A Reappraisal of the Principle of Maximum Power

Living organisms continuously capture and transform free energy to survive and grow. The Maximum Power Principle (MPP) states that life evolves to maximize power—the rate of energy acquisition and conversion into useful forms—within prevailing constraints. Constraints include trophic interactions and competition, and they determine the outcome of the MPP. Biosystems that accumulate free energy faster will prevail transiently, but those that do so in a stable way will dominate in the long run. Accumulation of free energy is often approximately measurable as biomass that is useful to improve adaptation, competition, and ecological stability. Biosystems that allocate energy to long-term stable biomass—such as forests investing in wood—dominate because they secure long-term resource capture, competitive advantage, and resilience. Species and ecosystems represent different scales at which the MPP applies. In the long run, the MPP must align across scales, because a species can achieve stable growth and maximize power (i.e., accumulate free energy/useful biomass) only if the ecosystem the species lives in also maximizes its power. If a species reduces the stability and power of its ecosystem, it undermines its own long-term power-acquisition capability. This feedback harmonizes the MPP across scales over evolutionary times. Humans have evolved peculiar traits that have made them able to remove this control loop, amplifying species-level power. This enabled us to grow into a large population supported by anthropic systems that have strongly reduced the biosphere’s stability and power, resulting in a scale conflict in the MPP. Outlined in this way, the MPP provides a useful framework for understanding evolution, ecosystem development, and anthropogenic impacts.