Sexual reproduction is a trait shared by all complex life, but the complete account of its origin is missing. Virtually all theoretical work on the evolution of sex has been centered around the benefits of reciprocal recombination among nuclear genes, paying little attention to the evolutionary dynamics of multi-copy mitochondrial genomes. Here I develop a mathematical model to study the evolution of nuclear alleles inducing cell fusion in an ancestral population of clonal proto-eukaryotes. Segregational drift maintains high mitochondrial variance between clonally reproducing hosts, but the effect of segregation is opposed by cytoplasmic mixing which tends to reduce variation between cells in favor of higher heterogeneity within the cell. Despite the reduced long-term population fitness, alleles responsible for sexual cell fusion can spread to fixation. The evolution of sex requires negative epistatic interactions between mitochondrial mutations under strong purifying selection, low mutation load and weak mitochondrial-nuclear associations. I argue that similar conditions could have been maintained during the late stages of eukaryogenesis, facilitating the evolution of sexual cell fusion and meiotic recombination without compromising the stability of the emerging complex cell.
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http://dx.doi.org/10.1016/j.jtbi.2016.05.037 | DOI Listing |
Genome Res
January 2025
Institute of Plant Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China;
Sex chromosomes can expand through fusion with autosomes, thereby acquiring unique evolutionary patterns. In butterflies and moths (Lepidoptera), these sex chromosome-autosome (SA) fusions occur relatively frequently, suggesting possible evolutionary advantages. Here, we investigated how SA fusion affects chromosome features and molecular evolution in leafroller moths (Lepidoptera: Tortricidae).
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
General and Systematic Zoology, Zoological Institute and Museum, University of Greifswald, Greifswald 17489, Germany.
The sense of smell is a central sensory modality of most terrestrial species. However, our knowledge of olfaction is based on vertebrates and insects. In contrast, little is known about the chemosensory world of spiders and nothing about how they perform olfaction despite their important ecological role.
View Article and Find Full Text PDFPLoS Biol
January 2025
Department of Forest and Conservation Sciences, Department of Botany, University of British Columbia, Vancouver, Canada.
The discipline of ecology and evolutionary biology (EEB) has long grappled with issues of inclusivity and representation, particularly for individuals with systematically excluded and marginalized backgrounds or identities. For example, significant representation disparities still persist that disproportionately affect women and gender minorities; Black, Indigenous, and People of Color (BIPOC); individuals with disabilities; and people who are LGBTQIA+. Recent calls for action have urged the EEB community to directly address issues of representation, inclusion, justice, and equity.
View Article and Find Full Text PDFBMC Med
January 2025
Global Public Health, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Subang Jaya, Sunway City, Selangor, Malaysia.
Background: We aimed to identify specific multimorbidity latent classes among multi-ethnic community-dwelling adults aged ≥ 18 years in Malaysia. We further explored the risk factors associated with these patterns and examined the relationships between the multimorbidity patterns and 11-year all-cause mortality risk, as well as health-related quality of life (HRQoL).
Methods: Using data from 18,101 individuals (aged 18-97 years) from the baseline Census 2012, Health Round 2013, and Verbal Autopsies 2012-2023 of the South East Asia Community Observatory (SEACO) health and demographic surveillance system, latent class analysis was performed on 13 chronic health conditions to identify statistically and clinically meaningful groups.
Nat Plants
January 2025
Boyce Thompson Institute, Ithaca, NY, USA.
Hornworts, one of the three bryophyte phyla, show some of the deepest divergences in extant land plants, with some families separated by more than 300 million years. Previous hornwort genomes represented only one genus, limiting the ability to infer evolution within hornworts and their early land plant ancestors. Here we report ten new chromosome-scale genomes representing all hornwort families and most of the genera.
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