Darwin’s conditions of life required for natural selection
June 2, 2013 | James Kohl
Essay Re: Charles Robert Darwin (1809–1882). Origin of Species. The Harvard Classics. 1909–14.
Introduction: Few people seem to have examined cause and effect from Darwin’s perspective, as it is portrayed in the excerpts below. Clearly, conditions of life are nutrient-dependent and pheromone-controlled in species from microbes to man. Thus, adaptive evolution must be examined within those biological constraints.
IV Natural Selection; or the Survival of the Fittest
Summary of Chapter Excerpt with my emphasis:
“IF under changing conditions of life organic beings present individual differences in almost every part of their structure, and this cannot be disputed; if there be, owing to their geometrical rate of increase, a severe struggle for life at some age, season, or year, and this certainly cannot be disputed; then, considering the infinite complexity of the relations of all organic beings to each other and to their conditions of life, causing an infinite diversity in structure, constitution, and habits, to be advantageous to them, it would be a most extraordinary fact if no variations had ever occurred useful to each being’s own welfare, in the same manner as so many variations have occurred useful to man. But if variations useful to any organic being ever do occur, assuredly individuals thus characterised will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance, these will tend to produce offspring similarly characterised. This principle of preservation, or the survival of the fittest, I have called Natural Selection.”
My comment: How many people can place Natural Selection into its proper context? In the summary paragraph above, Natural Selection follows from conditions of life that we now know are epigenetically effected by nutrients and their metabolism to species-specific pheromones. We also know that nutrients must be selected before they can be metabolized to pheromones that control reproduction. For comparison, in the context of mutations theory, no one seems capable of answering questions about what is selected.
In my model, selection is for nutrients (food). The nutrients metabolize to pheromones that signal reproductive fitness in species that sexually reproduce. Pheromones are selected in species that sexually reproduce because pheromones signal nutrient-dependent reproductive fitness. How are mutations involved in adaptive evolution (species diversification)?
V. Laws of Variation
Effects of Changed Conditions Excerpts with my emphasis:
“…the greater variability of species having wider ranges than of those with restricted ranges, lead to the conclusion that variability is generally related to the conditions of life to which each species has been exposed during several successive generations.”
“When a variation is of the slightest use to any being, we cannot tell how much to attribute to the accumulative action of natural selection, and how much to the definite action of the conditions of life.”
“Instances could be given of similar varieties being produced from the same species under external conditions of life as different as can well be conceived; and, on the other hand, of dissimilar varieties being produced under apparently the same external conditions. Again, innumerable instances are known to every naturalist, of species keeping true, or not varying at all, although living under the most opposite climates. Such considerations as these incline me to lay less weight on the direct action of the surrounding conditions, than on a tendency to vary, due to causes of which we are quite ignorant.”
My comment: Some of us now know about the cause and effect relationships that link differences in surrounding conditions to adaptive evolution in species from microbes to man. Since Darwin’s time, we have learned that these surrounding conditions are the conditions that clearly involve epigenetic effects of nutrients and the metabolism of nutrients to pheromones, which control reproduction.
Those who understand the requirements for nutrient-dependent pheromone-controlled adaptive evolution are unlikely to attempt to explain how the same external conditions cause dissimilar varieties of species or to theorize about Natural Selection for mutations via predation. Indeed, as Darwin inferred, people who lay less weight on the epigenetic effects (e.g., direct effects) of the sensory environment, and instead posit mutations theory (e.g., mutation-driven changes in the color of the peppered moths), seem to be “quite ignorant.”
What’s worst, however, is that some people have adopted Darwin’s theory without knowing that he claimed ignorance of cause and effect. It appears that he also predicted his ignorance might continue — as it obviously has. However, I doubt that he would have predicted his theory would lead to more ignorance in the context of ecological, social, neurogenic, and socio-cognitive niche construction.
I like to think that Darwin expected advocates of his theory to first include his conditions of life, which are nutrient-dependent and pheromone-controlled, before moving on to theories of how Natural Selection might occur. By placing Darwin’s ‘conditions of life’ first, advocates of his theory need not have bastardized it via incorporation of “causes of which we are [still] quite ignorant.”
Comparatively speaking, we still know nothing about how mutations could possible contribute to adaptive evolution at a time when we know precisely how nutrient-dependent pheromone-controlled adaptive evolution occurs in species from microbes to man.