Data from: Mimicry refinement: Phenotypic variations tracking the local optimum

1. Müllerian mimicry between chemically defended preys is a textbook example of natural selection favouring phenotypic convergence onto a shared warning signal. Studies of mimicry have concentrated on deciphering the ecological and genetic underpinnings of dramatic switches in mimicry association, producing a well-known mosaic distribution of mimicry patterns across geography. However, little is known about the accuracy of resemblance between natural co-mimics when the local phenotypic optimum varies. 2. In this study, using analyses of wing shape, pattern and hue, we quantify multimodal phenotypic similarity between butterfly co-mimics sharing the so-called postman pattern in different localities with varying species composition. 3. We show that subtle but consistent variation between populations of the localised species, Heliconius timareta thelxinoe, enhance resemblance to the abundant co-mimics which drive the mimicry in each locality. 4. Those results suggest that rarer co-mimics track the changes in the phenotypic optimum caused by gradual changes in the composition of the mimicry community, providing insights into the process by which intra-specific diversity of mimetic pattern may arise. Furthermore, our results suggest a multimodal evolution of similarity, with coordinated convergence in different features of the phenotype such as wing outline, pattern and hue. 5. Finally, multilocus genotyping allows estimating local hybridization rates between H. timareta and co-mimic H. melpomene in different populations, raising the hypothesis that mimicry refinement between closely-related co-mimics may be enhanced by adaptive introgression at loci modifying the accuracy of resemblance

Functionalizing Gold Nanoparticles with Calix[4]arenes Monolayers for Enhancing Selectivity and Stability in ORR Electrocatalysis

International audienceFunctionalized gold nanoparticles with a single layer of calix[4]arenes demonstrate remarkable electrocatalytic activity for the reduction of oxygen in water. Calix-based nanocatalysts display increased selectivity and stability compared to their citrate-stabilized counterparts. These nanohybrids operate according to a 4-electrons process with good electrocatalytic performance as well as great robustness.Des nanoparticules d’or fonctionnalisées avec une monocouche de calix[4]arènes démontrent une activité électrocatalytique remarquable pour la réduction du dioxygène en milieu aqueux. Les nanocatalyseurs à base de calix[4]arènes présentent une sélectivité et une stabilité accrues par rapport à leurs homologues citrates. Ces nanohybrides fonctionnent selon un processus de réduction à 4 électrons avec de bonnes performances électrocatalytiques ainsi qu’une grande robustesse

Phenotypic and genotypic caracterisation of the samples

The data file includes a full list of specimen with collection places, sexes and species, a genotype spreadsheet with the microsatellites alleles and several spreadsheets with the data quantifying the different modalities of the phenotype (details below). Each specimen is identified by a unique id in the genotype/phenotype data. Please refer to the specimen information for its caracteristics. For all: FW = forewing HW = hindwing v = ventral d = dorsal * Specimen information: All collection details on the specimen used in the study (cf supplementary information) * Genotype (microsatellites): Each line is a specimen. Each column is a microsatellite locus. 000000 are missing data. * Shape data (morphometrics): Each line is a specimen. The 14 (HW) or 15 (FW) columns corresponds to 14 or 15 landmarks with 2 coordinates (X, Y). * Pattern data (Colour pattern modelling): Each line is a specimen. The columns are coordinates along the principal components. * Shape data (outline): Each line is a specimen. The columns are coordinates along the principal components. * Colour data (spectrometry): Spreadsheets called "Red, Yellow or Black" The first column is the wavelength. Each column corresponds to the reflectance of the given colour (in % of the white reference) for an individual. Measurements are averaged over two spectra (one measured on the right wing, the other on the left wing - or twice on the same wing if the other wing was damaged)

Association mapping of colour variation in a butterfly provides evidence that a supergene locks together a cluster of adaptive loci

International audienceSupergenes are genetic architectures associated with discrete and concerted variation in multiple traits. It has long been suggested that supergenes control these complex polymorphisms by suppressing recombination between sets of coadapted genes. However, because recombination suppression hinders the dissociation of the individual effects of genes within supergenes, there is still little evidence that supergenes evolve by tightening linkage between coadapted genes. Here, combining a landmark-free phenotyping algorithm with multivariate genome-wide association studies, we dissected the genetic basis of wing pattern variation in the butterfly Heliconius numata . We show that the supergene controlling the striking wing pattern polymorphism displayed by this species contains several independent loci associated with different features of wing patterns. The three chromosomal inversions of this supergene suppress recombination between these loci, supporting the hypothesis that they may have evolved because they captured beneficial combinations of alleles. Some of these loci are, however, associated with colour variations only in a subset of morphs where the phenotype is controlled by derived inversion forms, indicating that they were recruited after the formation of the inversions. Our study shows that supergenes and clusters of adaptive loci in general may form via the evolution of chromosomal rearrangements suppressing recombination between co-adapted loci but also via the subsequent recruitment of linked adaptive mutations. This article is part of the theme issue ‘Genomic architecture of supergenes: causes and evolutionary consequences’

New D-π-A-conjugated organic sensitizers based on α-pyranylidene donors for dye-sensitized solar cells

International audienceA series of new push-pull org. dyes incorporating a cyanoacrylic acid group as electron acceptor unit and α-chalcogenopyranylidene group (X = S; O) as electron donor unit has been synthesized, characterized and used as sensitizer for dye-sensitized solar cells (DSSCs). For the first time, α-pyranylidene and thiopyranylidene groups, have been evaluated in DSSC. To obtain the thermodn. values of the solar cell, an investigation of their electrochem. (CV) and optical properties (UV-vis absorption spectroscopy) is also reported

Data from: Crossing fitness valleys: empirical estimation of adaptive landscape associated with polymorphic mimicry

Characterising the fitness landscapes associated with polymorphic adaptive traits enables the investigation of the mechanisms allowing transitions between fitness peaks. Here, we explore how natural selection can promote genetic mechanisms preventing heterozygous phenotypes from falling into non-adaptive valleys. Polymorphic mimicry is an ideal system to investigate such fitness landscapes, because the direction of selection acting on complex mimetic colour patterns can be predicted by the local mimetic community composition. Using more than 5,000 artificial butterflies displaying colour patterns exhibited by the polymorphic Müllerian mimic Heliconius numata, we directly tested the role of wild predators in shaping fitness landscapes. We compared predation rates on mimetic phenotypes (homozygotes at the supergene controlling colour pattern), intermediate phenotypes (heterozygotes), exotic morphs (absent from the local community) and palatable cryptic phenotypes. Exotic morphs were significantly more attacked than local morphs, highlighting predators’ discriminatory capacities. Overall, intermediates were attacked twice as much as local homozygotes, suggesting the existence of deep fitness valleys promoting strict dominance and reduced recombination between supergene alleles. By including information on predators’ colour perception, we also showed that protection on intermediates strongly depends on their phenotypic similarity to homozygous phenotypes and that ridges exist between similar phenotypes, which may facilitate divergence in colour patterns

Data from: Does divergent selection predict the evolution of mate preference and reproductive isolation in the tropical butterfly genus Melinaea (Nymphalidae: Ithomiini)?

Many studies have shown that speciation can be facilitated when a trait under divergent selection also causes assortative mating. In Müllerian mimetic butterflies, a change in wing colour pattern can cause reproductive isolation. However, colour pattern divergence does not always lead to reproductive isolation. Understanding how divergent selection affects speciation requires identifying the mechanisms that promote mate preference and/or choosiness. This study addresses whether shifts in wing colour pattern drives mate preference and reproductive isolation in the tropical butterfly genus Melinaea (Nymphalidae: Ithomiini), and focuses on five taxa that form a speciation continuum, from subspecies to fully recognized species. Using genetic markers, wing colour pattern quantification, male pheromone characterization and behavioural assays of mating preference, we characterize the extent of genetic and phenotypic differentiation between taxa and compare it to the level of reproductive isolation. We show strong premating isolation between the closely related species M. satevis and M. marsaeus, in addition to genetic and phenotypic (colour pattern and pheromones) differentiation. By contrast, M. menophilus and M. marsaeus consist of pairs of subspecies that differ for colour pattern but that cannot be differentiated genetically. Pheromonal differentiation of subspecies was significant only for M. marsaeus, although most individuals were indistinguishable. Melinaea menophilus and M. marsaeus also differ in the strength of assortative mating, suggesting that mate preference has evolved only in M. marsaeus, consistent with selection against maladaptive offspring, as subspecific “hybrids” of M. marsaeus have intermediate, non‐mimetic colour patterns, unlike those of M. menophilus which display either parental phenotypes. We conclude that a shift in colour pattern per se is not sufficient for reproductive isolation, but rather, the evolution of assortative mating may be caused by selection against maladaptive intermediate phenotypes. This study suggests that mate preference and assortative mating evolve when adaptive, and that even in the early stages of divergence, reproductive isolation can be nearly complete due to mating preferences

Morpho morphometrics: Shared ancestry and selection drive the evolution of wing size and shape in Morpho butterflies

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Hybridization and transgressive exploration of colour pattern and wing morphology in Heliconius butterflies

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Datasets for microsats, pheromone composition, and colour pattern

Data for five Melinaea taxa of north-eastern Peru, and putative hybrids between subspecies. The first spreadsheet contains the allele size for the 12 microsatellite loci used in the study, the second spreadsheet contains quantification of the different compounds present in the chemical profile of extracted male hair pencils (ie. androconial scales) obtained by GC-MS, and the third spreadsheet contains the quantification of colour pattern by Colour Pattern Modelling (CPM)