Thursday, April 22, 2010

The debate on "Nature vs. Nurture"...

...continues:

In recent years, researchers have posed a series of hot-button political questions to pairs of identical and fraternal twins. The first major study (PDF) of this kind, published in 2005, asked twins for their positions on issues like foreign aid, death penalty, and abortion. Responses from identical twins were more correlated than those from fraternal twins on every issue. School prayer and property taxes were singled out by the researchers as being the most strongly influenced by genetics. When responses were aggregated and reduced to either a conservative or liberal worldview, the authors concluded that genetics could explain 43 percent of someone's political outlook.

While most observers agree that identical twins are more likely to share a political identity, many have contested the notion that genetics are the cause. Studies of this kind are based on the assumption that monozygotic (identical) twins share the same genes and the same environment, while dizygotic (fraternal) twins have only the latter in common. But identical twins are not always treated the same way as dizygotic twins. They may be dressed the same way by their parents, made to sleep in the same bedroom, or given rhyming names. They're also likely to spend more time together and to be confused for each other by family and friends. At the same time, monozygotic twins aren't really genetically identical (PDF) in the first place. So their convergent worldviews might be due to environmental, and not genetic, factors.

1 comment:

Unknown said...

Mike, I didn't even know you knew the words dizygotic and monozygotic. I thought for sure you slept thru biology class. Next you will be throwing out words like myosis and mytosis or maybe exothermic and endothermic? You have become a true renaissance man.