Fig. 1. Model of community assembly with diauxie and serial dilution.

a Tables of growth rates and resource preferences of two species α (red) and β (yellow), each capable of consuming all four available resources, R₁ to R₄. The resource preference sets the sequence in which a microbial species utilizes resources, and the corresponding rates g_Xi indicate the growth rate while consuming each resource (see “Methods”). b Diauxic growth curve of species α during one serial dilution cycle, which has 4 phases of growth on each individual resource, with rates g_α1, g_α3, g_α2, and g_α4, respectively (with a brief lag period between two phases). At the end of each dilution cycle, we dilute the population by a factor D = 100, and supply fresh resources (see “Methods”). c Resource depletion curves corresponding to (b), where each resource is represented by a different color. R₁ is exhausted at time T₁; then species α consumes R₃ which runs out at T₃, which is followed by exhaustion of R₂ at T₂, and so on. d Schematic of serial dilution experiment. During community assembly, new species are added one by one from a species pool. After each successful invasion, the system undergoes several growth-dilution cycles until it reaches a steady state. e Population dynamics corresponding to the assembly process in (d). Panels (b) and (c) correspond to a small section of this process (highlighted in gray), where the community dynamics consist only of species α (red) reaching a steady state.