Season 2010 National Geographic , 2010 Season 2011 National Geographic , 2011 Season 2012 National Geographic , 2012 Season 2013 National Geographic , 2013 Season 2014 National Geographic , 2014 Season 2015 National Geographic , 2015 Season 2016 National Geographic , 2016 Season 2017 National Geographic , 2017 Season 2018 National Geographic , 2018 Season 2020 National Geographic , 2020 Season 2022 National Geographic , 2022