Twins Yield Clues to Loves's Shared Origins

Article excerpt

Some people find enduring love wit one romantic partner; others conduct one affair after another, or several at once, with gusto. Some get feverish and hysterical with love; others move methodically from extended friendship to romantic involvement.

The first twin study of attitudes about love now indicates that siblings' share observations of their parents' relationship and cultural practices, as well a parent and peer experiences unique to each sibling, largely shape a person's romantic style. Genes, however, play virtually no part in producing individual differences in the approach to ardor, report Niels G. Waller and Phillip R. Shaver, both psychologists at the University of California, Davis.

"Humans might be wired to pay particular attention to the relational styles they're exposed to beginning early on," Waller contends. "Learned orientations to love may subsequently play out in romantic relationships."

Previous twin studies have found consistently large effects of genes and unique environmental influences in shaping an individual's intelligence, emotional dispositions, and personality traits (SN: 12/7/91, p.376). Common family experiences of siblings make little impact in these areas, investigators have found.

Unlike individual capacities that reflect inherited variations in brain function, romantic attitudes focus on social relations, Waller asserts. Thus, for the first time in a twin study, siblings' shared environments loom large.

Waller and Shaver studied 338 female and 107 male twin pairs contacted through the California Twin Registry identical twins (who share all the same genes) comprised about three-quarters of the sample; fraternal twins (who share, on average, half the same genes) made up the remainder. Participants averaged about 36 years old. The spouses of 172 of the twins also took part in the study

As part of a battery of personality and attitude tests, twins and spouses completed a survey that measures the degree of adherence to six "love styles. …