Season 1 National Geographic Watch now Season 2005 National Geographic , 2005 Season 2006 National Geographic , 2006 Season 2007 National Geographic , 2007 Season 2008 National Geographic , 2008 Season 2009 National Geographic , 2009 Season 2010 National Geographic , 2010 Season 2011 National Geographic , 2012 Season 2012 National Geographic , 2012