http://www.bbc.co.uk/news/science-environment-31905764 http://www.bbc.co.uk/news/science-environment-31905764 linked paper: http://www.nature.com/articles/natu

http://www.bbc.co.uk/news/science-environment-31905764 http://www.bbc.co.uk/news/science-environment-31905764 linked paper: http://www.nature.com/articles/nature14230.epdf?referrer_access_token=FWSH2OxFv3gf9b2FDPFRTtRgN0jAjWel9jnR3ZoTv0MiE0_B2kFTYAb64eH_EPxJeiJzg7Mfl6MEBC6p_EUzUhn20X4WGsMhORPh_wQWF0XWfuvis22UqrLNVuhlijqXTxOXx-26amOZUjUE9AICb6b0pntMdyrodOCNexNDOMxQRYdelduIrY7VrvsjQSAtiFToY0MWnW3lnB5Fewt8Dm3UNcXCr3OE1od7Uvr7Q3o%3D&tracking_referrer=www.bbc.co.uk http://www.nature.com/articles/nature14230.epdf?referrer_acc... The paper is pretty good. The truth of it is they make groupings based on correlations and name the correlations based on where it is most common / convenient