a BBC Studios Natural History Unit production ; a co-production with BBC America, Tencent, WDR, France Televisions and CCTV9 ; a BBC Open University partnership ; executive producer, James Honeyborne ; series producer, Mark Brownlow ; producers, Miles Barton, Orla Doherty, Kathryn Jeffs, Will Ridgeon, John Ruthven, Jonathan Smith
a Frontline co-production with Hedrick Smith Productions ; WGBH Educational Foundation ; Frontline executive producer, David Fanning ; senior producer, Hedrick Smith ; producer, Marc Shaffer ; written by Hedrick Smith and Rick Young ; director, Rick Young