Friday, January 3, 2014

Day Light, Night Light, and Control of Fire

If "disruptive" lighting technology is the answer, what's the question? We know it's more than "how can we make lighting more energy efficient?"- CFLs did that at the cost of quality of light. Perhaps we can look at human evolution for some more interesting questions, and eventually, answers.

A 2009 book by Harvard biological anthropologist Richard Wrangham, Catching Fire, presents a startling new theory: control of fire was the defining event in human evolution, as it led to cooking, which allowed us to absorb nutrients more effectively and led to big brains. Wrangham’s theory is particularly well argued and seems to be generally well received in the scientific community. One big fan (besides me) is food writer Michael Pollan, who cites the theory several times in his latest work,Cooked, which, among many things, explores how cooking impacts social cohesion.

Wrangham is mainly concerned with fire’s dramatic impact on human alimentary processes and the changes that followed from that. Cooked food is absorbed much more easily than raw (even wild animals prefer it), so it ultimately freed up time previously spent in chewing, digesting, and other tedious forms of processing raw food. Humans who adapted well to the control of fire obviously survived to evolve and prosper. What if we examined the evolutionary effects of fire on vision? If fire was indeed the evolutionary turning point, doesn’t it make sense to ask whether some of our behavior around light and energy use may be instinctive or genetically driven? Could we have a “fire gene” (or genes)?

We know that light has a strong impact on cognition, behavior, and emotional response. One rarely considered behavior that lighting impacts is how we use energy, as lighting is the most visible use of electricity, which can be seen as “sublimated fire.” We’ve lost a direct connection to energy since the electrification of the world. One way to understand energy in a very visceral way is to gather wood for cooking while backpacking in the wilderness- energy spent on acquiring fuel can be directly measured in the output of the fuel one gathers.

If we could incorporate an evolutionary biology perspective in research on light, what would that mean?

It may provide a new theoretical framework for understanding light and lighting, especially spectral design, in the context of new technologies- our current exposure to ubiquitous “broken spectra” light sources is analogous to the empty calorie diets we now consume, as Soraa CTO Mike Krames points out in his latest blog. Humans obviously evolved with only two types of light spectrum- daylight (in all its permutations) and “night light” (from incandescent sources). Exposing ourselves for long periods to light with unnatural spectra that deviate in basic ways from these two seems as unadvisable as ingesting pesticides, breathing polluted air, and eating a diet of overly refined industrial foods.

Research done from evolutionary perspective might give lighting design more and richer kinds of evidence upon which to strengthen practitioners’ role as “behavior modifiers” in the built environment. The best designers today operate equally well on both technical and aesthetic levels, but it’s the behavioral part of design that is least understood, and probably most important.

The revolution in lighting technology we are now undergoing provides us with unprecedented flexibility in designing lighting for healthier, more productive, and efficient buildings. Much more research is needed for us to develop a better understanding of the behavioral impacts of light on humans and other living organisms, so that we can finally apply optimal lighting on a wide scale in the near future.