  It is well known that life on Earth alters its environment over evolutionary
and geological timescales. An important open question is whether this is a
result of evolutionary optimization or a universal feature of life. In the
latter case, the origin of life would be coincident with a shift in
environmental conditions. Here we present a model for the emergence of life in
which replicators are explicitly coupled to their environment through the
recycling of a finite supply of resources. The model exhibits a dynamic,
first-order phase transition from non-life to "life," where the life phase is
distinguished by selection on replicators. We show that environmental coupling
plays an important role in the dynamics of the transition. The transition
corresponds to a redistribution of matter in replicators and their environment,
driven by selection on replicators, exhibiting an explosive growth in diversity
as replicators are selected. The transition is accurately tracked by the mutual
information shared between replicators and their environment. In the absence of
successfully repartitioning system resources, the transition fails to complete,
leading to the possibility of many frustrated trials before life first emerges.
Often, the replicators that initiate the transition are not those that are
ultimately selected. The results are consistent with the view that life's
propensity to shape its environment is indeed a universal feature of
replicators, characteristic of the transition from non-life to life. We discuss
the implications of these results for understanding life's emergence and
evolutionary transitions more broadly.
