Polar bears are classic examples of “charismatic megafauna,” finishing a solid 8th in a 2018 survey of the most charismatic species on earth. (The Top 20 ranking includes zero birds, and 4 of the top 7 are murderous cats, which reveals more about humans than it does about other animals.) I certainly agree that they are charismatic, having watched them perform at a zoo many years ago, though I admit my fanhood was diminished by watching them hunt baby belugas in the not-very-deep blue sea.*
One thing that stands out is that fur. It’s not actually white—it’s hollow and thereby provides insulation. Maybe you knew that, but did you know that polar bear fur doesn’t accumulate ice? It should (water and cold and all) but it doesn’t, and a recent paper in Science Advances explains why: the fur contains a lot of greasy secretions. NPR already did a great job on the story, in which the lead author connects her team’s findings to people and the past: “We didn’t discover it,” she says. “It’s been known to Arctic people for centuries.” Their abstract notes that the work “builds on Inuit knowledge of natural anti-icing materials.”
In that vein, here is some nice writing in the Introduction, that caught my eye for its opening of a window to the past:
…polar bears are known to slide on snow and ice (Fig. 1A). An early account of this behavior is given by the Inuk hunter and artist Jakob Danielsen (1888 to 1938). He writes: The (polar bear) mother plays a lot with her young. We see in the mountains that they have made slides on the snow slopes down which they go on their tail all in the same track (25) (p. 317).
See bottom for a picture of a bear doing that! It’s Figure 1 of the paper.
*Listen to “Baby Beluga” by Raffi if my phrasing seems weird to you.
Anti-icing properties of polar bear fur
in Science Advances, 29 January 2025
From the lab/group of Bodil Holst.
Snippet by Stephen Matheson.
