From hibernating to minimize energy consumption to storing energy and food, all living species have a way of adapting when food becomes scarce and habitats freeze.
When winter comes, plants stop growing and hibernate to conserve energy. Water scarcity can become the biggest problem at this point because if the ground freezes, the roots can’t have liquid to suck up. And so conifers create a waxy coating on the outside of their leaves to limit water loss through evaporation.
Deciduous species must shed their leaves entirely, or else they will lose water through such flat, broad leaf surfaces. They protect cells from freezing by transporting water from tissues to spaces outside the cells. Some plants have the ability to produce sugar in winter to increase resistance to cold.
The harsh winter also puts pressure on the animals. Not only are food sources becoming scarce, but shorter daylight hours mean less time to forage. Many species adapt by stocking up on food before winter arrives. Like this pika rabbit, a mammal-like rodent that lives in the mountains of North America, Asia, and parts of Eastern Europe, it survives by hoarding dry food in its burrows.
Some animals prepare for winter by growing thick fur or storing thick fat under their skin. The arctic fox even changes its coat color, changing its darker summer coat to a white one. Thanks to that, it easily hides in the ice and snow to hunt in the winter. Its toned body and thick coat of nails also help it retain heat better.
Many mammals, such as marmot squirrels, respond to cold by hibernating. They lie dormant deep in a protected burrow. In this deep state of lethargy, they lower their heart rate and breathing rate to extremely low levels, and lower their body temperature to conserve energy. Bears also hibernate, although they have a very thick coat in the winter. But unlike marmot squirrels, bears keep their body temperature fairly constant during this time.
Bears have thick fur to keep their bodies warm, but what about insects? With their bodies composed mainly of water, they need to avoid freezing to survive. Some insects do this very well by producing antifreeze that prevents ice crystals from growing in their cells. One study found that fire beetles can withstand temperatures as low as -30 degrees Celsius.
Antarctic moss also evolved to withstand sub-zero temperatures. This vegetation lives close to the soil to protect itself from fierce winds and can live without water for long periods of time when liquid trapped in the ice. The moss beds hibernate for months when the surroundings are too dry, cold or dark, then quickly come back to life in the spring when the ice melts.
Painted turtles spend the winter at the bottom of ponds, even on frozen water. This native North American animal slows down its metabolism by up to 90% in order for the body to survive without additional food. Normally, they come to the surface to breathe, but during the winter they absorb enough oxygen through the surface of their bodies without using their lungs. They can even convert their metabolism to a form that doesn’t require oxygen.