How many fields other than human evolution can tolerate the following level of vagueness with no alarms ringing?:

In “Out-of-Africa migration selected novelty-seeking genes” (New Scientist, 06 May 2011), Aria Pearson tells us, “AS HUMANS migrated out of Africa around 50,000 years ago and moved across the planet, evolution may have latched onto a gene linked to risk-taking and adventurousness.” Once treated skeptically, the idea “stands up to rigorous analysis,” due to minor differences in gene frequencies:

The study suggests that some small portion of the behaviours that characterise populations may be down to genetics, and that cultural actions like mass migration can modify our genes, says Matthews.

Marcus Munafò, a biological psychologist at the University of Bristol, UK, cautions that variations in the DRD4 gene are numerous and complex, making its exact behavioural effects hard to pin down. But he agrees that it is likely that some differences in behaviour have been generated by genetic selection.

If a characteristic is usefully identified as genetic, shouldn’t it offer a stronger signal than this? And shouldn’t analysis be more rigorous than this?

How much have we learned by talking about these vague possible effects of genes, compared to simply inferring – using no information about genetics at all – that people who, when they face problems, choose to up stakes and set off for parts unknown are by definition more adventurous than most of us?

And if someone who does this turns out to have the wrong alleles, then he isn’t wrong, genetics is. Or maybe genetics is right but this isn't genetics.

Denyse O'Leary is co-author of The Spiritual Brain.

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