| 1. |
- Anderson, Cynthia M., et al.
(författare)
-
Permanent Genetic Resources added to Molecular Ecology Resources Database 1 December 2009-31 January 2010
- 2010
-
Ingår i: Molecular Ecology Resources. - : Wiley. - 1755-098X .- 1755-0998. ; 10:3, s. 576-579
-
Tidskriftsartikel (refereegranskat)abstract
- This article documents the addition of 220 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Allanblackia floribunda, Amblyraja radiata, Bactrocera cucurbitae, Brachycaudus helichrysi, Calopogonium mucunoides, Dissodactylus primitivus, Elodea canadensis, Ephydatia fluviatilis, Galapaganus howdenae howdenae, Hoplostethus atlanticus, Ischnura elegans, Larimichthys polyactis, Opheodrys vernalis, Pelteobagrus fulvidraco, Phragmidium violaceum, Pistacia vera, and Thunnus thynnus. These loci were cross-tested on the following species: Allanblackia gabonensis, Allanblackia stanerana, Neoceratitis cyanescens, Dacus ciliatus, Dacus demmerezi, Bactrocera zonata, Ceratitis capitata, Ceratitis rosa, Ceratits catoirii, Dacus punctatifrons, Ephydatia mulleri, Spongilla lacustris, Geodia cydonium, Axinella sp., Ischnura graellsii, Ischnura ramburii, Ischnura pumilio, Pistacia integerrima and Pistacia terebinthus.
|
|
| 2. |
- Sanchez Guillen, Rosa, et al.
(författare)
-
Genetic divergence predicts reproductive isolation in damselflies
- 2014
-
Ingår i: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 27:1, s. 76-87
-
Tidskriftsartikel (refereegranskat)abstract
- Reproductive isolation is the defining characteristic of a biological species, and a common, but often untested prediction is a positive correlation between reproductive isolation and genetic divergence. Here, we test for this correlation in odonates, an order characterized by strong sexual selection. First, we measure reproductive isolation and genetic divergence in eight damselfly genera (30 species pairs) and test for a positive correlation. Second, we estimate the genetic threshold preventing hybrid formation and empirically test this threshold using wild populations of species within the Ischnura genus. Our results indicate a positive and strong correlation between reproductive isolation and genetic distance using both mitochondrial and nuclear genes cytochrome oxidase II (COII: r=0.781 and 18S-28S: r=0.658). Hybridization thresholds range from -0.43 to 1.78% for COII and -0.052-0.71% for 18S-28S, and both F-1-hybrids and backcrosses were detected in wild populations of two pairs of Ischnura species with overlapping thresholds. Our study suggests that threshold values are suitable to identify species prone to hybridization and that positive isolation-divergence relationships are taxonomically widespread.
|
|
| 3. |
- Sanchez Guillen, Rosa, et al.
(författare)
-
Introgression and rapid species turnover in sympatric damselflies
- 2011
-
Ingår i: BMC Evolutionary Biology. - : Springer Science and Business Media LLC. - 1471-2148. ; 11:article no 210
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Studying contemporary hybridization increases our understanding of introgression, adaptation and, ultimately, speciation. The sister species Ischnura elegans and I. graellsii (Odonata: Coenagrionidae) are ecologically, morphologically and genetically similar and hybridize. Recently, I. elegans has colonized northern Spain, creating a broad sympatric region with I. graellsii. Here, we review the distribution of both species in Iberia and evaluate the degree of introgression of I. graellsii into I. elegans using six microsatellite markers (442 individuals from 26 populations) and five mitochondrial genes in sympatric and allopatric localities. Furthermore, we quantify the effect of hybridization on the frequencies of the genetically controlled colour polymorphism in females of both species. Results: In a principal component analysis of the microsatellite data, the first two principal components summarised almost half (41%) of the total genetic variation. The first axis revealed a clear separation of I. graellsii and I. elegans populations, while the second axis separated I. elegans populations. Admixture analyses showed extensive hybridization and introgression in I. elegans populations, consistent with I. elegans backcrosses and occasional F-1-hybrids, suggesting hybridization is on-going. More specifically, approximately 58% of the 166 Spanish I. elegans individuals were assigned to the I. elegans backcross category, whereas not a single of those individuals was assigned to the backcross with I. graellsii. The mitochondrial genes held little genetic variation, and the most common haplotype was shared by the two species. Conclusions: The results suggest rapid species turnover in sympatric regions in favour of I. elegans, corroborating previous findings that I. graellsii suffers a mating disadvantage in sympatry with I. elegans. Examination of morph frequency dynamics indicates that hybridization is likely to have important implications for the maintenance of multiple female morphs, in particular during the initial period of hybridization.
|
|
| 4. |
- Sanchez Guillen, Rosa, et al.
(författare)
-
Ontogenetic shifts in male mating preference and morph-specific polyandry in a female colour polymorphic insect
- 2013
-
Ingår i: BMC Evolutionary Biology. - : Springer Science and Business Media LLC. - 1471-2148. ; 13
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Sexual conflict over mating rates may favour the origin and maintenance of phenotypes with contrasting reproductive strategies. The damselfly Ischnura elegans is characterised by a female colour polymorphism that consists of one androchrome and two gynochrome female morphs. Previous studies have shown that the polymorphism is genetic and to a high extent maintained by negative frequency-dependent mating success that varies temporally and spatially. However, the role of learning in male mating preferences has received little attention. We used molecular markers to investigate differences in polyandry between female morphs. In addition, we experimentally investigated innate male mating preferences and experience-dependent shifts in male mating preferences for female morphs. Results: Field and molecular data show that androchrome females were less polyandrous than gynochrome females. Interestingly, we found that naive males showed significantly higher sexual preferences to androchrome than to gynochrome females in experimental trials. In contrast, experienced males showed no preference for androchrome females. Conclusions: The ontogenetic change in male mate preferences occurs most likely because of learned mate recognition after experience with females, which in this case does not result in a preference for one of the morphs, but rather in the loss of an innate preference for androchrome females.
|
|
| 5. |
- Sanchez Guillen, Rosa, et al.
(författare)
-
Rapid evolution of prezygotic barriers in non-territorial damselflies
- 2014
-
Ingår i: Biological Journal of the Linnean Society. - : Oxford University Press (OUP). - 0024-4066. ; 113:2, s. 485-496
-
Tidskriftsartikel (refereegranskat)abstract
- A central question in evolutionary biology concerns the accumulation of reproductive barriers during speciation. However, separating the reproductive barriers that have led to speciation from those that have secondarily accumulated (i.e. after initial divergence) is a widely recognized problem. Ideal candidate species for overcoming this problem are young species, where time for additional barriers to accrue has been limited. In the present study, we add to previous studies investigating the strength of reproductive barriers between the parapatric damselflies Ischnura elegans and Ischnura graellsii by quantifying seven prezygotic barriers between the allopatric pairs of I.elegans and Ischnura genei, as well as I.graellsii and I.genei. Specifically, we measured four premating (temporal, sexual, mechanical (I), and mechanical (II)) and three postmating (oviposition success, fecundity, and fertility) barriers using experimental approaches and, for first time, we investigated the mechanisms causing mechanical isolation, which is the strongest reproductive barrier in ischnurans. The findings of the present study support the notion that premating barriers are generally strong and contribute significantly to total reproductive isolation in young lineages (65-98%), although they never solely lead to complete isolation. Asymmetry was generally stronger in premating than in postmating barriers, and was driven mostly through asymmetry in mechanical isolation, which is caused by morphological divergence of secondary sexual appendages. We found that barriers act multiplicatively in all species combinations tested, with the exception of sexual isolation, which was not detected. Our results are consistent with a recent allopatric speciation scenario driven by differences in male anal appendages, either impeding copulation or affecting female preferences. Taken together, the results from this and previous studies in diverse odonate genera suggest that premating barriers have evolved rapidly in ischnuran damselflies and, although reproductive isolation in ischnurans is more commonly the result of several barriers acting together, morphological divergence of secondary sexual appendages appears to be a common factor facilitating premating isolation in this group.(c) 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113, 485-496.
|
|
| 6. |
- Sanchez Guillen, Rosa, et al.
(författare)
-
Strong asymmetry in the relative strengths of prezygotic and postzygotic barriers between two damselfly sister species
- 2012
-
Ingår i: Evolution. - : Wiley. - 1558-5646 .- 0014-3820. ; 66:3, s. 690-707
-
Tidskriftsartikel (refereegranskat)abstract
- One of the longest debates in biology has been over the relative importance of different isolating barriers in speciation. However, for most species, there are few data evaluating their relative contributions and we can only speculate on the general roles of pre- and postzygotic isolation. Here, we quantify the absolute and cumulative contribution of 19 potential reproductive barriers between two sympatric damselfly sister species, Ischnura elegans and I. graellsii, including both premating (habitat, temporal, sexual and mechanical isolation) and postmating barriers (prezygotic: sperm insemination success and removal rate, oviposition success, fertility, fecundity; postzygotic: hybrid viability, hybrid sterility and hybrid breakdown). In sympatry, total reproductive isolation between I. elegans females and I. graellsii males was 95.2%, owing mostly to a premating mechanical incompatibility (93.4%), whereas other barriers were of little importance. Isolation between I. graellsii females and I. elegans males was also nearly complete (95.8%), which was caused by the cumulative action of multiple prezygotic (n= 4, 75.4%) and postzygotic postmating barriers (n= 5, 7.4%). Our results suggest that premating barriers are key factors in preventing gene flow between species, and that the relative strengths of premating barriers is highly asymmetrical between the reciprocal crosses.
|
|
| 7. |
- Sanchez Guillen, Rosa, et al.
(författare)
-
The influence of stochastic and selective forces in the population divergence of female colour polymorphism in damselflies of the genus Ischnura
- 2011
-
Ingår i: Heredity. - : Springer Science and Business Media LLC. - 1365-2540 .- 0018-067X. ; 107:6, s. 513-522
-
Tidskriftsartikel (refereegranskat)abstract
- Disentangling the relative importance and potential interactions of selection and genetic drift in driving phenotypic divergence of species is a classical research topic in population genetics and evolutionary biology. Here, we evaluate the role of stochastic and selective forces on population divergence of a colour polymorphism in seven damselfly species of the genus Ischnura, with a particular focus on I. elegans and I. graellsii. Colour-morph frequencies in Spanish I. elegans populations varied greatly, even at a local scale, whereas more similar frequencies were found among populations in eastern Europe. In contrast, I. graellsii and the other five Ischnura species showed little variation in colour-morph frequencies between populations. FST-outlier analyses revealed that the colour locus deviated strongly from neutral expectations in Spanish populations of I. elegans, contrasting the pattern found in eastern European populations, and in I. graellsii, where no such discrepancy between morph divergence and neutral divergence could be detected. This suggests that divergent selection has been operating on the colour locus in Spanish populations of I. elegans, whereas processes such as genetic drift, possibly in combination with other forms of selection (such as negative frequency-dependent selection), appear to have been present in other regions, such as eastern Europe. Overall, the results indicate that both selective and stochastic processes operate on these colour polymorphisms, and suggest that the relative importance of factors varies between geographical regions.
|
|
| 8. |
- Wellenreuther, Maren, et al.
(författare)
-
Development of 12 polymorphic microsatellite loci in Ischnura elegans (Odonata: Coenagrionidae)
- 2010
-
Ingår i: Molecular Ecology Resources. - 1755-098X. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- We isolated and characterised 12 polymorphic microsatellite loci for the blue-tailed damselfly Ischnura elegans by screening a genomic library enriched for microsatellite motifs. The loci showed high variability for the number of alleles, and the expected and observed heterozygosities, and thus will be useful for future molecular studies. Cross-amplification in I. graellsii, I. ramburii and I. pumilio showed that the majority of the microsatellites also produced polymorphic products in these species.
|
|
| 9. |
- Wellenreuther, Maren, et al.
(författare)
-
Environmental and climatic determinants of molecular diversity and genetic population structure in a coenagrionid damselfly.
- 2011
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:5
-
Tidskriftsartikel (refereegranskat)abstract
- Identifying environmental factors that structure intraspecific genetic diversity is of interest for both habitat preservation and biodiversity conservation. Recent advances in statistical and geographical genetics make it possible to investigate how environmental factors affect geographic organisation and population structure of molecular genetic diversity within species. Here we present a study on a common and wide ranging insect, the blue tailed damselfly Ischnuraelegans, which has been the target of many ecological and evolutionary studies. We addressed the following questions: (i) Is the population structure affected by longitudinal or latitudinal gradients?; (ii) Do geographic boundaries limit gene flow?; (iii) Does geographic distance affect connectivity and is there a signature of past bottlenecks?; (iv) Is there evidence of a recent range expansion and (vi) what is the effect of geography and climatic factors on population structure? We found low to moderate genetic sub-structuring between populations (mean F(ST) = 0.06, D(est) = 0.12), and an effect of longitude, but not latitude, on genetic diversity. No significant effects of geographic boundaries (e.g. water bodies) were found. F(ST)-and D(est)-values increased with geographic distance; however, there was no evidence for recent bottlenecks. Finally, we did not detect any molecular signatures of range expansions or an effect of geographic suitability, although local precipitation had a strong effect on genetic differentiation. The population structure of this small insect has probably been shaped by ecological factors that are correlated with longitudinal gradients, geographic distances, and local precipitation. The relatively weak global population structure and high degree of genetic variation within populations suggest that I. elegans has high dispersal ability, which is consistent with this species being an effective and early coloniser of new habitats.
|
|
| 10. |
|
|
