Decoding the genomic basis of the first fungus farmers: the attine ants

Objectif

Ants are fascinating organisms well known for their highly organized societies. Their ancestor underwent a major evolutionary transition from solitary life to superorganismal colonies, with obligate reproductive division of labour between queens and workers. Notably, the attine ants pioneered agriculture around 66 million years ago by cultivating fungus for food, predating human farming by tens of millions of years. This partnership gave rise to four agricultural systems, including the leafcutter ants, whose colonies with millions of polymorphic, task-specialized workers dominate Neotropical ecosystems and are major agricultural pests. Fungus-growing ants are a textbook example of symbiosis, their mutualism is so tightly integrated that both partners have lost traits essential for independent survival, illustrating evolutionary trade-offs at the individual level in favour of collective benefits. The overarching goal of this project is to discover the genomic and regulatory principles that transformed attines into agricultural superorganisms. I propose four research packages that will: 1) uncover the genomic changes in ants underlying the origin of fungus farming and the stepwise upscaling of attine agriculture; 2) elucidate the molecular mechanisms, including brain development, by which division of labour and caste determination shaped colony organization in fungus-growing ants; 3) identify reciprocal and complementary genomic adaptations underlying ant–fungus coevolution; 4) elucidate the uncovered gene functions associated with caste differentiation and symbiotic specializations through gene knockdown experiments. By integrating comparative genomics, transcriptomics, co-evolutionary analyses, and functional validations, ATTOMICS will move decisively beyond descriptive studies to establish a novel genomic and functional framework for understanding how agriculture could reshape insect societies, positioning attine ants as a world-leading model for symbiosis.