The deceptively cute Gray Jay is one of the most intrepid birds in North America, living in northern forests year-round and rearing chicks in the dark of winter. Highly curious and always on the lookout for food, Gray Jays eat just about anything, from berries to small animals. They may even land on your hand to grab a raisin or peanut.
A thermal insulator is something that prevents heat from moving from one place to another. There are 3 main ways that heat can travel: convection, conduction, and radiation. Typically the phrase 'thermal insulator' refers to a material that blocks conduction.
In other words, thermal insulation can keep an enclosed area such as a building warm, or it can keep the inside of a container cold. Heat is transferred by from one material to another by conduction, convection and/or radiation. Insulators are used to minimize that transfer of heat energy.