological communities and networks. We therefore call for coordinated efforts in invasion science and beyond, to devise and review approaches that can rapidly map out the entire web of dynamic interactions in a recipient ecosystem.

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