Love links
Romantic behaviour has more to do with environmental influences than heredity, according to a study by behavioural geneticists at the University of California, Davis, US. The finding comes as a surprise to psychologists who often cite the heritability of sexual promiscuity (Science Vol 266, No 5183).
Niels G Waller and Phillip R Shaver conducted personality tests among 345 pairs of identical twins, 100 pairs of fraternal twins and 172 spouses of twins. If a particular character is inherited, identical twins -- who have all their genes common -- will show about twice as much concordance as fraternals. The scientists found that genes did not influence the love style of the twins while other personality traits like intelligence had about 50 per cent genetic influence.