Vice President of Research & Collections, Denver Museum of Nature & Science; Dinosaur paleontologist and science communicator; Author, How To Raise A Wild Child
The purpose of life is to disperse energy

The truly dangerous ideas in science tend to be those that threaten the collective ego of humanity and knock us further off our pedestal of centrality. The Copernican Revolution abruptly dislodged humans from the center of the universe. The Darwinian Revolution yanked Homo sapiens from the pinnacle of life. Today another menacing revolution sits at the horizon of knowledge, patiently awaiting broad realization by the same egotistical species.

The dangerous idea is this: the purpose of life is to disperse energy.

Many of us are at least somewhat familiar with the second law of thermodynamics, the unwavering propensity of energy to disperse and, in doing so, transition from high quality to low quality forms. More generally, as stated by ecologist Eric Schneider, "nature abhors a gradient," where a gradient is simply a difference over a distance — for example, in temperature or pressure. Open physical systems — including those of the atmosphere, hydrosphere, and geosphere — all embody this law, being driven by the dispersal of energy, particularly the flow of heat, continually attempting to achieve equilibrium. Phenomena as diverse as lithospheric plate motions, the northward flow of the Gulf Stream, and occurrence of deadly hurricanes are all examples of second law manifestations.

There is growing evidence that life, the biosphere, is no different. It has often been said the life's complexity contravenes the second law, indicating the work either of a deity or some unknown natural process, depending on one's bias. Yet the evolution of life and the dynamics of ecosystems obey the second law mandate, functioning in large part to dissipate energy. They do so not by burning brightly and disappearing, like a fire torching a forest, but through stable metabolic cycles that store chemical energy and continually reduce the solar gradient. Photosynthetic plants, bacteria, and algae capture energy from the sun and form the core of all food webs.

Virtually all organisms, including humans, are, in a real sense, sunlight transmogrified, temporary waypoints in the flow of energy. Ecological succession, viewed from a thermodynamic perspective, is a process that maximizes the capture and degradation of energy. Similarly, the tendency for life to become more complex over the past 3.5 billion years (as well as the overall increase in biomass and organismal diversity through time) is not due simply to natural selection, as most evolutionists still argue, but also to nature's "efforts" to grab more and more of the sun's flow. The slow burn that characterizes life enables ecological systems to persist over deep time, changing in response to external and internal perturbations.

Ecology has been summarized by the pithy statement, "energy flows, matter cycles. " Yet this maxim applies equally to complex systems in the non-living world; indeed it literally unites the biosphere with the physical realm. More and more, it appears that complex, cycling, swirling systems of matter have a natural tendency to emerge in the face of energy gradients. This recurrent phenomenon may even have been the driving force behind life's origins.

This idea is not new, and is certainly not mine. Nobel laureate Erwin Schrödinger was one of the first to articulate the hypothesis, as part of his famous "What is Life" lectures in Dublin in 1943. More recently, Jeffrey Wicken, Harold Morowitz, Eric Schneider and others have taken this concept considerably further, buoyed by results from a range of studies, particularly within ecology. Schneider and Dorian Sagan provide an excellent summary of this hypothesis in their recent book, "Into the Cool".

The concept of life as energy flow, once fully digested, is profound. Just as Darwin fundamentally connected humans to the non-human world, a thermodynamic perspective connects life inextricably to the non-living world. This dangerous idea, once broadly distributed and understood, is likely to provoke reaction from many sectors, including religion and science. The wondrous diversity and complexity of life through time, far from being the product of intelligent design, is a natural phenomenon intimately linked to the physical realm of energy flow.

Moreover, evolution is not driven by the machinations of selfish genes propagating themselves through countless millennia. Rather, ecology and evolution together operate as a highly successful, extremely persistent means of reducing the gradient generated by our nearest star. In my view, evolutionary theory (the process, not the fact of evolution!) and biology generally are headed for a major overhaul once investigators fully comprehend the notion that the complex systems of earth, air, water, and life are not only interconnected, but interdependent, cycling matter in order to maintain the flow of energy.

Although this statement addresses only naturalistic function and is mute with regard to spiritual meaning, it is likely to have deep effects outside of science. In particular, broad understanding of life's role in dispersing energy has great potential to help humans reconnect both to nature and to planet's physical systems at a key moment in our species' history.