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:
“What strikes many twin researchers now is not how much identical twins are alike, but rather how different they are, given the same genetic makeup....Multiples don’t walk around in lockstep, talking in unison, thinking identical thoughts. The bond for normal twins, whether they are identical or fraternal, is based on how they, as individuals who are keenly aware of the differences between them, learn to relate to one another.”
—Pamela Patrick Novotny (20th century)
“Old-fashioned determinism was what we may call hard determinism. It did not shrink from such words as fatality, bondage of the will, necessitation, and the like. Nowadays, we have a soft determinism which abhors harsh words, and, repudiating fatality, necessity, and even predetermination, says that its real name is freedom; for freedom is only necessity understood, and bondage to the highest is identical with true freedom.”
—William James (1842–1910)