What two distinct layers comprise the dense double coat optimized for thermal regulation in freezing Yakutian conditions?

Answer

A thick, soft undercoat and a coarser, weather-resistant outer layer

The defining feature enabling the Laika's survival in severe cold is its dense double coat, which is structurally optimized for maximum thermal regulation. This coat is composed of two separate layers. The first is a thick, soft undercoat whose primary function is to trap warm air close to the skin, creating a layer of insulation. The second layer is the coarser, weather-resistant outer coat, which serves the crucial purpose of repelling environmental elements such as snow and ice, thereby keeping the inner layers dry and effective in subzero temperatures.

What two distinct layers comprise the dense double coat optimized for thermal regulation in freezing Yakutian conditions?
weatherDogtoleranceheatYakutian Laika