Dissecting supergene: evidence for recombination suppression among multiple functional loci within inversions.

Supergenes 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 set 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 an 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 showed that the supergene controlling the striking wing-pattern polymorphism displayed by this species contains many 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 associated with colour variations only in morphs controlled by inversions, indicating that they were recruited after the formation of these 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.

From the formation of embryonic appendages to the color of wings: Conserved and novel roles of aristaless1 in butterfly development

Highly diverse butterfly wing patterns have emerged as a powerful system for understanding the genetic basis of phenotypic variation. While the genetic basis of this pattern variation is being clarified, the precise developmental pathways linking genotype to phenotype are not well understood. The gene aristaless, which plays a role in appendage patterning and extension, has been duplicated in Lepidoptera. One copy, aristaless1, has been shown to control a white/yellow color switch in the butterfly Heliconius cydno, suggesting a novel function associated with color patterning and pigmentation. Here we investigate the developmental basis of al1 in embryos, larvae and pupae using new antibodies, CRISPR/Cas9, RNAi, qPCR assays of downstream targets and pharmacological manipulation of an upstream activator. We find that Al1 is expressed at the distal tips of developing embryonic appendages consistent with its ancestral role. In developing wings, we observe Al1 accumulation within developing scale cells of white H. cydno during early pupation while yellow scale cells exhibit little Al1 at this timepoint. Reduced Al1 expression is also associated with yellow scale development in al1 knockouts and knockdowns. We also find that Al1 expression appears to downregulate the enzyme Cinnabar and other genes that synthesize and transport the yellow pigment, 3–Hydroxykynurenine (3-OHK). Finally, we provide evidence that Al1 activation is under the control of Wnt signaling. We propose a model in which high levels of Al1 during early pupation, which are mediated by Wnt, are important for melanic pigmentation and specifying white portions of the wing while reduced levels of Al1 during early pupation promote upregulation of proteins needed to move and synthesize 3-OHK, promoting yellow pigmentation. In addition, we discuss how the ancestral role of aristaless in appendage extension may be relevant in understanding the cellular mechanism behind color patterning in the context of the heterochrony hypothesis.

Reassessment on the monophyly of the fruit-piercing moth, Eudocima bilberg, 1820 (Lepidoptera: Erebidae) using molecular data

Eudocima Billberg, 1820 is a group of moths known for their fruit-piercing behaviour. Members of this group are easily distinguished for their bright colour, hind wing patterns, and the robustness of their body. However, the monophyly of this genus is still in dispute. Based on morphological characters, a current study on 48 species of this genus showed that Eudocima is not a monophyletic group. We conducted a preliminary analysis of 25 species of Eudocima based on 632-bp sequences of cytochrome oxidase 1 (COI) to reassess the monophyly of this genus. Using Maximum Parsimony (MP) method, we ran a number of data sets to reconstruct the most appropriate phylogenetic tree. The result showed that Eudocima is a monophyletic group based on a nucleotide weighting of transversion: transitions = 2:1, despite the very low Jackknife support. This result should not be taken as a final conclusion because only about 60% of Eudocima species were included in our analysis. An upcoming study involving all members of this genus is necessary in order to reassess the putative monophyly of this genus.

Conserved roles of Distal-less and spalt in regulating butterfly melanic patterns

Simple spot patterns are proposed to be ancestral to more complex eyespot patterns found on the wings of butterflies. Two genes, Distal-less (Dll) and spalt (sal), are known to be involved in two separate functions in establishing nymphalid butterfly eyespots: in the differentiation of their central signaling cells, or foci, necessary for eyespot ring formation, and in scale melanisation. However, little is known about the functions of these genes in the development of more primitive spot patterns. Here, we study the roles of Dll and sal in the development of spots and other melanic wing patterns of the Indian cabbage white, Pieris canidia, a pierid butterfly. We examined the expression pattern of both genes in developing larval and pupal wings and explored their functions using the CRISPR/Cas9 system. In P. canidia, both Dll and sal are expressed in the tips and along the margin of pupal wings, areas of future scale melanisation. Additionally, sal alone, is expressed in the future black spot patterns. CRISPR knockouts of Dll and sal showed that both genes are required for promoting melanic scales in the areas where they are expressed. Both Dll and sal also function as repressors of the pteridine pigment pathway. We conclude that both genes share a conserved role in promoting scale melanisation, across pierid and nymphalid butterflies, but are unlikely to be involved in differentiating spot centers. The genetic and developmental mechanisms that set up the location of spots and eyespots are likely distinct and independently evolved in each lineage.

Understanding the design of warning signals: a predator’s view

Animal warning signals show remarkable diversity, yet subjectively appear to share visual features that make defended prey stand out and look different from more cryptic palatable species. Here we develop and apply a computational model that emulates avian visual processing of pattern and colour to Lepidopteran wing patterns to show that warning signals have specific neural signatures that set them apart not only from the patterns of undefended species but also from natural scenes. For the first time, we offer an objective and quantitative neural-level definition of warning signals based on how the pattern generates neural activity in the brain of the receiver. This opens new perspectives for understanding and testing how warning signals function and evolve, and, more generally, how sensory systems constrain general principles for signal design.

A widely diverged locus involved in locomotor adaptation in Heliconius butterflies

Heliconius butterflies have undergone adaptive radiation and therefore serve as an excellent system for exploring the continuum of speciation and adaptive evolution. However, there is a long-lasting paradox between their convergent mimetic wing patterns and rapid divergence in speciation. Here, we characterize a locus that consistently displays high divergence among Heliconius butterflies and acts as an introgression hotspot. We further show that this locus contains multiple genes related to locomotion and conserved in Lepidoptera. In light of these findings, we consider that locomotion traits may be under selection, and if these are heritable traits that are selected for, then they might act as species barriers.

Assessment of Morphometric Indices Related to Vernal Flight in Migratory Buntings

Migratory songbirds fly over long distances to avoid adverse conditions at their breeding and wintering grounds, and this phenomenon is known as ‘migration’. This migratory phenomenon is highly energy demanding. The present study was aimed to analyze the morphometric analysis of body mass, beak, wings, tail, and tarsus length of two migratory finches i.e., red-headed (RHB) and black-headed buntings (BHB) to investigate whether they showed differences in their morphological attributes. This observational study shows an understanding of the characterization of wing patterns and differences in the length of tarsus, tail, beak, and wings of both species. The size of the beak, tail, and wings of BHB is significantly different when compared to RHB. In addition, body mass was significantly high in BHB than that of RHB during their spring migration (preparatory phase). T

Semantische Kämpfe im Kampf um die Wähler. Zur diskursiven Konstruktion rechtspopulistischer Deutungsmuster

<p>The struggle to establish certain patterns of interpretation in collective social knowledge is fought by means of semantics. Collective knowledge and at the same time certain meanings are linguistically constructed. In this respect, a “dispute about the matter” can be viewed as a “dispute about words”, that is, a semantic battle (Felder, 2006, p. 1). In this sense, power is exercised through semantics. The subject of this paper is the analysis of the right-wing patterns of interpretation in the political discourse of the 21st century, in fact polyphonic first-person narrators, an attempt at capturing its typical features and at reconstructing the right-wing political narrative on the nation/Volk promoted by politicians during their meetings with voters. </p>

Rampant genome-wide admixture across the Heliconius radiation

How frequent is gene flow between species? The pattern of evolution is typically portrayed as a phylogenetic tree, yet gene flow between good species may be an important mechanism in diversification, spreading adaptive traits and leading to a complex pattern of phylogenetic incongruence. This process has thus far been studied mainly among a few closely related species, or in geographically restricted areas such as islands, but not on the scale of a continental radiation. Using a nearly complete genomic representation of 47 species in the genus, we demonstrate that admixture has played a role throughout the evolution of the charismatic Neotropical butterflies Heliconius. Modeling of phylogenetic networks based on the exome uncovers up to 13 instances of interspecific gene flow. Admixture is detected among the relatives of H. erato, as well as between the ancient lineages leading to modern clades. Interspecific gene flow played a role throughout the evolution of the genus, although the process has been most frequent in the clade of H. melpomene and relatives. We identify H. hecalesia and relatives as putative hybrids, including new evidence for introgression at the loci controlling the mimetic wing patterns. Models accounting for interspecific gene flow yield a more complete picture of the radiation as a network, which will improve our ability to study trait evolution in a realistic comparative framework.

Geographical distribution of Emesis Fabricius (Lepidoptera: Riodinidae) in Mexico: Updated checklist and temporal patterns

We present a synthesis of the existing information on the genus Emesis Fabricius in Mexico concerning biogeographical patterns and taxonomical aspects. Emesis is the most diverse genus of Emesidini with 57 species and subspecies, with Mexico as the northern limit of this Neotropical genus. We analyzed 5434 specimens of the Lepidoptera Collection of the MZFC, UNAM and compared them with specimens from collections of Mexico, Central and South America. Taxonomic determination and corroboration were made by analysis of wing patterns and genitalia. Geographic distribution and phenology were obtained from the database MARIPOSA. We present an updated list of Emesis of Mexico, with 17 species and subspecies. For each species, we provide information on phenology, geographic, altitudinal, and vegetation distributions. We discuss taxonomic and undersampling concerns for some species, as well as spatial and temporal patterns with special reference to vegetation types and biogeographic provinces in Mexico.