I hesitate to refer to the splendid "The Woman Who Loves Giraffes" as a nature documentary, because of everything that take-your-medicine-it's-good-for-you term seems to imply: dull talking heads, stately panoramas and whispered narration of animals doing the boring stuff the filmmakers manage to catch on camera.

Obviously, the above doesn't describe every nature documentary. There are plenty of classics, including "Microcosmos" and "The Living Sea," but "The Woman Who Loves Giraffes" has so much personality, humor and warmth that it feels like it belongs in its own category — in part because it's more about the woman than the giraffes. (It's available for streaming in an arrangement that benefits both the filmmakers and the MSP Film Society.)

She's 87-year-old Canadian naturalist Anna Innis Dagg and she's basically the Jane Goodall of giraffes, although if you want to be picky about it, Dagg reached Africa a few years before Goodall did. Passionate, funny and modest, Dagg is the sort of "character" documentarians dream of finding. Her story is filled with the twists and turns of a thriller because, although her trailblazing research on giraffes and their behavior dates to the 1950s, she did not get credit for it. You'll never guess why.

Oh, you guessed.

"She was unfairly judged and I think it destroyed her career," says a colleague, interviewed in the present day, of Dagg being denied tenure in 1972 by the University of Guelph.

"I'd done everything I needed to do and they just said, 'Well, you're a woman,' " explains Dagg, still fighting off tears at the 50-year-old memory. "It just meant the end of everything I had hoped for."

Dagg sidelined her research, raised a family and accomplished other things, but her optimism buoys this crowd-pleasing movie as it finds a happy ending, with an assist from Dagg's adult daughter, who was astonished to learn how accomplished her mom was. Dagg's books are rediscovered, she goes back to Africa to resume her research, and a new generation of naturalists gets to tell her how much she has meant to them.

"I was the little girl that woman was a hero for," says San Diego Zoo giraffe keeper Amy Phelps.

"The Woman Who Loves Giraffes" has it all: misogyny, racism (Dagg first visited South Africa under apartheid), even romance. Most of all, it has the feisty Dagg, who has shifted gears several times in her life but who always fought for what she believed in. ("It felt good to complain," she says simply, after bumping up against another glass ceiling.)

Director Alison Reid begins and ends the film with Dagg's return to Africa after decades away. Reid blends archival film from the 1950s with contemporary footage to show Dagg visiting the same places, almost as if she's time-traveling from the 21st century back to the 20th. And it's not just home movies or the researchers she inspired that connect the octogenarian's past and present.

As Dagg rides through the wilds of South Africa in a jeep, a guide points out that the animals she is meeting are actually old friends: the descendants of the giraffes she studied 60 years earlier.