Humans individually evolve by..?

This 2020 UK evolutionary biology article was part of a “Fifty years of the Price equation” issue:

“Genetic and non-genetic inheritance usually produce a phenotype [the composite of an organism’s characteristics, including its developmental, biophysical, and behavioral traits] through a highly complex developmental process that also relies on many features of the world over which the parents have little, if any, control. As a consequence, the relationship between the phenotypes of parents and offspring, the offspring–parent distribution, can take on many forms and vary from one place or time to another.

The extension of transmission and quantitative genetic models retain the assumption that the relationship between inheritance and phenotypic variation is such that it is sufficient to focus on the transmissibility of inherited variants or additive variance rather than phenotype development.

The concept of heredity as a developmental process is a more significant departure from traditional notions of inheritance. The mechanisms of non-genetic inheritance, such as parental behaviour, do not only affect the parent–offspring resemblance, but also the generation of variation and individual fitness.

Any feature of the parents, including their DNA sequence, physiology and behaviour can carry information about the conditions that the offspring will encounter. That this information content itself must be an evolving property is perhaps most evident when heredity is viewed as a developmental process; a developmental perspective is particularly useful when the aim is to study how the evolutionary process itself is evolving.” “Different perspectives on non-genetic inheritance illustrate the versatile utility of the Price equation in evolutionary biology”

This article and the “Fifty years of the Price equation” issue’s other articles had numerous mentions of individual evolution and behavior. They acknowledged “a diversity of perspectives” but I didn’t see my 2015 page’s perspective that it’s up to each individual to mold their own phenotype. In it, the Price equation prompted the question:

“How does a phenotype influence its own change?”

which I applied to a person individually evolving.

The article and the issue’s other articles tinkered with equations, and cited plant, animal, and human studies with frameworks that didn’t include investigating causes for the observed effects. These often wasted resources by providing solutions that addressed symptoms instead of addressing the uninvestigated causes.

For example, I didn’t see any mentions of how an individual’s pain may drive their phenotype. Pain induced by threats to survival are common parts of animal experiments that create and investigate phenotypes of epigenetic responses to stressors.

Regarding possible human applicability, how can a person remedy their undesirable traits and acquire desirable traits without addressing a root cause?

Unlike animals, people can therapeutically resolve underlying causes without the timing, duration, and intensity of efforts being externally determined. A human’s efforts to change their phenotype don’t have to mimic animal studies’ forcible approaches with drugs, etc., directed on someone else’s schedule. Addressing pain may be required for such efforts.

The article also promoted an outdated paradigm of epigenetic transgenerational inheritance:

“The transgenerational stability of some epigenetic states may fall within the same range as the stability of behaviours that are learnt from parents. Quantifying the environmental sensitivity and transgenerational stability of epigenetic variation has emerged as a major research focus over the past decade.”

As explained in Transgenerational epigenetic inheritance of thyroid hormone sensitivity:

“Observing the same phenotype in each generation is NOT required for transgenerational epigenetic inheritance to exist. Animal transgenerational studies have shown that epigenetic inheritance mechanisms may both express different phenotypes for each generation, and entirely skip a phenotype in one or more generations.”

Considering only “transgenerational stability of epigenetic variation” as proof will misinterpret this supporting evidence.

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