Speaker
Description
A distinguishing feature of eukaryotic cells is their ability to consume other cells. By contrast, prokaryotes are much more likely to engage in competitive and cooperative interactions. However, in the evolutionary transition from prokaryotes to eukaryotes, predation must have emerged from communities with primarily competitive or cooperative interactions. There are clear benefits to developing the ability to eat a competitor, but can it ever be beneficial to eat a cooperator?
We use a dynamical systems framework and invasion analysis to identify the ecological conditions under which predatory mutants can invade a system of cooperating microbes. We identify a critical threshold that determines whether an invading predator will coexist with the cooperative community or replace members. Repeatedly invading with different predators, we find that the system saturates when there are three coexisting species, though this community does not have a single optimal composition. However, if we incorporate additional costs, we find there is a single evolutionarily stable community of two cooperators and a pure predator. Ultimately, we show that it is possible for phagocytosis to evolve from a cooperative community and, moreover, coexist with the original cooperating species.
