Free As The Wind: Genetic Adjustments To Existing Circumstances
According to New Testament, Jesus said that a seed sown in rocky soil won't fair too well, but a seed sown in fertile soil will grow and prosper. We today know there are many variables to consider in plant development besides soil type. Nevertheless, this brief inference relating plant to human development is a good analogy.
No gene can express itself unless a suitable environment exists to allow its expression. Genes cannot and do not act independently of the milieu in which they function. The environment is therefore the ultimate determinant of gene expression and degree of expression.
Identical twins, even though they have identical DNA, develop different brains. Cloned plants, even though they have identical DNA, develop root structures different from one other. The function of the roots of each plant is similar, yet the pattern of the roots is obviously different; the same can be stated about the brains of twins. Many environmental factors result in changes in gene expression, even in clones and identical twins.
The gene must be resourceful and flexible enough to turn off or to trigger other genetic sequences, should existing circumstances not permit it to express itself. Some genes will not even turn on unless circumstances become harsh enough. The DNA must produce a phenotype capable of adapting to existing and sometime varying circumstances. Natural selection acts not on "genes" but on phenotypes, which are the product of necessary genetic processes in suitable milieus.
There is no such thing as gene and environmental cooperation where gene functioning is concerned. The environment doesn't cooperate or change to suit the needs of the gene. But genes, in a suitable environment, have developed organs, such as glands, to help change their environment. And, of course, phenotypes, the products of genes, have developed the ability to change their environmental circumstances. A gopher burrow is just one example.
Thus it can be stated that all organism behavior is genetically determined (after all, without a gene, there would be no organism); while at the same time, one must lay emphasis on the fact that past and present environmental circumstances have determined the behavior and function of the genes. What does this mean? This means that the individual is a product of his genes' developmental strategies as permitted by past and present environmental circumstances.
Since all behavior is genetically determined to the extent of the individual's ability to adapt and function, and since differences in behavior are noted in individuals with similar genetic structures, then one must seriously consider the probability of the difference arising as a result of differences in environmental circumstances. Therefore, when the behavioral differences of a similar stock is noted, genetic determination of behavior need not even be taken into consideration. Slight genetic variance or genetic drift just doesn't account for the differences in behavior usually observed. Only the differences in environmental circumstances, to which each organism has been exposed as individuals, can explain such behavioral differences.
It seems most people automatically assume that individuals raised in the same household or similar households have the same or similar environments. Nothing can be further from the truth. So since there is confusion over gene-environment interaction, and since there is much confusion as to precisely what an "environment" is that each individual is exposed to (resulting in personality differences), the whole matter needs to be reiterated and clarified:
The behavior of all organisms is determined by the organism's genetic endowment, which is traceable to the evolutionary history of his (or her) species, and by the environmental circumstances to which he (or she) has been personally exposed (as an individual). Twins are more or less clones in the sense that they have identical genes. But twins do not have identical personal experiences from the cradle to the grave. And these personal experiences are the environmental circumstances that make twins different.
Abigail and Brittany Hensel are twins whose bodies didn't separate entirely in their mother's womb. As a consequence, they were born with one body. They sort of look like a person with two heads. But Abby controls one arm and leg, and Brittany controls the other arm and leg. Yet, even though they are two individuals who share the same body, they had and have different environmental circumstances. For example, a caretaker of the twins may have scolded one of the twins for not cooperating with her sister. Or maybe when the children were learning to walk, something happened to cause one child to take a step before the other child. Some environmental circumstance caused one child to become dominate over the other child. Now one leads and the other follows, so to speak. Of course, Abby and Brittany couldn't function as they now do if this process had never happened. Nevertheless, the circumstances Abby subjects Brittany to are not the same circumstances that Brittany subjects Abby to. And the way others interact with Abby is not precisely the way they interact with Brittany.
Naturally, one other component to take into consideration is the fact that the human is a herd animal. We have instinctive mechanisms that stimulate us into conforming with the expectations of our herd (peer group). Therefore, the adolescent is correct (in a roundabout way) when blaming his (or her) peer group for personal behavior. (And yes, an adolescent just might jump off a cliff if "all the other kids were doing it." However, it would really be his (or her) herd instinct that would be directly to blame.) Now combine this fact with the fact that individuals in our country and in this age are taught to express individuality (possibly to discourage the family/herd instinct (fascist/socialistic tendencies) within the individual). As a result, Abby and Brittany are peer pressured into having dissimilar likes and dislikes. And as a consequence, Brittany may like the color red, resulting in Abby liking a different color. Nevertheless, the likes and dislikes that are common to their peer group (herd) are the likes and dislikes that would be common to Abby and Brittany. For example, neither one is unpatriotic (not in public anyway) because their peer group expresses patriotism.
Alfred Russel Wallace, the co-discoverer of the evolutionary theory, unlike Darwin, assumed that the human brain was far too complicated to have been produced by evolution. We now know that Wallace was wrong. Nevertheless, the very fact that Wallace, in his ignorance and confusion, attributed the complexities of the brain to paranormal causes and effects should be a lesson to us all. In fact, when we study the history of human knowledge and understanding from the most remote time till now, and from the most primitive society to the most modern, we notice that humans have always had the tendency of inventing paranormal tales to explain away overly complex phenomena and the great unknown. So naturalism, as put forth by Naturalism Organization, is the only solution to this naive and superstitious tendency.
We of course realize that organism behavior cannot occur without a suitable environment. And we have studied organisms enough to realize that neither organism development nor organism behavior are the result of preternatural forces. Therefore, we know all organism behavior--including the human organism--is the product of natural causes and effects. And as a logical conclusion, we also realize that a naturalist's stance is required to overcome the present illusions concerning human behavior and the unknown.
We speak of individuals being free as the wind. And as long as we remember that the wind and the behavior of the wind are both consequences of natural causes and effects, then "free as the wind" serves as the perfect analogy for the human being.
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