Sex in eukaryotes

Sex predominates in eukaryotes, despite its short-term disadvantage when compared to asexuality. Myriad models have suggested that short-term advantages of sex may be sufficient to counterbalance its twofold costs. However, despite decades of experimental work seeking evidence of such short-term advantages, no evolutionary mechanism has yet achieved broad recognition as explanation for the maintenance of sex.

We explore here, through lineage-selection models, the conditions favouring the maintenance of sex.

We simulated the mechanisms underlying the higher extinction rates of asexual lineages than of their sexual counterparts. We linked extinction rates to the ecological and/or genetic features of lineages, thereby providing the first formalisation of the only figure included in Darwin’s “The origin of species”.

Our results indicate that the long-term advantages of sex and lineage selection may provide the most satisfactory explanations for the maintenance of sex in eukaryotes. Short-term benefits may play a role, but it is also essential to take into account the selection of lineages for a thorough understanding of the maintenance of sex.

This web site

You can find here the source code and result examples of the second model we proposed in the paper. This model is inspired from Darwin's diagram and is explained in details in the associated paper.

Using the "Browser", you can select a set of parameters and visualize the trees generated with the model.

Alternatively, the C source code of the model is available under the GNU general public licence in the "Downloads" section.