Throw us into the wild, and the core of survival is nothing more than clothing, food, shelter, and transportation.
In the far, cold north, the most extreme environment on Earth, the Arctic fox (Vulpes lagopus) is a good interpretation of the key to the survival course in the wild with its extraordinary adaptability. In terms of dressing, eating, etc., extraordinary adaptability has evolved.
dressing
The arctic fox is common in the Arctic tundra biome, and it is ideal for living in cold environments. It depends on its thick, dense, warm multi-layered fur.
This is a set of fur that has basically no dead ends - the Arctic fox is the only canine whose feet are covered with fur. However, there is a bigger secret hidden beneath the fur: one way the Arctic fox regulates its body temperature is by harnessing countercurrent heat exchange in the blood of its legs, and when it stands on cold ice and snow, it can always keep the temperature of its feet above freezing (−1 °C) without losing mobility or feeling pain.
Polar Biology once pointed out that arctic foxes must endure temperature differences of up to 90–100 °C between the external environment and their internal core temperature. Arctic foxes don't even shiver until the outside temperature drops to −70 °C.
Most of us know that arctic foxes change their snow-white fur in winter, but in reality, there are two genetically different coat color variants in arctic foxes: white and blue.
The blue variant is dark blue, brown, or gray all year round. Although blue alleles are dominant over white alleles, the vast majority of Arctic fox populations are white variants.
The white variant lives mainly inland, blending in with the snowy tundra, while the blue variant occupies the coast because its dark color blends in with the cliffs and rocks. The thing about the blue arctic fox is very interesting, dig a hole first, and talk about it in detail next time.
diet
Arctic foxes are not picky eaters, they prey on all creatures smaller than themselves, such as lemmings, voles, ringed seal cubs, fish, waterfowl, and seabirds. Carrion, berries, seaweed, as well as insects and other small invertebrates will not be spared.
The tundra has long winters and food is extremely scarce. Arctic foxes do not hibernate, which means they eat all year round. An Arctic fox weighing an average of 3.5 kg needs 471 kJ/day to survive in winter.
Arctic foxes that will cage food and have enough stocks to survive. In this regard, in some regions such as Russia and Canada, the life and death of Arctic foxes and their theft and cage skills are closely related.
Arctic foxes in these areas feed mainly on lemmings (Dicrostonyx vinogradovi), but lemmings are seasonal and periodic (3 to 4 year cycles), and resourceful Arctic foxes learn to grasp the opportunity each spring.
Every spring, thousands of large geese, Chen caerulescens, land on the island to lay eggs (up to six eggs per pair) in simple nests dug out of the tundra.
The arctic fox set its sights on the goose eggs. Although the snow goose will fiercely resist, the fox is cunning and persistent. There may be up to a dozen hungry pups to feed in the nest, and a fox couple will spend nearly 8 hours a day roaming the snow geese colony, looking for an opportunity to strike.
On average, Arctic foxes steal up to 40 pebbles a day – anything they and the cubs don't eat immediately is hidden and eaten over the next days, weeks, months.
Remember the cartoon "Eggs" you watched as a child? That's pretty much what it means.
Arctic foxes steal eggs from snow geese and store 80-97% of them. The researchers collected evidence from their feces that suggests that a large portion of these eggs are stored even into the winter. Isotope analysis shows that the eggs are still edible after one year.
This fresh snow goose egg has about 816 kJ in calories, and the eggs that are buried and stored, the eggs lose only about 8% of their dry weight after 60 days of underground storage, and their metabolic energy drops by only 11%, which is a major advantage of the tundra tundra world.
Write at the end
Foxes in Russia and Canada, thousands of miles apart, how many eggs they can steal and save in the spring is the key to their livelihood. And what about snow geese?
Nature seems to have achieved a sustainable balance, allowing fox cubs to be fed and flocks of snow geese flying through the air.
Author thanks for your attention (- _-)