Original article from 2007: http://www.sciencedirect.com/science/article/pii/S002251930700416X http://www.sciencedirect.com/science/article/pii/S0022519307...

Original article from 2007: http://www.sciencedirect.com/science/article/pii/S002251930700416X http://www.sciencedirect.com/science/article/pii/S0022519307... and more recent one: http://onlinelibrary.wiley.com/doi/10.1111/j.1420-9101.2009.01809.x/abstract http://onlinelibrary.wiley.com/doi/10.1111/j.1420-9101.2009.... via reddit: http://www.reddit.com/r/science/comments/1xkm1x/scientists_finally_discover_the_function_of_the/ http://www.reddit.com/r/science/comments/1xkm1x/scientists_f...