Bicyclus anynana

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Paul M. Brakefield - One of the best experts on this subject based on the ideXlab platform.

  • differentiation in putative male sex pheromone components across and within populations of the african butterfly Bicyclus anynana as a potential driver of reproductive isolation
    Ecology and Evolution, 2016
    Co-Authors: Paul Bacquet, Paul M. Brakefield, Honglei Wang, Christer Lofstedt, Oskar Brattstrom, Maaike A De Jong, Freerk Molleman, Stephanie Heuskin, George Lognay, Alain Vanderpoorten
    Abstract:

    Sexual traits are often the most divergent characters among closely related species, suggesting an important role of sexual traits in speciation. However, to prove this, we need to show that sexual trait differences accumulate before or during the speciation process, rather than being a consequence of it. Here, we contrast patterns of divergence among putative male sex pheromone (pMSP) composition and the genetic structure inferred from variation in the mitochondrial cytochrome oxidase 1 and nuclear CAD loci in the African butterfly Bicyclus anynana (Butler, 1879) to determine whether the evolution of “pheromonal dialects” occurs before or after the differentiation process. We observed differences in abundance of some shared pMSP components as well as differences in the composition of the pMSP among B. anynana populations. In addition, B. anynana individuals from Kenya displayed differences in the pMSP composition within a single population that appeared not associated with genetic differences. These differences in pMSP composition both between and within B. anynana populations were as large as those found between different Bicyclus species. Our results suggest that “pheromonal dialects” evolved within and among populations of B. anynana and may therefore act as precursors of an ongoing speciation process.

  • the predictive adaptive response modeling the life history evolution of the butterfly Bicyclus anynana in seasonal environments
    The American Naturalist, 2013
    Co-Authors: Joost Van Den Heuvel, Bas J. Zwaan, Paul M. Brakefield, Marjo Saastamoinen, Thomas B L Kirkwood, Daryl P Shanley
    Abstract:

    Abstract A predictive adaptive response (PAR) is a type of developmental plasticity where the response to an environmental cue is not immediately advantageous but instead is later in life. The PAR is a way for organisms to maximize fitness in varying environments. Insects living in seasonal environments are valuable model systems for testing the existence and form of PAR. Previous manipulations of the larval and the adult environments of the butterfly Bicyclus anynana have shown that individuals that were food restricted during the larval stage coped better with forced flight during the adult stage compared to those with optimal conditions in the larval stage. Here, we describe a state-dependent energy allocation model, which we use to test whether such a response to food restriction could be adaptive in nature where this butterfly exhibits seasonal cycles. The results from the model confirm the responses obtained in our previous experimental work and show how such an outcome was facilitated by resource a...

  • The predictive adaptive response: modeling the life-history evolution of the butterfly Bicyclus anynana in seasonal environments.
    The American Naturalist, 2013
    Co-Authors: Joost Van Den Heuvel, Bas J. Zwaan, Paul M. Brakefield, Marjo Saastamoinen, Thomas B L Kirkwood, Daryl P Shanley
    Abstract:

    A predictive adaptive response (PAR) is a type of developmental plasticity where the response to an environmental cue is not immediately advantageous but instead is later in life. The PAR is a way for organisms to maximize fitness in varying environments. Insects living in seasonal environments are valuable model systems for testing the existence and form of PAR. Previous manipulations of the larval and the adult environments of the butterfly Bicyclus anynana have shown that individuals that were food restricted during the larval stage coped better with forced flight during the adult stage compared to those with optimal conditions in the larval stage. Here, we describe a state-dependent energy allocation model, which we use to test whether such a response to food restriction could be adaptive in nature where this butterfly exhibits seasonal cycles. The results from the model confirm the responses obtained in our previous experimental work and show how such an outcome was facilitated by resource allocation patterns to the thorax during the pupal stage. We conclude that for B. anynana, early-stage cues can direct development toward a better adapted phenotype later in life and, therefore, that a PAR has evolved in this species.

  • footprints of selection in wild populations of Bicyclus anynana along a latitudinal cline
    Molecular Ecology, 2013
    Co-Authors: Bas J. Zwaan, Paul M. Brakefield, Patricia Beldade, M A De Jong, S Collins
    Abstract:

    One of the major questions in ecology and evolutionary biology is how variation in the genome enables species to adapt to divergent environments. Here, we study footprints of thermal selection in candidate genes in six wild populations of the afrotropical butterfly Bicyclus anynana sampled along a c. 3000 km latitudinal cline. We sequenced coding regions of 31 selected genes with known functions in metabolism, pigment production, development and heat shock responses. These include genes for which we expect a priori a role in thermal adaptation and, thus, varying selection pressures along a latitudinal cline, and genes we do not expect to vary clinally and can be used as controls. We identified amino acid substitution polymorphisms in 13 genes and tested these for clinal variation by correlation analysis of allele frequencies with latitude. In addition, we used two FST-based outlier methods to identify loci with higher population differentiation than expected under neutral evolution, while accounting for potentially confounding effects of population structure and demographic history. Two metabolic enzymes of the glycolytic pathway, UGP and Treh, showed clinal variation. The same loci showed elevated population differentiation and were identified as significant outliers. We found no evidence of clines in the pigmentation genes, heat shock proteins and developmental genes. However, we identified outlier loci in more localized parts of the range in the pigmentation genes yellow and black. We discuss that the observed clinal variation and elevated population divergence in UGP and Treh may reflect adaptation to a geographic thermal gradient.

  • environmentally induced dispersal related life history syndrome in the tropical butterfly Bicyclus anynana
    Journal of Evolutionary Biology, 2012
    Co-Authors: Paul M. Brakefield, Marjo Saastamoinen, Otso Ovaskainen
    Abstract:

    Dispersal is a key process for understanding the persistence of populations as well as the capacity of organisms to respond to environmental change. Therefore, understanding factors that may facilitate or constrain the evolution of dispersal is of crucial interest. Assessments of phenotypic variation in various behavioural, physiological and morphological traits related to insect dispersal and flight performance are common, yet very little is known about the genetic associations among these traits. We have used experiments on the butterfly Bicyclus anynana to estimate genetic variation and covariation in seven behavioural, physiological and morphological traits related to flight potential and hence dispersal. Our goal was to characterize the heritabilities and genetic correlations among these traits and thus to understand more about the evolution of dispersal-related life-history syndromes in butterflies. Using a version of the animal model, we showed that all of the traits varied between the sexes, and most were either positively or negatively (phenotypically and/or genetically) correlated with body size. Heritable variation was present in most traits, with the highest heritabilities estimated for body mass and thorax ratio. The variance in flight activity among multiple measurements for the same individual was high even after controlling for the prevailing environmental conditions, indicating the importance of behavioural switching and/or inherent randomness associated with this type of movement. A number of dispersal-related traits showed phenotypic correlations among one another, but only a few of these were associated with significant genetic correlations indicating that covariances between these traits in Bicyclus anynana are mainly environmentally induced.

Antonia Monteiro - One of the best experts on this subject based on the ideXlab platform.

  • multiple loci control eyespot number variation on the hindwings of Bicyclus anynana butterflies
    Genetics, 2020
    Co-Authors: Antonia Monteiro, Angel G Riveracolon, Erica L Westerman, Steven M Van Belleghem, Riccardo Papa
    Abstract:

    The underlying genetic changes that regulate the appearance and disappearance of repeated traits, or serial homologs, remain poorly understood. One hypothesis is that variation in genomic regions flanking master regulatory genes, also known as input–output genes, controls variation in trait number, making the locus of evolution almost predictable. Another hypothesis implicates genetic variation in up- or downstream loci of master control genes. Here, we use the butterfly Bicyclus anynana, a species that exhibits natural variation in eyespot number on the dorsal hindwing, to test these two hypotheses. We first estimated the heritability of dorsal hindwing eyespot number by breeding multiple butterfly families differing in eyespot number and regressing eyespot numbers of offspring on midparent values. We then estimated the number and identity of independent genetic loci contributing to eyespot number variation by performing a genome-wide association study with restriction site-associated DNA sequencing from multiple individuals varying in number of eyespots sampled across a freely breeding laboratory population. We found that dorsal hindwing eyespot number has a moderately high heritability of ∼0.50 and is characterized by a polygenic architecture. Previously identified genomic regions involved in eyespot development, and novel ones, display high association with dorsal hindwing eyespot number, suggesting that homolog number variation is likely determined by regulatory changes at multiple loci that build the trait, and not by variation at single master regulators or input–output genes.

  • dissection of larval and pupal wings of Bicyclus anynana butterflies
    Methods and protocols, 2020
    Co-Authors: Tirtha Das Banerjee, Antonia Monteiro
    Abstract:

    The colorful wings of butterflies are emerging as model systems for evolutionary and developmental studies. Some of these studies focus on localizing gene transcripts and proteins in wings at the larval and pupal stages using techniques such as immunostaining and in situ hybridization. Other studies quantify mRNA expression levels or identify regions of open chromatin that are bound by proteins at different stages of wing development. All these techniques require dissection of the wings from the animal but a detailed video protocol describing this procedure has not been available until now. Here, we present a written and accompanying video protocol where we describe the tools and the method we use to remove the larval and pupal wings of the African Squinting Bush Brown butterfly Bicyclus anynana. This protocol should be easy to adapt to other species.

  • Early-exposure to new sex pheromone blends alters mate preference in female butterflies and in their offspring.
    Nature Communications, 2020
    Co-Authors: Emilie Dion, Katie Weber, Antonia Monteiro
    Abstract:

    While the diversity of sex pheromone communication systems across insects is well documented, the mechanisms that lead to such diversity are not well understood. Sex pheromones constitute a species-specific system of sexual communication that reinforces interspecific reproductive isolation. When odor blends evolve, the efficacy of male-female communication becomes compromised, unless preference for novel blends also evolves. We explore odor learning as a possible mechanism leading to changes in sex pheromone preferences in the butterfly Bicyclus anynana. Our experiments reveal mating patterns suggesting that mating bias for new blends can develop following a short learning experience, and that this maternal experience impacts the mating outcome of offspring without further exposure. We propose that odor learning can be a key factor in the evolution of sex pheromone blend recognition and in chemosensory speciation. Pheromones are an essential cue for species recognition and mate selection in many insects including the butterfly Bicyclus anynana. Here the authors show that females with a short social experience of a new male learn preferences for novel pheromone blends, a preference which also occurs in their daughters.

  • interacting effects of eyespot number and ultraviolet reflectivity on predation risk in Bicyclus anynana lepidoptera nymphalidae
    Journal of Insect Science, 2019
    Co-Authors: Ian Z W Chan, Antonia Monteiro, Fathima Zohara Rafi
    Abstract:

    : Small marginal eyespots on lepidopteran wings are conspicuous elements that attract a predator's attention to deflect attacks away from the body, but the role of ultraviolet (UV) reflectivity at the center of these patterns and variation in eyespot number in altering the function of eyespots remains unclear. Here, we performed a field-based predation experiment with artificial prey items based on the appearance of squinting bush brown butterflies Bicyclus anynana (Butler, 1879). We tested how two visual properties of the wing pattern affect predation risk: i) the number of eyespots on the ventral forewing surface-two or four; and ii) the UV reflectivity of eyespot centers-normal (where the UV reflectivity of the centers contrasts strongly with that of the darker surrounding ring) or blocked (where this contrast is reduced). In total, 807 prey items were deployed at two sites. We found a significant interaction between the number of ventral forewing eyespots and UV reflectivity in the eyespot centers: in items with fewer eyespots, blocking UV resulted in increased predation risk whereas in items with more eyespots, blocking UV resulted in decreased predation risk. If higher predation of paper models can be equated with higher levels of wing margin/eyespot conspicuity, these results demonstrate that UV reflectivity is an important factor in making eyespots more conspicuous to predators and suggest that the fitness of particular butterfly eyespot number variants may depend on the presence or absence of UV in their centers and on the ability of local predator guilds to detect UV.

  • hox genes are essential for the development of novel serial homologous eyespots on the wings of Bicyclus anynana butterflies
    bioRxiv, 2019
    Co-Authors: Yuji Matsuoka, Antonia Monteiro
    Abstract:

    Abstract The eyespot patterns found on the wings of nymphalid butterflies are novel serial homologous traits that originated first in hindwings and subsequently in forewings, suggesting that eyespot development might be dependent on Hox genes. Hindwings differ from forewings in the expression of Ultrabithorax (Ubx), but the function of this Hox gene in eyespot development as well as that of another Hox gene Antennapedia (Antp), expressed specifically in eyespots centers on both wings, are still unclear. We used CRISPR-Cas9 to target both genes in Bicyclus anynana butterflies. We show that Antp is essential for eyespot development on the forewings and for the differentiation of white centers and larger eyespots on hindwings, whereas Ubx is essential for the development of at least some hindwing eyespots but also for repressing the size of other eyespots. Additionally, Antp is essential for the development of silver scales in male wings. In summary, Antp and Ubx, in addition to their conserved roles in modifying serial homologous traits along the anterior-posterior axis of animals, have acquired a novel role in promoting the development of a new set of serial homologs, the eyespot patterns, in both forewings (Antp) and hindwings (Antp and Ubx) of B. anynana butterflies. We propose that the peculiar pattern of eyespot origins on hindwings first, followed by forewings, could be due to an initial co-option of Ubx into eyespot development, followed by a later, partially redundant co-option of Antp into the same network.

Bas J. Zwaan - One of the best experts on this subject based on the ideXlab platform.

  • a high coverage draft genome of the mycalesine butterfly Bicyclus anynana
    GigaScience, 2017
    Co-Authors: Reuben W Nowell, Bas J. Zwaan, Benjamin Elsworth, Vicencio Oostra, Christopher W Wheat, Marjo Saastamoinen, Ilik J Saccheri, Bethany R Wasik, Heidi Connahs, Muhammad L Aslam
    Abstract:

    The mycalesine butterfly Bicyclus anynana, the “Squinting bush brown,” is a model organism in the study of lepidopteran ecology, development, and evolution. Here, we present a draft genome sequence for B. anynana to serve as a genomics resource for current and future studies of this important model species. Seven libraries with insert sizes ranging from 350 bp to 20 kb were constructed using DNA from an inbred female and sequenced using both Illumina and PacBio technology; 128 Gb of raw Illumina data was filtered to 124 Gb and assembled to a final size of 475 Mb (∼×260 assembly coverage). Contigs were scaffolded using mate-pair, transcriptome, and PacBio data into 10 800 sequences with an N50 of 638 kb (longest scaffold 5 Mb). The genome is comprised of 26% repetitive elements and encodes a total of 22 642 predicted protein-coding genes. Recovery of a BUSCO set of core metazoan genes was almost complete (98%). Overall, these metrics compare well with other recently published lepidopteran genomes. We report a high-quality draft genome sequence for Bicyclus anynana. The genome assembly and annotated gene models are available at LepBase (http://ensembl.lepbase.org/index.html).

  • The predictive adaptive response: modeling the life-history evolution of the butterfly Bicyclus anynana in seasonal environments.
    The American Naturalist, 2013
    Co-Authors: Joost Van Den Heuvel, Bas J. Zwaan, Paul M. Brakefield, Marjo Saastamoinen, Thomas B L Kirkwood, Daryl P Shanley
    Abstract:

    A predictive adaptive response (PAR) is a type of developmental plasticity where the response to an environmental cue is not immediately advantageous but instead is later in life. The PAR is a way for organisms to maximize fitness in varying environments. Insects living in seasonal environments are valuable model systems for testing the existence and form of PAR. Previous manipulations of the larval and the adult environments of the butterfly Bicyclus anynana have shown that individuals that were food restricted during the larval stage coped better with forced flight during the adult stage compared to those with optimal conditions in the larval stage. Here, we describe a state-dependent energy allocation model, which we use to test whether such a response to food restriction could be adaptive in nature where this butterfly exhibits seasonal cycles. The results from the model confirm the responses obtained in our previous experimental work and show how such an outcome was facilitated by resource allocation patterns to the thorax during the pupal stage. We conclude that for B. anynana, early-stage cues can direct development toward a better adapted phenotype later in life and, therefore, that a PAR has evolved in this species.

  • the predictive adaptive response modeling the life history evolution of the butterfly Bicyclus anynana in seasonal environments
    The American Naturalist, 2013
    Co-Authors: Joost Van Den Heuvel, Bas J. Zwaan, Paul M. Brakefield, Marjo Saastamoinen, Thomas B L Kirkwood, Daryl P Shanley
    Abstract:

    Abstract A predictive adaptive response (PAR) is a type of developmental plasticity where the response to an environmental cue is not immediately advantageous but instead is later in life. The PAR is a way for organisms to maximize fitness in varying environments. Insects living in seasonal environments are valuable model systems for testing the existence and form of PAR. Previous manipulations of the larval and the adult environments of the butterfly Bicyclus anynana have shown that individuals that were food restricted during the larval stage coped better with forced flight during the adult stage compared to those with optimal conditions in the larval stage. Here, we describe a state-dependent energy allocation model, which we use to test whether such a response to food restriction could be adaptive in nature where this butterfly exhibits seasonal cycles. The results from the model confirm the responses obtained in our previous experimental work and show how such an outcome was facilitated by resource a...

  • footprints of selection in wild populations of Bicyclus anynana along a latitudinal cline
    Molecular Ecology, 2013
    Co-Authors: Bas J. Zwaan, Paul M. Brakefield, Patricia Beldade, M A De Jong, S Collins
    Abstract:

    One of the major questions in ecology and evolutionary biology is how variation in the genome enables species to adapt to divergent environments. Here, we study footprints of thermal selection in candidate genes in six wild populations of the afrotropical butterfly Bicyclus anynana sampled along a c. 3000 km latitudinal cline. We sequenced coding regions of 31 selected genes with known functions in metabolism, pigment production, development and heat shock responses. These include genes for which we expect a priori a role in thermal adaptation and, thus, varying selection pressures along a latitudinal cline, and genes we do not expect to vary clinally and can be used as controls. We identified amino acid substitution polymorphisms in 13 genes and tested these for clinal variation by correlation analysis of allele frequencies with latitude. In addition, we used two FST-based outlier methods to identify loci with higher population differentiation than expected under neutral evolution, while accounting for potentially confounding effects of population structure and demographic history. Two metabolic enzymes of the glycolytic pathway, UGP and Treh, showed clinal variation. The same loci showed elevated population differentiation and were identified as significant outliers. We found no evidence of clines in the pigmentation genes, heat shock proteins and developmental genes. However, we identified outlier loci in more localized parts of the range in the pigmentation genes yellow and black. We discuss that the observed clinal variation and elevated population divergence in UGP and Treh may reflect adaptation to a geographic thermal gradient.

  • mitochondrial dna signature for range wide populations of Bicyclus anynana suggests a rapid expansion from recent refugia
    PLOS ONE, 2011
    Co-Authors: Bas J. Zwaan, Paul M. Brakefield, Maaike A De Jong, Niklas Wahlberg, Marleen Van Eijk
    Abstract:

    This study investigates the genetic diversity, population structure and demographic history of the afrotropical butterfly Bicyclus anynana using mitochondrial DNA (mtDNA). Samples from six wild populations covering most of the species range from Uganda to South Africa were compared for the cytochrome c oxidase subunit gene (COI). Molecular diversity indices show overall high mtDNA diversity for the populations, but low nucleotide divergence between haplotypes. Our results indicate relatively little geographic population structure among the southern populations, especially given the extensive distributional range and an expectation of limited gene flow between populations. We implemented neutrality tests to assess signatures of recent historical demographic events. Tajima's D test and Fu's FS test both suggested recent population growth for the populations. The results were only significant for the southernmost populations when applying Tajima's D, but Fu's FS indicated significant deviations from neutrality for all populations except the one closest to the equator. Based on our own findings and those from pollen and vegetation studies, we hypothesize that the species range of B. anynana was reduced to equatorial refugia during the last glacial period, and that the species expanded southwards during the past 10.000 years. These results provide crucial background information for studies of phenotypic and molecular adaptation in wild populations of B. anynana.

Klaus Fischer - One of the best experts on this subject based on the ideXlab platform.

  • interactive effects of acclimation temperature and short term stress exposure on resistance traits in the butterfly Bicyclus anynana
    Physiological Entomology, 2014
    Co-Authors: Isabell Karl, Marlen Becker, Tjorven Hinzke, Melanie Mielke, Maria Schiffler, Klaus Fischer
    Abstract:

    The ability to buffer detrimental effects of environmental stress on fitness is of great ecological importance because, in nature, pronounced environmental variation may regularly induce stress. Furthermore, several stressors may interact in a synergistic manner. In the present study, plastic responses in cold, heat and starvation resistance are investigated in the tropical butterfly Bicyclus anynana Butler, 1879, using a full factorial design with two acclimation temperatures (20 and 27 °C) and four short-term stress treatments (control, cold, heat, starvation). Warm-acclimated butterflies are more heat- but less cold-tolerant as expected. Short-term cold and starvation exposure reduce cold and heat resistance, and short-term heat exposure decreases cold but increases heat resistance. Starvation resistance is not affected by any of the short-term treatments. Thus, the effects of short-term stress exposure are either neutral or negative, except for a positive effect of heat exposure on heat resistance, indicating the negative effects of pre-exposure to stress. Interestingly, significant interactions between acclimation temperature and short-term stress exposure for heat and cold resistance are found, demonstrating that larger temperature differences incur more damage. Therefore, animals may not generally be able to benefit from pre-exposure to stress (through ‘hardening’), depending on their previously experienced conditions. The complex interactions between environmental variation, stress and resistance are highlighted, warranting further investigations.

  • Interactive effects of acclimation temperature and short‐term stress exposure on resistance traits in the butterfly Bicyclus anynana
    Physiological Entomology, 2014
    Co-Authors: Isabell Karl, Marlen Becker, Tjorven Hinzke, Melanie Mielke, Maria Schiffler, Klaus Fischer
    Abstract:

    The ability to buffer detrimental effects of environmental stress on fitness is of great ecological importance because, in nature, pronounced environmental variation may regularly induce stress. Furthermore, several stressors may interact in a synergistic manner. In the present study, plastic responses in cold, heat and starvation resistance are investigated in the tropical butterfly Bicyclus anynana Butler, 1879, using a full factorial design with two acclimation temperatures (20 and 27 °C) and four short-term stress treatments (control, cold, heat, starvation). Warm-acclimated butterflies are more heat- but less cold-tolerant as expected. Short-term cold and starvation exposure reduce cold and heat resistance, and short-term heat exposure decreases cold but increases heat resistance. Starvation resistance is not affected by any of the short-term treatments. Thus, the effects of short-term stress exposure are either neutral or negative, except for a positive effect of heat exposure on heat resistance, indicating the negative effects of pre-exposure to stress. Interestingly, significant interactions between acclimation temperature and short-term stress exposure for heat and cold resistance are found, demonstrating that larger temperature differences incur more damage. Therefore, animals may not generally be able to benefit from pre-exposure to stress (through ‘hardening’), depending on their previously experienced conditions. The complex interactions between environmental variation, stress and resistance are highlighted, warranting further investigations.

  • fitness costs associated with different frequencies and magnitudes of temperature change in the butterfly Bicyclus anynana
    Journal of Thermal Biology, 2014
    Co-Authors: Kristin Franke, Nadja Heitmann, Anne Tobner, Klaus Fischer
    Abstract:

    Abstract Plastic responses to changes in environmental conditions are ubiquitous and typically highly effective, but are predicted to incur costs. We here investigate the effects of different frequencies and magnitudes of temperature change in the tropical butterfly Bicyclus anynana , considering developmental ( Experiment 1 ) and adult stage plasticity ( Experiment 2 ). We predicted negative effects of more frequent temperature changes on development, immune function and/or reproduction. Results from Experiment 1 showed that repeated temperature changes during development, if involving large amplitudes, negatively affect larval time, larval growth rate and pupal mass, while adult traits remained unaffected. However, results from treatment groups with smaller temperature amplitudes yielded no clear patterns. In Experiment 2 prolonged but not repeated exposure to 39 °C increased heat tolerance, potentially reflecting costs of repeatedly activating emergency responses. At the same time fecundity was more strongly reduced in the group with prolonged heat stress, suggesting a trade-off between heat tolerance and reproduction. Clear effects were restricted to conditions involving large temperature amplitudes or high temperatures.

  • Old‐male paternity advantage is a function of accumulating sperm and last‐male precedence in a butterfly
    Molecular Ecology, 2013
    Co-Authors: Tobias Kehl, Isabell Karl, Klaus Fischer
    Abstract:

    Old-male mating advantage has been convincingly demonstrated in Bicyclus anynana butterflies. This intriguing pattern may be explained by two alternative hypotheses: (i) an increased aggressiveness and persistence of older males during courtship, being caused by the older males' low residual reproductive value; and (ii) an active preference of females towards older males what reflects a good genes hypothesis. Against this background, we here investigate postcopulatory sexual selection by double-mating Bicyclus anynana females to older and younger males, thus allowing for sperm competition and cryptic mate choice, and by genotyping the resulting offspring. Virgin females were mated with a younger virgin (2-3 days old) and afterwards an older virgin male (12-13 days old) or vice versa. Older males had a higher paternity success than younger ones, but only when being the second (=last) mating partner, while paternity success was equal among older and younger males when older males were the first mating partner. Older males produced larger spermatophores with much higher numbers of fertile sperm than younger males. Thus, we found no evidence for cryptic female mate choice. Rather, the findings reported here seem to result from a combination of last-male precedence and the number of sperm transferred upon mating, both increasing paternity success.

  • Directional selection on cold tolerance does not constrain plastic capacity in a butterfly.
    BMC Evolutionary Biology, 2012
    Co-Authors: Kristin Franke, Anneke Dierks, Klaus Fischer
    Abstract:

    Background Organisms may respond to environmental change by means of genetic adaptation, phenotypic plasticity or both, which may result in genotype-environment interactions (G x E) if genotypes differ in their phenotypic response. We here specifically target the latter source of variation (i.e. G x E) by comparing plastic responses among lines of the tropical butterfly Bicyclus anynana that had been selected for increased cold tolerance and according controls. Our main aim here was to test the hypothesis that directional selection on cold tolerance will interfere with plastic capacities.

Patricia Beldade - One of the best experts on this subject based on the ideXlab platform.

  • transcriptomics of olfactory communication mediated by male sex pheromone in Bicyclus anynana
    8th international symposium “Eco-evolutionary dynamics” Urban Ecology and Evolution, 2015
    Co-Authors: Caroline Nieberding, Alok Arun, Veronique Baumle, Celine Noirot, Christophe Klopp, Patricia Beldade
    Abstract:

    Transcriptomics of olfactory communication mediated by male sex pheromone in Bicyclus anynana. 8th international symposium “Eco-evolutionary dynamics”, Urban Ecology and Evolution, Antwerp, Belgium, February 4th. Celine Noirot et Christophe klopp

  • footprints of selection in wild populations of Bicyclus anynana along a latitudinal cline
    Molecular Ecology, 2013
    Co-Authors: Bas J. Zwaan, Paul M. Brakefield, Patricia Beldade, M A De Jong, S Collins
    Abstract:

    One of the major questions in ecology and evolutionary biology is how variation in the genome enables species to adapt to divergent environments. Here, we study footprints of thermal selection in candidate genes in six wild populations of the afrotropical butterfly Bicyclus anynana sampled along a c. 3000 km latitudinal cline. We sequenced coding regions of 31 selected genes with known functions in metabolism, pigment production, development and heat shock responses. These include genes for which we expect a priori a role in thermal adaptation and, thus, varying selection pressures along a latitudinal cline, and genes we do not expect to vary clinally and can be used as controls. We identified amino acid substitution polymorphisms in 13 genes and tested these for clinal variation by correlation analysis of allele frequencies with latitude. In addition, we used two FST-based outlier methods to identify loci with higher population differentiation than expected under neutral evolution, while accounting for potentially confounding effects of population structure and demographic history. Two metabolic enzymes of the glycolytic pathway, UGP and Treh, showed clinal variation. The same loci showed elevated population differentiation and were identified as significant outliers. We found no evidence of clines in the pigmentation genes, heat shock proteins and developmental genes. However, we identified outlier loci in more localized parts of the range in the pigmentation genes yellow and black. We discuss that the observed clinal variation and elevated population divergence in UGP and Treh may reflect adaptation to a geographic thermal gradient.

  • microsatellite markers associated with genes expressed in developing wings of Bicyclus anynana butterflies
    Molecular Ecology Resources, 2009
    Co-Authors: Patricia Beldade, Maria Adelina Jeronimo, Anthony D Long
    Abstract:

    Deriving useful microsatellite markers in lepidopterans has been challenging when relying on scans of genomic DNA libraries, presumably due to repetitiveness in their genomes. We assayed 96 of 320 microsatellites identified in silico from a collection of Bicyclus anynana ESTs, in 11 independent individuals from a laboratory population. From the 68 successful assays, we identified 40 polymorphic markers including 22 with BLAST-based annotation. Nine of 12 selected polymorphic markers tested in a panel of 24 wild-caught individuals converted to successful assays and were all polymorphic. We discuss how microsatellite discovery in ESTs is an efficient strategy with important attendant advantages.

  • a gene based linkage map for Bicyclus anynana butterflies allows for a comprehensive analysis of synteny with the lepidopteran reference genome
    PLOS Genetics, 2009
    Co-Authors: Patricia Beldade, Suzanne V Saenko, Anthony D Long
    Abstract:

    Lepidopterans (butterflies and moths) are a rich and diverse order of insects, which, despite their economic impact and unusual biological properties, are relatively underrepresented in terms of genomic resources. The genome of the silkworm Bombyx mori has been fully sequenced, but comparative lepidopteran genomics has been hampered by the scarcity of information for other species. This is especially striking for butterflies, even though they have diverse and derived phenotypes (such as color vision and wing color patterns) and are considered prime models for the evolutionary and developmental analysis of ecologically relevant, complex traits. We focus on Bicyclus anynana butterflies, a laboratory system for studying the diversification of novelties and serially repeated traits. With a panel of 12 small families and a biphasic mapping approach, we first assigned 508 expressed genes to segregation groups and then ordered 297 of them within individual linkage groups. We also coarsely mapped seven color pattern loci. This is the richest gene-based map available for any butterfly species and allowed for a broad-coverage analysis of synteny with the lepidopteran reference genome. Based on 462 pairs of mapped orthologous markers in Bi. anynana and Bo. mori, we observed strong conservation of gene assignment to chromosomes, but also evidence for numerous large- and small-scale chromosomal rearrangements. With gene collections growing for a variety of target organisms, the ability to place those genes in their proper genomic context is paramount. Methods to map expressed genes and to compare maps with relevant model systems are crucial to extend genomic-level analysis outside classical model species. Maps with gene-based markers are useful for comparative genomics and to resolve mapped genomic regions to a tractable number of candidate genes, especially if there is synteny with related model species. This is discussed in relation to the identification of the loci contributing to color pattern evolution in butterflies.

  • Developmental and genetic mechanisms for evolutionary diversification of serial repeats: eyespot size in Bicyclus anynana butterflies.
    Journal of Experimental Zoology, 2008
    Co-Authors: Patricia Beldade, Vernon French, Paul M. Brakefield
    Abstract:

    Serially repeated pattern elements on butterfly wings offer the opportunity for integrating genetic, developmental, and functional aspects towards understanding morphological diversification and the evolution of individuality. We use captive populations of Bicyclus anynana butterflies, an emerging model in evolutionary developmental biology, to explore the genetic and developmental basis of compartmentalized changes in eyespot patterns. There is much variation for different aspects of eyespot morphology, and knowledge about the genetic pathways and developmental processes involved in eyespot formation. Also, despite the strong correlations across all eyespots in one butterfly, B. anynana shows great potential for independent changes in the size of individual eyespots. It is, however, unclear to what extent the genetic and developmental processes underlying eyespot formation change in a localized manner to enable such individualization. We use micromanipulations of developing wings to dissect the contribution of different components of eyespot development to quantitative differences in eyespot size on one wing surface. Reciprocal transplants of presumptive eyespot foci between artificial selection lines and controls suggest that while localized antagonistic changes in eyespot size rely mostly on localized changes in focal signal strength, concerted changes depend greatly on epidermal response sensitivities. This potentially reflects differences between the signal-response components of eyespot formation in the degrees of compartmentalization and/or the temporal pattern of selection. We also report on the phenotypic analysis of a number of mutant stocks demonstrating how single alleles can affect different eyespots in concert or independently, and thus contribute to the individualization of serially repeated traits.