1. Breeding for inter-individual interactions: from theory to practice

Inter-individual interactions within and between species are pervasive in both animals and plants. The phenotype of an individual can therefore depend on its neighbors. To capture the genetic basis of such a phenotypic plasticity, its impact on the response to selection and ultimately adaptation, extended genetic models were developed in evolutionary biology as well as animal and plant breeding (Hamilton, 1964; Griffing, 1967; Willham, 1963). They allow to select individuals that have a favorable genetic value for their own performance (direct effect) but also a less detrimental, or even beneficial, impact (indirect/social effect) on other group members and neighbors in general. In this symposium, we aim to cover the theoretical and practical developments of these models, with the objective to inspire new breeding approaches.

The symposium will focus on the concepts of social breeding value, indirect genetic effect and multilevel selection. It aims at gathering researchers interested in these concepts, whatever the species they study, to exchange over approaches for the genetic dissection (e.g., via GWAS) and genomic prediction of inter-individual interactions. This includes innovative experimental designs and statistical models for deciphering their genetic bases, their temporalities over the life cycles of individuals, and their interaction with external factors (abiotic, biotic, human), notably in the context of climate change and biodiversity collapse. We will also focus on understanding and predicting evolutionary changes in inter-individual interactions across generations, with the objective to integrate them in breeding schemes for farmed animals, perennials, and annual crops. This will include coupling genetic approaches with more mechanistic (eco)physiological modeling.