Stable laws in a changing world The structure of evolutionary theories over the centuries

Abstract

Successful fundamental theories are built on quantifiable principles. This paper shows that Darwin’s inclusive theory is built on such principles and follows their rocky road into the modern, operational theories. Besides reproduction, variation, and heredity, Darwin’s conditions of diversification also include the potential for exponential (geometric) population growth and its necessarily limited nature. The Struggle for Existence (Malthus Doctrine), the Principles of Natural Selection, Competitive Exclusion (Rule of Similarity), and Divergence are mere deductions from these conditions. At present, the system dynamic theory of robust coexistence, the theory of adaptive dynamics, and the extended theory of evolution all assume Darwin’s inclusive set of principles as essentials. While Lewontin's conditions for evolution by natural selection do not provide a sufficient basis to predict the outcome of evolution, incorporating the feedbacks controlling population growth and the tradeoffs between fitness components into the core of evolutionary theory leads to the conclusion that diversification is a fundamental, inherent feature of life, and provides laws that support the determination of the expected direction of evolution in any particular case.