I think what the link says is badly flawed because it isn't 'evolution' in the Darwinian sense of the word as it deviates far too much from that precise meaning and thus the word is used far too loosely here. For example, it says:
Bejan also points out that rolling stones evolve to have less friction so that they can travel further. That is, they become rounder over time.
yes but that isn't due to natural selection now, is it? It is because of them being worn down by impact and friction.
In addition, they don't evolve via genetically inheritable mutations.
I think it is important to distinguish and avoid confusion here between the more generic but vaguer English dictionary meaning of the word 'evolve' which means just 'change', not necessarily via Darwinian evolution, and the more specialized and specific meaning of the word 'evolve' as in change specifically via Darwinian evolution.
In his previous work on animal size, lifespan and travel distance, Bejan also demonstrated that, despite their differences, all animals should have roughly the same number of breaths per lifetime. In much the same way, Bejan shows in his new work that, all other things being equal, all rolling stones and eddies have the same number of revolutions before their energy dissipates through friction.
an arbitrary and irrelevant connection between the two things since, unlike animals, stones don't tend to have that property as a result of natural selection and genetically inheritable mutations thus this is not an indicator of 'evolution' in the same sense of the word.