Alligators Renew Freaky Behavior Of Freezing Themselves In NC Swamp With Noses Out, The Charlotte Observer, 24 January 2019

Alligators in one eastern North Carolina swamp have proven it was no fluke last winter, when they survived a cold snap by freezing themselves in place with their noses above the ice.

Experts say the adaptation disproves the long standing belief that alligators are prevented from migrating north due to cold temperatures.

Howard says the alligators seem to sense when the water is at the freezing point and they respond by poking their nose above the surface “at just the right moment.”

Once frozen, they enter “a state of brumation, like hibernating,” until the water thaws.

The alligators that froze last year in the park thawed out a few days later with no apparent injuries, he said.

Scientists Say These ‘Frozen’ Alligators Aren’t Dead. They’re Still Creeping People Out, Washington Post, 25 January 2019

When it starts getting cold, the alligators submerge most of their bodies in the shallow water, then stick their noses up in the air in anticipation of the freeze ahead, creating a little hole to breathe through. Once the water freezes, the ice sticks to their snouts, locking the gator-cicles in place while their bodies dangle below the surface.

The behavior, he said, is likely not something the alligators learned by practicing but, rather, is instinctual, something developed over time through natural selection. … “If the alligator species has been living in cold temperatures for a long enough time, then the ones who were able to do this are the ones that would be able to survive and reproduce.”

When the alligators go under, Rosenblatt said, they enter what’s called “brumation” — like hibernation but for the coldblooded — and their bodies almost entirely shut down. All they need to do is breathe. … “They basically shut down their metabolism. They don’t need to eat because they’re not burning a lot of energy,” Rosenblatt said. “They slow down their heart rate, their digestive system, and they just sit there and wait out the cold weather. It’s a pretty amazing adaptation.”

Humans may not be able to go into a state of brumation, or torpor, or hibernation, to weather the cold, but there’s one thing we can do that these animals cannot: control fire. Not only has it kept us warm, but it has allowed us to cook our food, which, according to Richard Wrangham in his book, Catching Fire made us the humans we are today:

Richard Wrangham makes the claim that learning to cook food was the hinge on which human evolution turned. Eating cooked food, he argues, enabled us to evolve our large brains, and cooking itself became a primary focus of human social activity — in short, cooking made us the social, intelligent, and sexual species we are today.

I wonder how we would have evolved if we hadn’t learned to control fire. Maybe we’d also have developed some kind of metabolism shut-down, some kind of torpor.