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We consider the available genomes (total DNA content) of autonomous organisms as strings of symbols from a four‐letter alphabet corresponding to their molecular components (or bases), and define “words” as continuous sequences of letters with a given length. With the aim of distinguishing between genomes and non‐functional DNA chains, we devise a description of random letter substitutions along a genetic string, and show each of the extant genomes to be more robust against point mutations than chains obtained by randomly reordering its word frequencies.

We show a widely accepted proof of the self‐thinning rule offered by Enquist et al. to be mathematically incomplete, as it does not identify the plant mass distributions that satisfy a condition implicitly used in the proof. We propose a method to guide the search for such mass distributions, based on a requirement of maximum mass diversity under the appropriate constraints. This generic method allows construction of a probability density that incorporates the available information on a given stochastic variable, and we illustrate its use through the calculation of a continuous mass distribution for the self‐thinning rule that satisfies the implicit condition mentioned above. We suggest a biological justification of maximum mass diversity, as a corollary to the random and unbiased nature of the source of diversity in Darwin's principle.

Potentization of homoeopathic medicines by successive dilutions and succussion at each step is interpreted in terms of stochastic resonance, a non-linear response of certain systems when perturbed by noise and a weak periodic signal, which increasingly enhanced at the output as the magnitude of the noise grows towards an optimal value for maximum signal amplification. The possible relevance of stochastic resonance in other physiological phenomena like the kindling effect, where epileptic convulsions are induced in rats and other animals by periodic stimulation of the brain with weak electric signals, is also considered.