Recycling and growth in early evolution and today: Autocatalysis without recycling comes soon to an end - not only in early evolution

with A put in parentheses because unconstrained growth assumes infinite resources. The best illustration of the power of exponential growth is the metaphor of water lilies covering the surface of a pond: “Assume, the lilies are doubling the surface they cover on the pond every year. Three years ago they extended over one eights of the water surface and accordingly were hardly noticed, one year ago the coverage was one half, and today the pond is completely covered and all light dependent life in the pond except the lilies is doomed to die.” Malthus compared the expected growth of agricultural production of food that he assumed to increase linearly in time with a human population growing according to a geometric progression, and made the simple and up to date correct prediction of the occurrence of hunger catastrophes unless birth control is introduced. Although technology driven increases in crop yields like the “green revolution” of the nineteen sixties and seventies were unforeseeable, they did not change the principle behind the problem: More food causes population sizes to increase until the starvation limit is reached again at the level of larger population numbers. The Malthus model is so simple that it can’t be wrong, and regulation of growth by birth control is the only way out of the dilemma. We shall come back to the “green revolution” later in pointing out that one of the causes of its success is the introduction of a new process of recycling nitrogen compounds.