Human macroecology, energy use scaling, and the sustainability of cities: A look at Latin America

We take a human macroecological approach using energy as a fundamental currency to quantify the emergence and future sustainability of urban societies globally with a special look at Latin America. Energetic scaling analysis showed most modern humans in cities in Latin America and elsewhere live at densities of ~10,000 ind/km2, ~4 orders of magnitude greater than our hunter-gatherer ancestors (<1 ind/km2). Meanwhile, modern cities consume ~10,000 watts mostly in the form of extra-metabolic (e.g., fossil fuels), ~2 orders of magnitude greater than hunter-gatherer biological metabolism (~120 watts). Further analysis of World Bank data across and within nations over time showed per capita Gross Domestic Product (GDP), energy use, and CO2 emissions are lowest in predominantly rural countries, increase in urbanizing countries and are greatest in the most urban countries. For the same level of urbanization, Latin American countries show lower per capita GDP, energy use, and CO2 emissions than global averages. These trends coincide with changes in employment with rural countries employed largely in resource-extraction sectors and highly urbanized nations in service economies. Latin American countries have higher employment in resource sectors compared to most urban countries. Increasing energy use, especially fossil fuel use, underlies urbanization and changes in economic lifestyle. However, these trends cannot continue indefinitely. Latin America, because of its rich renewable and non-renewable resources, may be spared from future uncertainties inherent to complex human-nature systems including from climate change, energy scarcity, pandemics, migration, and trade agreements if it chooses to: 1) rapidly transition to renewable powered economies, and 2) reduce population and economy size within local and regional renewable biocapacities. A rapid cultural evolution is of the essence.