Assessing early fitness consequences of exotic gene flow in the wild: a field study with Iberian pine relicts

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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Herbivore-induced plant vaccination. Part I. The orchestration of plant defenses in nature and their fitness consequences in the wild tobaccoNicotiana attenuata

The Plant Journal ◽

10.1111/j.1365-313x.2004.02076.x ◽

2004 ◽

Vol 38 (4) ◽

pp. 639-649 ◽

Cited By ~ 146

Author(s):

André Kessler ◽

Ian T. Baldwin

Keyword(s):

Plant Defenses ◽

Fitness Consequences ◽

In The Wild

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Unobtrusive Observation of Cycling Tourists in the Wild

International Journal of Mobile Human Computer Interaction ◽

10.4018/ijmhci.2014100102 ◽

2014 ◽

Vol 6 (4) ◽

pp. 22-42

Author(s):

Benjamin Poppinga ◽

Martin Pielot ◽

Wilko Heuten ◽

Susanne Boll

Keyword(s):

Field Study ◽

In Situ Observation ◽

In Situ Techniques ◽

In The Wild ◽

The Individual ◽

Post Hoc ◽

Real Challenge ◽

Unobtrusive Observation

The observation of cycling tourists is a real challenge. Traditional in-situ observation techniques fail as they threaten the intimateness of the experience and often interfere with the users' tasks. In post-hoc studies, like interviews, participants are unable to recap all details of their earlier experience accurately. This paper investigates how a hybrid, i.e., in-situ and post-hoc, observation approach can overcome the individual limitations and thereby provide detailed insights without disturbing the cyclists. The authors demonstrate the approach in a field study, where we observed 11 tourists with three unobtrusive in-situ techniques and used the gathered data to jog their memories in a post-hoc interview. They found that the observation technique allows to get detailed and accurate insights, and the communication between experimenter and participant becomes clearer. The authors conclude that hybrid observation would be valuable in other mobile field study settings.

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Gene Flow and Genetic Structure in the Wild–Weedy–Domesticated Complex of Phaseolus lunatus L. in its Mesoamerican Center of Domestication and Diversity

Crop Science ◽

10.2135/cropsci2006.04.0241 ◽

2007 ◽

Vol 47 (1) ◽

pp. 58-66 ◽

Cited By ~ 20

Author(s):

Jaime Martínez-Castillo ◽

Daniel Zizumbo-Villarreal ◽

Paul Gepts ◽

Patricia Colunga-GarcíaMarín

Keyword(s):

Gene Flow ◽

Genetic Structure ◽

Phaseolus Lunatus ◽

In The Wild

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Gene flow between diploid and tetraploid junipers - two contrasting evolutionary pathways in two Juniperus populations

BMC Evolutionary Biology ◽

10.1186/s12862-020-01688-3 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Perla Farhat ◽

Sonja Siljak-Yakovlev ◽

Nicolas Valentin ◽

Carlos Fabregat ◽

Silvia Lopez-Udias ◽

...

Keyword(s):

Genetic Diversity ◽

Gene Flow ◽

Ploidy Level ◽

High Genetic Diversity ◽

Iberian Range ◽

In The Wild ◽

Evolutionary Pathways

Abstract Background Gene flow and polyploidy have been found to be important in Juniperus evolution. However, little evidence has been published elucidating the association of both phenomena in juniper taxa in the wild. Two main areas were studied in Spain (Eastern Iberian Range and Sierra de Baza) with both diploid and tetraploid taxa present in sympatry. Gene flow and ploidy level were assessed for these taxa and the resulted offspring. Results Twenty-two allo-triploid hybrids between J. sabina var. sabina and J. thurifera were found in the Eastern Iberian Range population. However, in the Sierra de Baza population no triploids were found. Instead, 18 allo-tetraploid hybrids between two tetraploid taxa: J. sabina var. balkanensis and J. thurifera were discovered. High genetic diversity was exhibited among the tetraploid hybrids at Sierra de Baza, in contrast to the genetically identical triploid hybrids at the Eastern Iberian Range; this suggests meiotic difficulties within the triploid hybrids. In addition, unidirectional gene flow was observed in both studied areas. Conclusion Polyploidy and hybridization can be complementary partners in the evolution of Juniperus taxa in sympatric occurrences. Juniperus was shown to be an ideal coniferous model to study these two phenomena, independently or in concert.

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Gene Flow Between Introduced and Native Eucalyptus Species: Morphological Analysis of Tri-Species and Backcross Hybrids Involving E. nitens

Silvae Genetica ◽

10.1515/sg-2007-0019 ◽

2007 ◽

Vol 56 (1-6) ◽

pp. 127-133 ◽

Cited By ~ 7

Author(s):

C. Barbour ◽

B. M. Potts ◽

R. E. Vaillancourt

Keyword(s):

Gene Flow ◽

Second Generation ◽

Current Work ◽

F1 Hybrids ◽

Morphological Identification ◽

Eucalyptus Species ◽

Pure Species ◽

Backcross Hybrids ◽

In The Wild ◽

Species Hybrids

Summary Morphometric analyses were conducted on second-generation tri-species and backcross hybrids in Eucalyptus. These hybrids were all produced using pollen from two E. nitens x cordata F1 hybrids and controlled pollination techniques. Tri-species hybrids were created with E. gunnii, E. ovata and E. viminalis as females, while backcrosses were produced with E. cordata. Multivariate analysis of seedling characteristics indicated that eighty percent of the backcross hybrids fell within the morphological range of E. cordata. All three cross combinations of the tri-species hybrids were biased away from E. nitens and towards their maternal parent and E. cordata. The inclusion of data for first-generation (F1) hybrids between the pure parental species in the current work showed the F1’s to be easily distinguishable from pure species, compared to second-generation hybrids. The use of morphology for detecting second-generation hybridisation involving exotic plantation species and native eucalypt populations will therefore be unreliable, and identifies a need for preventing second-generation hybrids from establish in the wild. The current work, nevertheless, provides further demonstration of the effectiveness of morphological identification of F1 hybrids. The easy recognition of F1 hybrids will be useful in identifying sites and species at risk of exotic gene flow and enable the development of weeding programs that focus on removing exotic hybrids in the wild.

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Natural selection acts on Atlantic salmon major histocompatibility (MH) variability in the wild

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2006.0053 ◽

2007 ◽

Vol 274 (1611) ◽

pp. 861-869 ◽

Cited By ~ 34

Author(s):

Elvira de Eyto ◽

Philip McGinnity ◽

Sofia Consuegra ◽

Jamie Coughlan ◽

Jarle Tufto ◽

...

Keyword(s):

Natural Selection ◽

Atlantic Salmon ◽

Balancing Selection ◽

Natural Populations ◽

Class Ii ◽

Major Histocompatibility ◽

Genotype Frequencies ◽

Fitness Consequences ◽

In The Wild ◽

Class Ii Alpha

Pathogen-driven balancing selection is thought to maintain polymorphism in major histocompatibility (MH) genes. However, there have been few empirical demonstrations of selection acting on MH loci in natural populations. To determine whether natural selection on MH genes has fitness consequences for wild Atlantic salmon in natural conditions, we compared observed genotype frequencies of Atlantic salmon ( Salmo salar ) surviving in a river six months after their introduction as eggs with frequencies expected from parental crosses. We found significant differences between expected and observed genotype frequencies at the MH class II alpha locus, but not at a MH class I-linked microsatellite or at seven non-MH-linked microsatellite loci. We therefore conclude that selection at the MH class II alpha locus was a result of disease-mediated natural selection, rather than any demographic event. We also show that survival was associated with additive allelic effects at the MH class II alpha locus. Our results have implications for both the conservation of wild salmon stocks and the management of disease in hatchery fish. We conclude that natural or hatchery populations have the best chance of dealing with episodic and variable disease challenges if MH genetic variation is preserved both within and among populations.

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Spontaneous gene flow from rapeseed ( Brassica napus ) to wild Brassica oleracea

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2006.3686 ◽

2006 ◽

Vol 273 (1605) ◽

pp. 3111-3115 ◽

Cited By ~ 30

Author(s):

Caroline S Ford ◽

Joël Allainguillaume ◽

Phil Grilli-Chantler ◽

Giulia Cuccato ◽

Charlotte J Allender ◽

...

Keyword(s):

Flow Cytometry ◽

Gene Flow ◽

Brassica Napus ◽

Microsatellite Markers ◽

Brassica Oleracea ◽

Brassica Rapa ◽

Environmental Risks ◽

Wild Relatives ◽

Similar Species ◽

In The Wild

Research on the environmental risks of gene flow from genetically modified (GM) crops to wild relatives has traditionally emphasized recipients yielding most hybrids. For GM rapeseed ( Brassica napus ), interest has centred on the ‘frequently hybridizing’ Brassica rapa over relatives such as Brassica oleracea , where spontaneous hybrids are unreported in the wild. In two sites, where rapeseed and wild B. oleracea grow together, we used flow cytometry and crop-specific microsatellite markers to identify one triploid F 1 hybrid, together with nine diploid and two near triploid introgressants. Given the newly discovered capacity for spontaneous introgression into B. oleracea , we then surveyed associated flora and fauna to evaluate the capacity of both recipients to harm cohabitant species with acknowledged conservational importance. Only B. oleracea occupies rich communities containing species afforded legislative protection; these include one rare micromoth species that feeds on B. oleracea and warrants further assessment. We conclude that increased attention should now focus on B. oleracea and similar species that yield few crop-hybrids, but possess scope to affect rare or endangered associates.

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Characterization of the Blunt Leaf Apex (bla) Trait in Cucumber

HortScience ◽

10.21273/hortsci.30.7.1461 ◽

1995 ◽

Vol 30 (7) ◽

pp. 1461-1462

Author(s):

Stan C. Hokanson ◽

James F. Hancock ◽

Rebecca Grumet

Keyword(s):

Field Study ◽

Cucumis Sativus ◽

Segregation Analysis ◽

Single Locus ◽

Wild Type ◽

Leaf Base ◽

Leaf Apex ◽

Leaf Phenotype ◽

In The Wild

A further characterization of the cucumber (Cucumis sativus L.) mutant `Wisconsin SMR-18' bla (blunt leaf apex) revealed a new character associated with the previously described leaf phenotype. The attachment of the blade to the petiole of bla plants is flat across, as opposed to the cordate or indented attachment in the wild-type `Wisconsin SMR-18' plants. The new character (truncate leaf base) was easier to score and becomes distinctive earlier in development than previously described leaf apex characters. It was expressed consistently in homozygous bla plants. Segregation analysis of 1159 F2 seedlings arising from self-pollinated `Wisconsin SMR-18' × `Wisconsin SMR-18' bla F1 plants suggested that the leaf base and leaf apex character were controlled by a single locus or two tightly linked ones with a maximum distance between the two of 0.03 cM. In a field study of growth and fitness characteristics, the two genotypes did not differ significantly for flower or fruit count. The similar flowering and fruiting characteristics, along with the reliable early occurring truncate character, likely will make the two genotypes useful for pollination and gene movement studies.

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