Endosperm in angiosperms and placenta in eutherians are convergent innovations for efficient embryonic nutrient transfer. Despite advantages, this reproductive strategy incurs metabolic costs that maternal parents disproportionately shoulder, leading to potential inter-parental conflict over optimal offspring investment. Genomic imprinting-parent-of-origin-biased gene expression-is fundamental for endosperm and placenta development and has convergently evolved in angiosperms and mammals, in part, to resolve parental conflict.
View Article and Find Full Text PDFTelomeres are nucleoprotein complexes with a crucial role of protecting chromosome ends. It consists of simple repeat sequences and dedicated telomere-binding proteins. Because of its vital functions, components of the telomere, for example its sequence, should be under strong evolutionary constraint.
View Article and Find Full Text PDFAlthough intrinsic postzygotic reproductive barriers can play a fundamental role in speciation, their underlying evolutionary causes are widely debated. One hypothesis is that incompatibilities result from genomic conflicts. Here, I synthesize the evidence that conflict generates incompatibilities in plants, thus playing a creative role in plant biodiversity.
View Article and Find Full Text PDFBarriers to reproduction are often how progress in speciation is measured. Nonetheless, an unresolved question concerns the extent to which reproductive barriers diminish gene flow between incipient species. The Sierra Nevada foothill endemic Mimulus glaucescens and the widespread M.
View Article and Find Full Text PDFUnderstanding which reproductive barriers contribute to speciation is essential to understanding the diversity of life on earth. Several contemporary examples of strong hybrid seed inviability (HSI) between recently diverged species suggest that HSI may play a fundamental role in plant speciation. Yet, a broader synthesis of HSI is needed to clarify its role in diversification.
View Article and Find Full Text PDFAbstractHybrid seed inviability is a common reproductive barrier in angiosperms. Recent work suggests that the rapid evolution of hybrid seed inviability may, in part, be due to conflict between maternal and paternal optima for resource allocation to developing offspring (i.e.
View Article and Find Full Text PDFWith the rise of affordable next-generation sequencing technology, introgression-or the exchange of genetic materials between taxa-has become widely perceived to be a ubiquitous phenomenon in nature. Although this claim is supported by several keystone studies, no thorough assessment of the frequency of introgression across eukaryotes in nature has been performed to date. In this manuscript, we aim to address this knowledge gap by examining patterns of introgression across eukaryotes.
View Article and Find Full Text PDFDespite a century of genetic analysis, the evolutionary processes that have generated the patterns of exceptional genetic and phenotypic variation in the model organism Drosophila melanogaster remains poorly understood. In particular, how genetic variation is partitioned within its putative ancestral range in Southern Africa remains unresolved. Here, we study patterns of population genetic structure, admixture, and the spatial structuring of candidate incompatibility alleles across a global sample, including 223 new accessions, predominantly from remote regions in Southern Africa.
View Article and Find Full Text PDFNeural circuits must both execute the behavioral repertoire of individuals and account for behavioral variation across species. Understanding how this variation emerges over evolutionary time requires large-scale phylogenetic comparisons of behavioral repertoires. Here, we describe the evolution of walking in fruit flies by capturing high-resolution, unconstrained movement from 13 species and 15 strains of drosophilids.
View Article and Find Full Text PDFAs we uncover the ubiquity of hybridization in nature, determining how natural selection acts on hybrids has newfound importance for speciation. A study in PLOS Biology uses threespine stickleback to detect a genomic signature of ecological incompatibilities.
View Article and Find Full Text PDFEcological divergence is a fundamental source of phenotypic diversity between closely related species, yet the genetic architecture of most ecologically relevant traits is poorly understood. Differences in elevation can impose substantial divergent selection on both complex, correlated suites of traits (such as life-history), as well as novel adaptations. We use the species complex to assess if the divergence in elevation is accompanied by trait divergence in a group of closely related perennials and determine the genetic architecture of this divergence.
View Article and Find Full Text PDFPhilos Trans R Soc Lond B Biol Sci
August 2020
Intrinsic postzygotic barriers can play an important and multifaceted role in speciation, but their contribution is often thought to be reserved to the final stages of the speciation process. Here, we review how intrinsic postzygotic barriers can contribute to speciation, and how this role may change through time. We outline three major contributions of intrinsic postzygotic barriers to speciation.
View Article and Find Full Text PDFGenomic conflicts may play a central role in the evolution of reproductive barriers. Theory predicts that early-onset hybrid inviability may stem from conflict between parents for resource allocation to offspring. Here, we describe M.
View Article and Find Full Text PDFLittle is known about how microbial communities shape the expression of plant phenotypes and phenotypic correlations. This is precisely the question that O'Brien et al. addressed using populations of highland teosinte, a wild relative of maize.
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