Season 1 National Geographic , 2006 - 2007 Watch now Season 2 National Geographic , 2007 - 2008 Watch now Season 3 National Geographic , 2009 - 2010 Watch now Season 4 National Geographic , 2011 Watch now Season 5 National Geographic , 2011 - 2012 Watch now Season 6 National Geographic , 2012 Watch now Season 7 National Geographic , 2012 - 2013 Season 8 National Geographic , 2012 - 2013
, 2006 - 2007
