Abstract

To their dismay, children look like their parents. They are not perfect copies, and over many generations some features evaporate; but even over fifty generations features relevant to an anthropologist persist. Children perhaps can find some comfort in the fact that we are not alone: organisms in general maintain remarkably stable structures through time. In What is Life? Erwin Schrödinger famously predicted the existence of the gene, but he also asked how life manages such stability in the face of thermodynamics’ prescription that systems spontaneously move to increase their entropy. How does life escape the randomizing effects of the Second Law? Schrödinger of course recognized that there is no genuine conflict between life and thermodynamics. The Second Law applies only to closed, i.e., approximately energetically isolated, systems, yet living organisms are open systems. Although living creatures are not plugged into electrical sockets like your refrigerator, Schrödinger noted that organisms are dependent on the high quality energy of their environment. They maintain their structures at the expense of increased contributions of entropy (waste) to their environment. Life arises in the balance between the low entropy found in the environment and the entropy the organism itself throws off. Writing in the 1940’s, Schrödinger could see the general form of the answer to his question, but he lacked the resources to explain why these stable structures arose in the first place.