Wow: 13-lined ground squirrels endures winter by packing fat *into* heart

Denver 2009 - Thirteen-Lined Ground Squirrel 01

A thirteen-lined ground squirrel going on a fat binge. Photo

The editorial staff of Squirrels, Squirrels, Squirrels has visited Minnesota in December. So, we’re only partially surprised to read the findings of a cool study out of Duluth, which examines how the 13-lined ground squirrel hibernates without becoming a completely frozen solid squirrel-sicle.

(I mean, these cute critters of course have fur and can huddle together in their little hidey-holes, but still, when it’s -40 outside, …it seems like only White Walkers should be alive and in the mood for napping, while everyone else gets on an RV and heads to South Padre Island.)

Anyway, how do they do it? It takes extreme metabolism to counter the extreme weather. Precisely, they literally store fat in their hearts, and then slowly burn off that fat all winter long. Yes, it sounds counter-intuitive to long-term survival (equivalent to a human eating a triple-bacon cheeseburger for every meal), but the long starvation following their autumn pig-out creates a metabolic state known as “ketosis,” and that apparently brings them good tidings, cheer and above-average longevity compared to similar non-hibernating species.

Lest you wonder why the hell anyone cares, Katharine Gammon, writing in Chemical & Engineering News, clears that right up for you:

“Eventually, this knowledge may help researchers develop ways to protect heart tissue from the harmful effects of free radicals that are produced after a heart attack.”

So there. Squirrel research saving lives.