Soldiers walk past part of a message written in blood at the site of a massacre at a ranch in northern Guatemala on May 16. The message is a warning to Otto Salguero — the owner of the ranch, according to local media. Guatemalan authorities blame the killings on the Mexican drug cartel Los Zetas.
A study published in the journal Science last December suggested that a bacterium found in California's Mono Lake was able to substitute arsenic for phosphorous. But that conclusion has many critics.
Miss Bliss 55 via Flickr