Surviving a Canadian winter can be a struggle — even with modern heating. But Ontario wildlife have been enduring the cold for thousands of years. If you’re fond of winter walks through forests in Ontario — and indeed most of Canada — odds are you’ve tread on a frozen frog. They hide under leaf litter or just a few centimetres underground, where the temperature hovers a few degrees below zero. And then they freeze. But then comes spring, and they start to thaw — from the inside out. …Ontario’s turtles spend the winter in frozen-over ponds, unable to surface for air… Instead, they absorb oxygen from the water through several surfaces, including the cloaca — a specialized tissue located under their tails. This process is known as cloacal respiration. So if we’re flexible with terminology, we can indeed say that when turtles take up oxygen through their cloaca, they are breathing through their butts.