Beyond plants : how reproductive strategies could shape invasiveness and disease spread in freshwater snails [résumé]

2025

Colloque

Muller Baigorria M., Chapuis Elodie, Bonel N., Alda P.

Leblanc Olivier (ed.), Autran Daphné (ed.), V International APOMIXIS 2025 Conference : book of abstracts

Marseille (FRA) ; Montpellier : IRD ; DIADE, 2025, p. 63

International APOMIXIS 2025 Conference, V., Montpellier (FRA), 2025/09/16-19

Reproductive strategies profoundly influence evolutionary outcomes and ecological processes. Here, we extend key concepts from plant reproductive biology to the animal kingdom by focusing on freshwater snails--specifically lymnaeids--as a model system. We investigate how variation in mating systems, including self-fertilization and outcrossing, shapes both colonization processes and disease transmission. Using an integrative framework that combines observational data, population genetics, and phylogenetic analysis, we examine how these reproductive modes influence both the establishment success and long-term persistence of snail populations. Self-fertilization, in particular, offers reproductive assurance in newly colonized or disturbed habitats where mates are scarce or environmental conditions are unstable. This strategy enables rapid population growth from a single founder, thereby facilitating expansion. However, a species that reproduces by self-fertilization for many generations shows a genomic degradation and a reduced genetic diversity that translates into a low adaptive potential, which is why self-fertilization is considered to be an evolutionary dead. In other words, all these detrimental genetic and genomic effects are predicted to drive selfing lineages to extinction on the long term. However, a group of lymnaeid snails (the genus Galba), comprising selfing snails and dating back over 20 million years, stands as a notable exception. Its persistence challenges traditional assumptions and suggests that, under specific ecological conditions?such as amphibious lifestyles and reduced interspecific competition long-term selfing may remain evolutionarily viable. We also examine how reproductive strategies intersect with epidemiological dynamics. Selfing populations, characterized by low genetic variation, may facilitate parasite transmission by sustaining genetically uniform host populations. These insights underscore the broader ecological and public health implications of reproductive strategies, particularly in the context of snail-borne zoonoses. By bridging concepts across kingdoms, our work emphasizes the importance of reproductive diversity and invites a rethinking of long-held assumptions about the evolutionary fate of selfing lineages.

Environnement, écologie générale [021ENVECO] ; Mécanismes de reproduction [076PHYBIO06] ; Maladies des animaux [080PROANI05]

Fonds IRD [F A010096557]

fdi:010096564