For those that haven't heard it yet, here is a youtube link:
https://www.youtube.com/watch?v=03CKUT8Y2as
And I did some digging. As we all know by now it's from the documentary in 2016 about elephants in Africa. More specifically this documentary:
https://vimeo.com/168811238
At the beginning of the video is a short clip of a studio cut.