Pretty much the entire second half of the article addresses this directly. Or find a way to watch that segment of the documentary. Those few lines of the narra

Pretty much the entire second half of the article addresses this directly. Or find a way to watch that segment of the documentary. Those few lines of the narration don't really capture the narrative of the visual story-telling. (Though it was somewhat sickening to watch even before we knew the filmmakers were torturing and killing the lemmings rather than just observing them.)