×VerfasserIn
	0000-0003-3742-7692
	1238919367
	Department of Ecology and Evolution, University of Lausanne, Lausanne CH-1015, Switzerland
	Institute for Biosciences, University of Rostock, Rostock 18059, Germany

×VerfasserIn
	0000-0002-3340-7785
	Department of Ecology and Evolution, University of Lausanne, UNIL Sorge, Le Biophore, CH - 1015 Lausanne, Switzerland
	Biodiversity and Evolution Unit, Department of Biology, Lund University. Ekologihuset, Sölvegatan 37, 223 62 Lund, Sweden

×VerfasserIn
	0000-0002-2322-8193
	Department of Ecology and Evolution, University of Lausanne, UNIL Sorge, Le Biophore, CH - 1015 Lausanne, Switzerland

×VerfasserIn
	0000-0001-9014-8356
	Department of Ecology and Evolution, University of Lausanne, UNIL Sorge, Le Biophore, CH - 1015 Lausanne, Switzerland

×VerfasserIn
	0000-0003-1945-5374
	Department of Ecology and Evolution, University of Lausanne, UNIL Sorge, Le Biophore, CH - 1015 Lausanne, Switzerland

Alexander Brandt     Guillaume Lavanchy     Vincent Mérel     Luca Soldini     Morgane Massy     Zoé Dumas     Emelyne Gaudichau     Marjorie Labédan     Falon Pasquier Genoud     Marc Bastardot     Tanja Schwander

Hybridogenesis as an intermediate step between sexual reproduction and parthenogenesis in stick insects

[accepted author manuscript], University of Rostock, 2026

In: Proceedings of the National Academy of Sciences (PNAS) , Vol. 123, No. 22, e2535700123, 2026

https://doi.org/10.18453/rosdok_id00005578

Abstract: Many organisms reproduce through non-canonical modes such as parthenogenesis or hybridogenesis (clonal transmission of one parent’s chromosomes), but whether these arise abruptly or stepwise from each other remains unclear. We address this in the stick-insect genus Bacillus , which harbors several hybrid lineages with diverse reproductive modes. From haplotype-resolved phylogenies of >500 wild-caught individuals, we infer a single, recent (~8,000 years) origin of all hybrids. The ancestral hybrid reproduced via hybridogenesis, which subsequently diversified into parthenogenesis and, twice independently, into triploid lineages. Laboratory crosses recapitulate this trajectory, where each step facilitated the next. These findings reveal how a single genomic perturbation can act as a catalyst for evolutionary innovation, turning the loss of sex into a driver of diversification rather than a dead end.

Artikel   Freier Zugang