How does complexity and diversity evolve out of simple systems, if the tendency in the universe is towards entropy in single processes over time? The first three thermodynamic laws fail to explain this process. That is why more explanations are necessary to explain why systems such as civilizations evolve, and why they do not last. While the 4th, 5th, and 6th proposed laws dictate the principles, Emergy Synthesis can give useful tools for evaluating the details of structural, economic, and social organization in ecosystems and economies.

The basis for HT’s ideas about hierarchy and energy is the maximum power principle, which explains why systems such as civilizations can self-organize out of the universal tendency towards entropy. Energy drives complexity by transformation through work into higher and higher hierarchies of complexity and order, reinforcing production through feedback loops to maximize available energy acquisition. The reformulation, Maximum (Em)Power, describes the maximum rate of emergy acquisition. “In time, through the process of trial and error, complex patterns of structure and processes have evolved…the successful ones surviving because they use materials and energies well in their own maintenance, and compete well with other patterns that chance interposes” (Odum). The maximum empower principle is a description of how self-organization develops over time, between scales, in complex systems, using energetic processes. The key processes are autocatalysis and hierarchy.

Odum, 1996, Scales of Ecological Engineering
Odum, 1996, Scales of Ecological Engineering

Higher energy flows create more spatial hierarchy and complexity (relationships), leading to more diversity (variety). Diversity requires flows of energy and is a stored manifestation of previous energy flow.  The simplest measure of complexity is probably a richness index, where you count the diversity in a sample of individuals in the population, such as the  number of types of jobs in a city’s sample, or the number of species of shells on a stretch of beach. Then number of types can be graphed against number of individuals.

“Diversity can be used to measure the state of a system in the balance between energy flows that develop diversity and those negative actions that may decrease diversity. Studies of pollution, for example, show decreases in diversity indices correlated with negative actions. Often high diversity requires large flows of energy relative to negative actions, and often time is required to develop diversity starting with low diversity states” (Odum,  1983, p. 343).  “When conditions of adaptation are severe, diversity of species is usually observed to be low. Species that prevail have energy utilized in special adaptations such as special biochemical systems, special organs, and special seasonal adaptive programs. Presumably, energy is being utilized for adapting to special conditions with less energy remaining for the special functions required to prevent competitive exclusion and otherwise organize species for cooperative coexistence” (p. Odum, 1983, p. 345).

In plant succession, multiple seeding and initial colonization constitute the choice generator, whereas mineral cycles and developing food chains provide choice machines for rewarding the plants by developing feedback loops. . . In higher organisms, selection may be programmed into the behavior of managerial species such as carnivores. In humans, the introduction of will, consciousness, and group-favoring motivations (e.g. religious, economic, egoistic) further specializes the selection of subsystems. These mechanisms help maximize empower”(Odum, 2007, p. 233).

Loose associations of mobile organisms are found in lower levels of the energy hierarchy, whereas concentrated, intricately connected, monolithic rigid structures tend to develop where power flows are highly concentrated in hierarchical centers (Odum, 2007, p. 230).

Without power excess, not much change of structure and information is possible, and losses of structure may occur (Odum, 2007, p. 238). . . In human affairs, the evolution of complex industries with specialized occupations is [a process of speciation and insulation.] Each industry receives selective reinforcement and economic rewards for contribution to the larger economy. Whereas maximizing expansion takes precedence during times of growth on excess resources, contributing to the rest of the system takes priority at other times (Odum, 2007, p. 241).

Transformities can therefore play sometimes the role of efficiency indicators and sometimes the role of hierarchical position indicators. Both of these aspects are strongly related with the complexity of an ecosystem” (Brown & Ulgiati, 2009, p. 314).

Further analysis through emergy signatures can further inform us as to the forces that drive system complexity. What changes in complexity result from alterations such as pollution or unsustainable activities? How do quantity and quality changes in emergy flows impact development? One example using energy signatures is depicted below and in Brown & Ulgiati (2009).

S. Ulgiati, M.T. Brown / Communications in Nonlinear Science and Numerical Simulation 14 (2009) 317. Emergy signatures mangroves vs. corn
Dr. Odum goes to Congress mid 1970s