The Errol Morris documentary "Fast, Cheap & Out of Control" has a segment on mole rats [0].
I think that movie would appeal to a lot of HN members -- it's broadly about people who obsessively pursue some interesting corner of skill or knowledge, and how that makes the world a richer place. Kind of like the "Fred Dibnah, Stepplejack" series that I learned about on HN ([1], and I know it made HN about 7 years ago as well).