Hereditariness of behavioural characteristics
Various research centres are studying identical twins in order to discover the “heritability” of behavioural characteristics – that is the degree to which a trait is due to genes (“nature”) instead of the environment/. They have reached some startling conclusions. One study found, for example, that optimism and pessimism are both very much influenced by genes, but only optimism is affected by environment as well. According to another study, genes influence our coffee consumption, but not consumption of tea. Anxiety seems to be 40 to 50 percent heritable. Another study tells us that happiness does not depend much on money or love or professional success; instead, it is 80 percent heritable! Among the traits that appear to be largely heritable are shyness, attraction to danger (thrill seeking),choice of career and religious belief.
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