Malthusian Relativityι**=7/3ψ
The unfolding of population dynamic feed-back selection

Natural selection time

Natural selection time is selected as the inverse of mass specific metabolism

With mass specific metabolism being selected as the pace of the biochemical, physiological and ecological processes of resource handling, we can follow Pearl (1928) and others like Brody (1945), Hill (1950), Stahl (1962) and Calder (1984), and define an overall biological time-scale

τ ∝ 1 / β

as inversely related to mass specific metabolism (β). The inverse relationship represents an expected invariance when biological time is defined from metabolic pace; but it is also a relationship that is selected directly by the mass-rescaling of the life history.

The biological time-scale is essential not only for rates of physiological processes. It is also defining the time-scale of natural selection because natural selection is selecting changes between generations.


  • Brody, S. 1945. Bioenergetics and growth. Hafner, New York.
  • Calder, W. A.I. 1984. Size, function, and life history. Harvard University Press, Cambridge.
  • Hill, A.V. 1950. the dimensions of animals and their muscular dynamics. Science of Computer Programming 38:209--230.
  • Pearl, R. 1928. The rate of living. Alfred A. Knopf, New York.
  • Stahl, W.R. 1962. Similarity and dimensional methods in biology. Science 137:205--212.