Among the continuing mysteries in science is the quest for understanding how complex life emerged from the basic elements of the earth. Of all the elements, the one most directly associated with life on this planet is undoubtedly carbon. “Organisms”—fundamental units of life—are derived from “organic” compounds—which in turn connote the chemistry of carbon (periodic table code C). The geologist Robert Hazen lyrically writes about carbon’s place in the universe and suggests that the creative orchestra of the cosmos perennially plays a “Symphony in C.” The role of carbon in forming complex molecules is singularly significant in crafting the building blocks of life.
It’s not surprising that when scientists began to think through various plausible scenarios for the evolution of life, carbon chemistry was central. One of the founders of modern microbiology, Louis Pasteur, convincingly dispensed with the notion of spontaneous generation of life from nonlife via an “essence” or “soul.” He did so with a simple experiment in 1869 by showing that sterile grape juice could never convert to wine on its own. There needed to be some injection of living organisms—like yeast—to start the fermentation process. Yet, Pasteur’s seminal insight still left us begging the question of how yeasts emerged from inanimate chemicals. At some level, we are still trying to find that pathway to the first “living” entity emerging from chemicals.
To understand how geology and chemistry conspired to create life, we would need to bring physics to the party, too! One of the founders of quantum physics Erwin Schrodinger noted in 1944 in his seminal treatise What Is Life?— all living beings share a common physical feature—they self-organize into structures from highly distributed chemical building blocks. In the language of physics, the development of life decreases “entropy” — which is often defined rather simplistically as the level of “disorder” in a system. More accurately, entropy is a measure of the possible arrangements of a system or the distribution of energy or resultant information in a system.
Energy efficiency and the power of organisms is a fascinating area for considering what the Caltech biophysicist Rob Phillips has termed “molecular vitalism.” Using nothing more than the traditional blackboard and colored chalks, he enthralled the audience at the Kavli Insitute by calculating on the fly the amount of power generated per kilogram by a bacterium, a human, and the sun. Astonishingly, the sun—an inanimate, giant, nuclear fusion reactor—produces around 0.0001 watts per kilogram; a human being produces around one watt per kilogram, and a bacterium produces around one thousand watts per kilogram. Energy transfer is a key attribute of life, and this is not linked to intelligence but to molecular efficiency.
Connecting physics to geology suggests that the only way life could have evolved was under environmental conditions that allowed for low-entropy states to emerge in an overall context that would still increase the full entropy of a system. Weather systems like tornadoes and hurricanes are examples of such an emergence of lower-entropy subregions through stochastic processes while overall entropy increases. What conditions mimic such energy gradients, and what elements could facilitate the emergence of life-giving molecules? We know now that the primordial-soup and lightening hypothesis that was popularized by the famous Miller-Urey experiment could only provide proximate conditions in specific organic synthesis.
Research funding on the origins of life is sporadic. The Simons Foundation, started by mathematician and hedge fund manager Jim Simon, has been a major donor of scientific inquiry in this arena. Philadelphia-based Templeton Foundation is focused on “grand questions” with more philosophical underpinnings that consider theology as well as the rise of artificial intelligence forms. Independent networks of universities have also been emerging to fuel research and writing on this topic. The Dutch government announced a 40 million Euros grant for the next 10 years in their “Evolving Life from Non-life” (Evolf) program.
As we consider ways of sustaining life on earth in terms of planetary boundaries and novel technological solutions, we need to still consider the very fundamental question of how life emerged as a research priority, particularly in deep sea hydrothermal vents. The research must be approached with humility and scientists must calmly engage in arguments also with those who are using the very complexity of life-giving molecules to posit scientifically problematic “creationist” arguments. However, these debates need to be carefully curated so as to generate less heat and more light on some of the most perplexing existential questions for the public.
