  The factors contributing to the persistence and stability of life are
fundamental for understanding complex living systems. Organisms are commonly
challenged by harsh and fluctuating environments that are suboptimal for growth
and reproduction, which can lead to extinction. Species often contend with
unfavorable and noisy conditions by entering a reversible state of reduced
metabolic activity, a phenomenon known as dormancy. Here, we develop Spore
Life, a model to investigate the effects of dormancy on population dynamics. It
is based on Conway's Game of Life, a deterministic cellular automaton where
simple rules govern the metabolic state of an individual based on the metabolic
state of its neighbors. For individuals that would otherwise die, Spore Life
provides a refuge in the form of an inactive state. These dormant individuals
(spores) can resuscitate when local conditions improve. The model includes a
parameter alpha that controls the survival probability of spores, interpolating
between Game of Life (alpha = 0) and Spore Life (alpha = 1), while capturing
stochastic dynamics in the intermediate regime (0 < alpha < 1). In addition to
identifying the emergence of unique periodic configurations, we find that spore
survival increases the average number of active individuals and buffers
populations from extinction. Contrary to expectations, the stabilization of the
population is not the result of a large and long-lived seed bank. Instead, the
demographic patterns in Spore Life only require a small number of resuscitation
events. Our approach yields novel insight into what is minimally required for
the emergence of complex behaviors associated with dormancy and the seed banks
that they generate.
