Sex unfolded: sex, asex, sexes

Roscoff (Bretagne), France, September 11-15, 2023

Deadline for application: May 4, 2023

Chairperson: Thomas Lenormand
Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Campus du CNRS, 1919 route de Mende, 34293 Montpellier Cedex 5, France

Phone: +33 (0)4 67 61 32 91

Vice-chairperson: Karine Van Doninck1 / Denis Roze2

1Molecular Biology and Evolution – C.P. 160/16, Université Libre de Bruxelles, Avenue F.D. Roosevelt, 50 B-1050 Brussels, Belgium
Phone: +32 2/650 22 14

2Station Biologique de Roscoff, Place Georges Teissier, CS90074, 29288 Roscoff Cedex, France
Phone: +33 (0)2 98 29 23 20


Sex: What is it good for? The reasons for why the vast majority of eukaryotes take a complicated detour to reproduction, when straightforward routes are available, remains a central and largely unanswered question in evolutionary biology. The complexity of reproduction ranges from clonal reproduction to meiotic parthenogenesis, self-fertilization or mating between relatives, to sexual reproduction with outcrossing. Each of these forms of reproduction directly influences the potential for adaptation and diversification of lineages and thereby the structure of biodiversity. Despite that, our understanding of the evolution of reproductive and genetic systems is still fragmentary. Even some of the most fundamental questions remain open, such as: what is the evolutionary advantage of sexual reproduction? Why is sex maintained in most species? How do sex-asex transitions occur? What are the selective pressures acting on the evolution of recombination? Why is recombination suppressed on sex chromosomes? What are the genomic and evolutionary consequences of recombination arrest? How do sexual conflicts influence the evolution of genetic systems?

Sophisticated theoretical approaches developed over the past 40 years have generated insights into the potential costs and benefits of different reproductive systems and how they can vary under different ecological scenarios. Furthermore, there is an accumulating number of novel and/or unexpected findings from organisms with different reproductive and genetic systems for which there is currently no, or only an incomplete, theoretical framework for a full conceptual interpretation. Recent advances have been made in four main directions: (1) the study of asexuals, (2) recombination, (3) sexual conflicts, and (4) sex chromosomes. The aim of the conference is to cover recent advances on these topics.

The conference will cover the following topics:

  • The genomics of asexual species
  • Sex-asex transitions
  • Meiosis modifications in parthenogenetic species
  • Recombination variation, mechanisms and evolution
  • Sex-specific selection across genomes
  • The evolution of sex determination
  • The evolution and genomics of sex chromosomes


Invited speakers
(provisional titles)

Jessica Abbott (Dept. of Biology, Lund, Sweden)
Understanding sex chromosomes using experimental evolution

Doris Bachtrog (University of California, Berkeley, USA)
Dynamic gene content evolution on Y chromosomes

Jens Bast (Institute for Zoology, University of Cologne, Köln, Germany)
Evolutionary persistence in the absence of sex

Astrid Böhne (Zoological Research Museum Alexander Koenig - Leibniz Institute for Animal Biodiversity, Bonn, Germany)
A tour de sex (chromosomes) in cichlid fish

Tim Connallon (Monash University, Victoria, Australia)
Revisiting the relation between genetic dominance and adaptation on sex chromosomes

Etienne Danchin (Institut Sophia Agrobiotech, Sophia Antipolis, France)
Comparative genomics of sexually and asexually-reproducing root-knot nematodes highlight idiosyncrasies linked to reproductive modes

Marie Delattre (Ecole Normale Supérieure de Lyon, Lyon, France)
Origin and consequences of autopseudogamy in Mesorhabditis nematodes

Nicolas Galtier (Institut des Sciences de l’Evolution Montpellier, France)
Genome evolution after sex is lost

Tatiana Giraud (Laboratoire ESE, Université Paris-Sud XI, Orsay, France)
Stepwise evolution of recombination suppression on fungal mating-type chromosomes

Sylvain Glémin (UMR ECOBIO, Rennes, France)
Diversity, determinants, and consequences of recombination landscapes in flowering plants

Christoph Haag (Centre d’Ecologie Fonctionnelle et Evolutive, Montpellier, France)
Contagious asexuality reveals selection acting during evolutionary transitions to parthenogenesis

Simone Immler (University of East Anglia, Norwich, United Kingdom)
The evolutionary implications of haploid selection in predominanty diploid organisms

Mark Kirkpatrick (University of Texas, Austin, Texas, USA)
Sexually Antagonistic Selection in Humans

Thomas Lenormand (Centre d’Ecologie Fonctionnelle et Evolutive, Montpellier, France)
Regulators and the evolution of sex chromosomes

Michael Lynch (Biodesign Insitute, Arizona State University, Tempe, USA)
The evolutionary genomics of sex and recombination in Daphnia

Gabriel Marais (CIBIO-InBIO, Universidade do Porto, Vairão, Portugal)
DNA sequence of the giant sex chromosomes of the dioecious plant Silene latifolia

Raphael Mercier (Max Planck Institute for Plant Breeding Research, Cologne, Germany)
What limits meiotic crossovers?

Pavitra Muralidhar (University of California Davis, USA)
Stabilizing selection on polygenic traits inhibits sex chromosome transitions

Aline Muyle (Centre d’Ecologie Fonctionnelle et Evolutive, Montpellier, France)
Epigenetics and sex chromosome evolution in Silene

Sally Otto (Dpt Zoology, University of British Columbia, Vancouver, Canada)
Selective interference and the evolution of sex

Bret Payseur (University of Wisconsin-Madison, USA)
Evolution of Recombination Rate on Broad and Fine Genomic Scales

Max Reuter (University College London, London, United Kingdom)
Sexually antagonistic genetic variation in fruit flies

Tanja Schwander (University of Lausanne, Switzerland)
Consequences of parthenogenesis for genome evolution in stick insects (and other animals)

Henrique Teotónio (Institut de Biologie de l'Ecole Normale Supérieure, Paris, France)
Adaptation and selection on a recombination rate modifier

Karine Van Doninck (Université Libre de Bruxelles, Brussels, Belgium)
DNA repair during non-reductional meiosis in the asexual rotifer Adineta vaga

Stephen Wright (University of Toronto, Canada)
Evolutionary causes and consequences of the spread of the recent neo sex chromosome

Alison Wright (University of Sheffield, United Kingdom)
Evolution and genomics of sexual dimorphism


Deadline for application: May 4, 2023


Registration fee (including board and lodging)
480 € for PhD students
730 € for other participants

Application for registration

The total number of participants is limited to 115 and all participants are expected to attend for the whole duration of the conference. Selection is made on the basis of the affinity of potential participants with the topics of the conference. Scientists and PhD Students interested in the meeting should deposit online before the deadline:

- their curriculum vitae
- the proof of their student status

- the list of their main publications for the 3 last years
- the abstract of their presentation:

The abstract must respect the following template:

- First line: title
- Second line: list of authors
- Third line: author's addresses
- Fourth line: e-mail of the presenting author

Abstract should not exceed 600 words. No figures.

After the deadline, the organizers will select the participants. Except in some particular cases approved by the Chairperson, it is recommended that all selected participants present their work during the conference, either in poster form or by a brief in- session talk. The organizers choose the form in which the presentations are made. No payment will be sent with application. Information on how and when to pay will be mailed in due time to those selected.