Structural Complexity Growth as a Fundamental Law of Nature. Multilevel Increase in Complexity, Frozen Accidents, and Transitory Forms in Macroevolution

The available evidence suggests that structural complexity growth is a fundamental law of nature. In living organisms, the structural complexity becomes structural-functional complexity, but the tendency to its growth is conserved. Structural-functional complexity growth in living organisms is a multilevel process that consists of frozen coincidences of complexity growth events at different levels. Frozen coincidences are stabilized by structural-functional feedback interactions and conserved in geological time by natural selection. Populations of tumor-bearing animals could be unstable transitory forms in progressive evolution. Atypical tumor organs can represent transitory structures and should be looked for in fossil records.