@article{11479, abstract = {Understanding population divergence that eventually leads to speciation is essential for evolutionary biology. High species diversity in the sea was regarded as a paradox when strict allopatry was considered necessary for most speciation events because geographical barriers seemed largely absent in the sea, and many marine species have high dispersal capacities. Combining genome-wide data with demographic modelling to infer the demographic history of divergence has introduced new ways to address this classical issue. These models assume an ancestral population that splits into two subpopulations diverging according to different scenarios that allow tests for periods of gene flow. Models can also test for heterogeneities in population sizes and migration rates along the genome to account, respectively, for background selection and selection against introgressed ancestry. To investigate how barriers to gene flow arise in the sea, we compiled studies modelling the demographic history of divergence in marine organisms and extracted preferred demographic scenarios together with estimates of demographic parameters. These studies show that geographical barriers to gene flow do exist in the sea but that divergence can also occur without strict isolation. Heterogeneity of gene flow was detected in most population pairs suggesting the predominance of semipermeable barriers during divergence. We found a weak positive relationship between the fraction of the genome experiencing reduced gene flow and levels of genome-wide differentiation. Furthermore, we found that the upper bound of the ‘grey zone of speciation’ for our dataset extended beyond that found before, implying that gene flow between diverging taxa is possible at higher levels of divergence than previously thought. Finally, we list recommendations for further strengthening the use of demographic modelling in speciation research. These include a more balanced representation of taxa, more consistent and comprehensive modelling, clear reporting of results and simulation studies to rule out nonbiological explanations for general results.}, author = {De Jode, Aurélien and Le Moan, Alan and Johannesson, Kerstin and Faria, Rui and Stankowski, Sean and Westram, Anja M and Butlin, Roger K. and Rafajlović, Marina and Fraisse, Christelle}, issn = {1752-4571}, journal = {Evolutionary Applications}, number = {2}, pages = {542--559}, publisher = {Wiley}, title = {{Ten years of demographic modelling of divergence and speciation in the sea}}, doi = {10.1111/eva.13428}, volume = {16}, year = {2023}, } @article{12514, abstract = {The concept of a “speciation continuum” has gained popularity in recent decades. It emphasizes speciation as a continuous process that may be studied by comparing contemporary population pairs that show differing levels of divergence. In their recent perspective article in Evolution, Stankowski and Ravinet provided a valuable service by formally defining the speciation continuum as a continuum of reproductive isolation, based on opinions gathered from a survey of speciation researchers. While we agree that the speciation continuum has been a useful concept to advance the understanding of the speciation process, some intrinsic limitations exist. Here, we advocate for a multivariate extension, the speciation hypercube, first proposed by Dieckmann et al. in 2004, but rarely used since. We extend the idea of the speciation cube and suggest it has strong conceptual and practical advantages over a one-dimensional model. We illustrate how the speciation hypercube can be used to visualize and compare different speciation trajectories, providing new insights into the processes and mechanisms of speciation. A key strength of the speciation hypercube is that it provides a unifying framework for speciation research, as it allows questions from apparently disparate subfields to be addressed in a single conceptual model.}, author = {Bolnick, Daniel I. and Hund, Amanda K. and Nosil, Patrik and Peng, Foen and Ravinet, Mark and Stankowski, Sean and Subramanian, Swapna and Wolf, Jochen B.W. and Yukilevich, Roman}, issn = {1558-5646}, journal = {Evolution: International journal of organic evolution}, number = {1}, pages = {318--328}, publisher = {Oxford University Press}, title = {{A multivariate view of the speciation continuum}}, doi = {10.1093/evolut/qpac004}, volume = {77}, year = {2023}, } @article{12159, abstract = {The term “haplotype block” is commonly used in the developing field of haplotype-based inference methods. We argue that the term should be defined based on the structure of the Ancestral Recombination Graph (ARG), which contains complete information on the ancestry of a sample. We use simulated examples to demonstrate key features of the relationship between haplotype blocks and ancestral structure, emphasizing the stochasticity of the processes that generate them. Even the simplest cases of neutrality or of a “hard” selective sweep produce a rich structure, often missed by commonly used statistics. We highlight a number of novel methods for inferring haplotype structure, based on the full ARG, or on a sequence of trees, and illustrate how they can be used to define haplotype blocks using an empirical data set. While the advent of new, computationally efficient methods makes it possible to apply these concepts broadly, they (and additional new methods) could benefit from adding features to explore haplotype blocks, as we define them. Understanding and applying the concept of the haplotype block will be essential to fully exploit long and linked-read sequencing technologies.}, author = {Shipilina, Daria and Pal, Arka and Stankowski, Sean and Chan, Yingguang Frank and Barton, Nicholas H}, issn = {1365-294X}, journal = {Molecular Ecology}, keywords = {Genetics, Ecology, Evolution, Behavior and Systematics}, number = {6}, pages = {1441--1457}, publisher = {Wiley}, title = {{On the origin and structure of haplotype blocks}}, doi = {10.1111/mec.16793}, volume = {32}, year = {2023}, } @article{14452, abstract = {The classical infinitesimal model is a simple and robust model for the inheritance of quantitative traits. In this model, a quantitative trait is expressed as the sum of a genetic and an environmental component, and the genetic component of offspring traits within a family follows a normal distribution around the average of the parents’ trait values, and has a variance that is independent of the parental traits. In previous work, we showed that when trait values are determined by the sum of a large number of additive Mendelian factors, each of small effect, one can justify the infinitesimal model as a limit of Mendelian inheritance. In this paper, we show that this result extends to include dominance. We define the model in terms of classical quantities of quantitative genetics, before justifying it as a limit of Mendelian inheritance as the number, M, of underlying loci tends to infinity. As in the additive case, the multivariate normal distribution of trait values across the pedigree can be expressed in terms of variance components in an ancestral population and probabilities of identity by descent determined by the pedigree. Now, with just first-order dominance effects, we require two-, three-, and four-way identities. We also show that, even if we condition on parental trait values, the “shared” and “residual” components of trait values within each family will be asymptotically normally distributed as the number of loci tends to infinity, with an error of order 1/M−−√⁠. We illustrate our results with some numerical examples.}, author = {Barton, Nicholas H and Etheridge, Alison M. and Véber, Amandine}, issn = {1943-2631}, journal = {Genetics}, number = {2}, publisher = {Oxford Academic}, title = {{The infinitesimal model with dominance}}, doi = {10.1093/genetics/iyad133}, volume = {225}, year = {2023}, } @article{14556, abstract = {Inversions are structural mutations that reverse the sequence of a chromosome segment and reduce the effective rate of recombination in the heterozygous state. They play a major role in adaptation, as well as in other evolutionary processes such as speciation. Although inversions have been studied since the 1920s, they remain difficult to investigate because the reduced recombination conferred by them strengthens the effects of drift and hitchhiking, which in turn can obscure signatures of selection. Nonetheless, numerous inversions have been found to be under selection. Given recent advances in population genetic theory and empirical study, here we review how different mechanisms of selection affect the evolution of inversions. A key difference between inversions and other mutations, such as single nucleotide variants, is that the fitness of an inversion may be affected by a larger number of frequently interacting processes. This considerably complicates the analysis of the causes underlying the evolution of inversions. We discuss the extent to which these mechanisms can be disentangled, and by which approach.}, author = {Berdan, Emma L. and Barton, Nicholas H and Butlin, Roger and Charlesworth, Brian and Faria, Rui and Fragata, Inês and Gilbert, Kimberly J. and Jay, Paul and Kapun, Martin and Lotterhos, Katie E. and Mérot, Claire and Durmaz Mitchell, Esra and Pascual, Marta and Peichel, Catherine L. and Rafajlović, Marina and Westram, Anja M and Schaeffer, Stephen W. and Johannesson, Kerstin and Flatt, Thomas}, issn = {1420-9101}, journal = {Journal of Evolutionary Biology}, publisher = {Wiley}, title = {{How chromosomal inversions reorient the evolutionary process}}, doi = {10.1111/jeb.14242}, year = {2023}, } @article{14552, abstract = {Interactions between plants and herbivores are central in most ecosystems, but their strength is highly variable. The amount of variability within a system is thought to influence most aspects of plant-herbivore biology, from ecological stability to plant defense evolution. Our understanding of what influences variability, however, is limited by sparse data. We collected standardized surveys of herbivory for 503 plant species at 790 sites across 116° of latitude. With these data, we show that within-population variability in herbivory increases with latitude, decreases with plant size, and is phylogenetically structured. Differences in the magnitude of variability are thus central to how plant-herbivore biology varies across macroscale gradients. We argue that increased focus on interaction variability will advance understanding of patterns of life on Earth.}, author = {Robinson, M. L. and Hahn, P. G. and Inouye, B. D. and Underwood, N. and Whitehead, S. R. and Abbott, K. C. and Bruna, E. M. and Cacho, N. I. and Dyer, L. A. and Abdala-Roberts, L. and Allen, W. J. and Andrade, J. F. and Angulo, D. F. and Anjos, D. and Anstett, D. N. and Bagchi, R. and Bagchi, S. and Barbosa, M. and Barrett, S. and Baskett, Carina and Ben-Simchon, E. and Bloodworth, K. J. and Bronstein, J. L. and Buckley, Y. M. and Burghardt, K. T. and Bustos-Segura, C. and Calixto, E. S. and Carvalho, R. L. and Castagneyrol, B. and Chiuffo, M. C. and Cinoğlu, D. and Cinto Mejía, E. and Cock, M. C. and Cogni, R. and Cope, O. L. and Cornelissen, T. and Cortez, D. R. and Crowder, D. W. and Dallstream, C. and Dáttilo, W. and Davis, J. K. and Dimarco, R. D. and Dole, H. E. and Egbon, I. N. and Eisenring, M. and Ejomah, A. and Elderd, B. D. and Endara, M. J. and Eubanks, M. D. and Everingham, S. E. and Farah, K. N. and Farias, R. P. and Fernandes, A. P. and Fernandes, G. W. and Ferrante, M. and Finn, A. and Florjancic, G. A. and Forister, M. L. and Fox, Q. N. and Frago, E. and França, F. M. and Getman-Pickering, A. S. and Getman-Pickering, Z. and Gianoli, E. and Gooden, B. and Gossner, M. M. and Greig, K. A. and Gripenberg, S. and Groenteman, R. and Grof-Tisza, P. and Haack, N. and Hahn, L. and Haq, S. M. and Helms, A. M. and Hennecke, J. and Hermann, S. L. and Holeski, L. M. and Holm, S. and Hutchinson, M. C. and Jackson, E. E. and Kagiya, S. and Kalske, A. and Kalwajtys, M. and Karban, R. and Kariyat, R. and Keasar, T. and Kersch-Becker, M. F. and Kharouba, H. M. and Kim, T. N. and Kimuyu, D. M. and Kluse, J. and Koerner, S. E. and Komatsu, K. J. and Krishnan, S. and Laihonen, M. and Lamelas-López, L. and Lascaleia, M. C. and Lecomte, N. and Lehn, C. R. and Li, X. and Lindroth, R. L. and Lopresti, E. F. and Losada, M. and Louthan, A. M. and Luizzi, V. J. and Lynch, S. C. and Lynn, J. S. and Lyon, N. J. and Maia, L. F. and Maia, R. A. and Mannall, T. L. and Martin, B. S. and Massad, T. J. and Mccall, A. C. and Mcgurrin, K. and Merwin, A. C. and Mijango-Ramos, Z. and Mills, C. H. and Moles, A. T. and Moore, C. M. and Moreira, X. and Morrison, C. R. and Moshobane, M. C. and Muola, A. and Nakadai, R. and Nakajima, K. and Novais, S. and Ogbebor, C. O. and Ohsaki, H. and Pan, V. S. and Pardikes, N. A. and Pareja, M. and Parthasarathy, N. and Pawar, R. R. and Paynter, Q. and Pearse, I. S. and Penczykowski, R. M. and Pepi, A. A. and Pereira, C. C. and Phartyal, S. S. and Piper, F. I. and Poveda, K. and Pringle, E. G. and Puy, J. and Quijano, T. and Quintero, C. and Rasmann, S. and Rosche, C. and Rosenheim, L. Y. and Rosenheim, J. A. and Runyon, J. B. and Sadeh, A. and Sakata, Y. and Salcido, D. M. and Salgado-Luarte, C. and Santos, B. A. and Sapir, Y. and Sasal, Y. and Sato, Y. and Sawant, M. and Schroeder, H. and Schumann, I. and Segoli, M. and Segre, H. and Shelef, O. and Shinohara, N. and Singh, R. P. and Smith, D. S. and Sobral, M. and Stotz, G. C. and Tack, A. J.M. and Tayal, M. and Tooker, J. F. and Torrico-Bazoberry, D. and Tougeron, K. and Trowbridge, A. M. and Utsumi, S. and Uyi, O. and Vaca-Uribe, J. L. and Valtonen, A. and Van Dijk, L. J.A. and Vandvik, V. and Villellas, J. and Waller, L. P. and Weber, M. G. and Yamawo, A. and Yim, S. and Zarnetske, P. L. and Zehr, L. N. and Zhong, Z. and Wetzel, W. C.}, issn = {1095-9203}, journal = {Science}, number = {6671}, pages = {679--683}, publisher = {AAAS}, title = {{Plant size, latitude, and phylogeny explain within-population variability in herbivory}}, doi = {10.1126/science.adh8830}, volume = {382}, year = {2023}, } @misc{14579, abstract = {This is associated with our paper "Plant size, latitude, and phylogeny explain within-population variability in herbivory" published in Science. }, author = {Wetzel, William}, publisher = {Zenodo}, title = {{HerbVar-Network/HV-Large-Patterns-MS-public: v1.0.0}}, doi = {10.5281/ZENODO.8133117}, year = {2023}, } @phdthesis{14058, abstract = {Females and males across species are subject to divergent selective pressures arising from di↵erent reproductive interests and ecological niches. This often translates into a intricate array of sex-specific natural and sexual selection on traits that have a shared genetic basis between both sexes, causing a genetic sexual conflict. The resolution of this conflict mostly relies on the evolution of sex-specific expression of the shared genes, leading to phenotypic sexual dimorphism. Such sex-specific gene expression is thought to evolve via modifications of the genetic networks ultimately linked to sex-determining transcription factors. Although much empirical and theoretical evidence supports this standard picture of the molecular basis of sexual conflict resolution, there still are a few open questions regarding the complex array of selective forces driving phenotypic di↵erentiation between the sexes, as well as the molecular mechanisms underlying sexspecific adaptation. I address some of these open questions in my PhD thesis. First, how do patterns of phenotypic sexual dimorphism vary within populations, as a response to the temporal and spatial changes in sex-specific selective forces? To tackle this question, I analyze the patterns of sex-specific phenotypic variation along three life stages and across populations spanning the whole geographical range of Rumex hastatulus, a wind-pollinated angiosperm, in the first Chapter of the thesis. Second, how do gene expression patterns lead to phenotypic dimorphism, and what are the molecular mechanisms underlying the observed transcriptomic variation? I address this question by examining the sex- and tissue-specific expression variation in newly-generated datasets of sex-specific expression in heads and gonads of Drosophila melanogaster. I additionally used two complementary approaches for the study of the genetic basis of sex di↵erences in gene expression in the second and third Chapters of the thesis. Third, how does intersex correlation, thought to be one of the main aspects constraining the ability for the two sexes to decouple, interact with the evolution of sexual dimorphism? I develop models of sex-specific stabilizing selection, mutation and drift to formalize common intuition regarding the patterns of covariation between intersex correlation and sexual dimorphism in the fourth Chapter of the thesis. Alltogether, the work described in this PhD thesis provides useful insights into the links between genetic, transcriptomic and phenotypic layers of sex-specific variation, and contributes to our general understanding of the dynamics of sexual dimorphism evolution.}, author = {Puixeu Sala, Gemma}, isbn = {978-3-99078-035-0}, issn = {2663-337X}, pages = {230}, publisher = {Institute of Science and Technology Austria}, title = {{The molecular basis of sexual dimorphism: Experimental and theoretical characterization of phenotypic, transcriptomic and genetic patterns of sex-specific adaptation}}, doi = {10.15479/at:ista:14058}, year = {2023}, } @article{14077, abstract = {The regulatory architecture of gene expression is known to differ substantially between sexes in Drosophila, but most studies performed so far used whole-body data and only single crosses, which may have limited their scope to detect patterns that are robust across tissues and biological replicates. Here, we use allele-specific gene expression of parental and reciprocal hybrid crosses between 6 Drosophila melanogaster inbred lines to quantify cis- and trans-regulatory variation in heads and gonads of both sexes separately across 3 replicate crosses. Our results suggest that female and male heads, as well as ovaries, have a similar regulatory architecture. On the other hand, testes display more and substantially different cis-regulatory effects, suggesting that sex differences in the regulatory architecture that have been previously observed may largely derive from testis-specific effects. We also examine the difference in cis-regulatory variation of genes across different levels of sex bias in gonads and heads. Consistent with the idea that intersex correlations constrain expression and can lead to sexual antagonism, we find more cis variation in unbiased and moderately biased genes in heads. In ovaries, reduced cis variation is observed for male-biased genes, suggesting that cis variants acting on these genes in males do not lead to changes in ovary expression. Finally, we examine the dominance patterns of gene expression and find that sex- and tissue-specific patterns of inheritance as well as trans-regulatory variation are highly variable across biological crosses, although these were performed in highly controlled experimental conditions. This highlights the importance of using various genetic backgrounds to infer generalizable patterns.}, author = {Puixeu Sala, Gemma and Macon, Ariana and Vicoso, Beatriz}, issn = {2160-1836}, journal = {G3: Genes, Genomes, Genetics}, keywords = {Genetics (clinical), Genetics, Molecular Biology}, number = {8}, publisher = {Oxford University Press}, title = {{Sex-specific estimation of cis and trans regulation of gene expression in heads and gonads of Drosophila melanogaster}}, doi = {10.1093/g3journal/jkad121}, volume = {13}, year = {2023}, } @article{14463, abstract = {Inversions are thought to play a key role in adaptation and speciation, suppressing recombination between diverging populations. Genes influencing adaptive traits cluster in inversions, and changes in inversion frequencies are associated with environmental differences. However, in many organisms, it is unclear if inversions are geographically and taxonomically widespread. The intertidal snail, Littorina saxatilis, is one such example. Strong associations between putative polymorphic inversions and phenotypic differences have been demonstrated between two ecotypes of L. saxatilis in Sweden and inferred elsewhere, but no direct evidence for inversion polymorphism currently exists across the species range. Using whole genome data from 107 snails, most inversion polymorphisms were found to be widespread across the species range. The frequencies of some inversion arrangements were significantly different among ecotypes, suggesting a parallel adaptive role. Many inversions were also polymorphic in the sister species, L. arcana, hinting at an ancient origin.}, author = {Reeve, James and Butlin, Roger K. and Koch, Eva L. and Stankowski, Sean and Faria, Rui}, issn = {1365-294X}, journal = {Molecular Ecology}, publisher = {Wiley}, title = {{Chromosomal inversion polymorphisms are widespread across the species ranges of rough periwinkles (Littorina saxatilis and L. arcana)}}, doi = {10.1111/mec.17160}, year = {2023}, }