I believe the paper discussed is: http://www.pnas.org/content/early/2009/01/12/0810907106.abstract?sid=fc8f7e4b-b7ff-48d0-8ec1-64d6cd40b248 http://www.pnas.org/

I believe the paper discussed is: http://www.pnas.org/content/early/2009/01/12/0810907106.abstract?sid=fc8f7e4b-b7ff-48d0-8ec1-64d6cd40b248 http://www.pnas.org/content/early/2009/01/12/0810907106.abst... There is this related paper which looks interesting: http://www.pnas.org/content/105/16/6167 http://www.pnas.org/content/105/16/6167