Genetic Determinism
While there are many examples of animals that display certain well-defined behaviour that is genetically programmed, these examples have been extrapolated to a popular misconception that all patterns of behaviour, and more generally the phenotype, are rigidly genetically determined. There is good evidence that some basic aspects of human behaviour, such as circadian rhythms are genetically-based, but it is clear that many other aspects are not.
In the first place, much phenotypic variability does not stem from genetics. For example:
- Epigenetic inheritance. In the widest definition this includes all biological inheritance mechanisms that do not change or involve the genome. In a narrower definition it excludes biological phenomena such as the effects of prions and maternal antibodies which are also inherited and have clear survival implications.
- Learning from experience. This is obviously a very important feature of humans, but there is considerable evidence of learned behaviour in other animal species (vertebrates and invertebrates). There are even reports of learned behaviour in Drosophila larvae.
Read more about this topic: Common Misunderstandings Of Genetics
Famous quotes containing the words genetic and/or determinism:
“Nature, we are starting to realize, is every bit as important as nurture. Genetic influences, brain chemistry, and neurological development contribute strongly to who we are as children and what we become as adults. For example, tendencies to excessive worrying or timidity, leadership qualities, risk taking, obedience to authority, all appear to have a constitutional aspect.”
—Stanley Turecki (20th century)
“Man is a masterpiece of creation if for no other reason than that, all the weight of evidence for determinism notwithstanding, he believes he has free will.”
—G.C. (Georg Christoph)