Unmatched level of molecular convergence among deeply divergent 2 complex multicellular fungi 3 4

26 Convergent evolution is pervasive in nature, but it is poorly understood how various 27 constraints and natural selection limit the diversity of evolvable phenotypes. Here, we report 28 that, despite >650 million years of divergence, the same genes have repeatedly been co-opted 29 for the development of complex multicellularity in the two largest clades of fungi—the 30 Ascomycota and Basidiomycota. Co-opted genes have undergone duplications in both clades, 31 resulting in >81% convergence across shared multicellularity-related families. This 32 convergence is coupled with a rich repertoire of multicellularity-related genes in ancestors 33 that predate complex multicellular fungi, suggesting that the coding capacity of early fungal 34 genomes was well suited for the repeated evolution of complex multicellularity. Our work 35 suggests that evolution may be predictable not only when organisms are closely related or are 36 under similar selection pressures, but also if the genome biases the potential evolutionary 37 trajectories organisms can take, even across large phylogenetic distances. 38 . CC-BY-ND 4.0 International license It is made available under a (which was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint . http://dx.doi.org/10.1101/549758 doi: bioRxiv preprint first posted online Feb. 14, 2019;