  Research has highlighted relationships between size and scaled growth across
a large variety of biological and social organisms, ranging from bacteria,
through animals and plants, to cities an companies. Yet, heretofore,
identifying a similar relationship at the country level has proven challenging.
One reason is that, unlike the former, countries have predefined borders, which
limit their ability to grow "organically." This paper addresses this issue by
identifying and validating an effective measure of organic growth at the
country level: nighttime light emissions, which serve as a proxy of energy
allocations where more productive activity takes place. This indicator is
compared to population size to illustrate that while nighttime light emissions
are associated with superlinear growth, population size at the country level is
associated with sublinear growth. These relationships and their implications
for economic inequalities are then explored using high-resolution geospatial
datasets spanning the last three decades.
