Working Paper, v5: A biodiversity number with explicit speciation Alternative title: A Neutral Unified Model of Community Evolution

1 Studies focused on speciation have tried to explain the emergence of new species 2 but stopped short of studying what it means for the biodiversity patterns such as 3 abundance or diversity. Community ecologist, on the other hand, have studied how 4 such patterns are maintained, but they did not study the processes that formed the 5 basic components of these patterns. We here take advantage of recent developments 6 in speciation theory to unify neutral theories of molecular evolution and biodiversity. 7 This provides a framework that simultaneously consider community evolution in asex8 ual and sexual populations with explicit mechanisms of speciation. We first calculate 9 the expected speciation rate for two models with asexual and sexual reproduction. We 10 then use maximum likelihood to compare the biodiversity number from those two sce11 narios with the neutral theory of biodiversity assuming implicit speciation. We found 12 a new biodiversity number for the asexual and sexual reproduction models that takes 13 into account evolving genomes of individuals and a molecular filter that regulates the 14 production of viable offspring. Second, the estimated biodiversity number from the 15 asexual and the sexual reproduction models are consistently larger and lower than the 16 expected from the implicit speciation model, respectively. Asexual evolution gener17 ates higher species richness, coexistence and diversity despite its lower speciation rate 18 values when comparing with the sexual model. Thus, diversification rates, diversity 19 and coexistence depends critically on reproduction mode. We discuss the mechanisms 20 that enhance and constrain speciation rate and dramatically alter diversity and coexis21 tence in the context of molecular, sexual–asexual modes of reproduction and ecological 22 factors. 23 Short running title: A new biodiversity number