In the past, the religious community has dealt with this conundrum. Shamans, priests, and preachers have claimed exclusive revelation about the answer. Nowadays, science -- our new religion -- has taken up the challenge. Instead of being divinely inspired, however, modern teachers are institutionally accredited. Which, like faith, also has the disquieting feel of knuckling under to authority, for the paranoid among us.
The popular press has for some time published volumes on the subject of the electric basis of life. Two such examples are the recent The Spark of Life by Dame Frances Ashcroft and from 1985 Robert O. Becker's The Body Electric. Each of these works explores the function of electricity within and among the basic building blocks of the body -- cells. However, Nick Lane, a biochemist in the Department of Genetics, Evolution and Environment at University College London, takes a rather more in-depth look at the mystery in his The Vital Question. (A presentation by Dr. Lane can be found here.)
Although all three books have at their core the idea of bioelectricity being what powers living cells, Dr. Lane's book goes furthest into the hows and whys of the matter, explaining the difference between electricity, the flow of negatively charged electrons, and proticity, the flow of positively charged protons, an idea first formulated by Peter D. Mitchell. "Essentially all living cells power themselves through the flow of protons...." The harvesting of power from "...proton gradients...is universal across all life on earth...." (page 13)A major tenet of Lane's thesis is that single-celled life arose some 4 billion years ago around alkaline hydrothermal vents on the deep ocean floor. Eventually, two radically different forms of life emerged, though both were based on the same energy gradient structure. Those two forms were bacteria and archaea -- what are termed the prokaryotes (from the Greek 'before the nucleus'). Complex cells -- the eukaryotes ('true nucleus') which make up all the rest of the plethora of life on this planet -- came about, according to Dr. Lane, as a result of a synthesis between the other two, "an endosymbiosis in which a bacterium got inside an archaeon, enabling the evolution of vastly more complex cells." (pages 13 - 14) He further states that there arose a founder population of essentially identical cells which happened only "on a single occasion -- and all plants, animals, algae and fungi evolved from this founder population." (page 40)
Eukaryotes harnessed the savings in energy which came from a simplified gene structure; they had much more power at their disposal. The metabolic rate (energy per gene) of eukaryotes exceeds by several factors that of the prokaryotes. Human beings "use about 2 milliwatts of energy per gram -- or some 130 watts for an average person weighting 65 kg [143.3 lbs], a bit more than a standard 100 watt light bulb. That may not sound like a lot, but per gram it is a factor of 10,000 more than the sun". (page 64) Each one of us literally burns brighter than the sun.
In the earliest times of life on Earth, this huge energy supply drove the explosive diversification of flora, fauna, and microbes. Interestingly, "there is a deep and disturbing discontinuity at the very heart of biology". (page 21) One of Lane's more startling propositions is that evolutionary biology is not predictive. That is, even if we knew all the starting perimeters, we could not foresee the forms which life would take. Just as the Uncertainty Principle means that both the trajectory and the position of an atomic particle cannot be known simultaneously, and Chaos Theory means patterns of repetition cannot be predicted, so the course of life can never be charted. Freedom, stark and beautiful, holy and terrifying, is in our very genes.
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