[geographomics]

Most of the commentary here so far is really quite tangential to the actual research done. Everyone commenting on this article should make sure they've read the study first, with particular attention to the 'Limitations' section on page 11: http://m.jmq.sagepub.com/content/early/2016/02/25/1077699016...

One other feature of the study that limits its wider applicability is that it is entirely US-centric. It would be interesting to read follow-up work on samples taken from other cultures and countries.