Blood vessels in the skin constrict, conserving heat.
According to Epstein, there's an evolutionary explanation for all this: hot and dry environments favor very thin, long-limbed frames, which are easy to cool, just as cold climates favor thick, squat bodies, which are better at conserving heat.
Large feathers have often been used in fans, thereby providing an example of an object put to opposite uses for cooling as well as for conserving heat.
Conversely, cold causes contraction of the vessels and initiates shivering, thereby conserving heat in the first instance and generating it in the second.
In very cold weather, the outer pipes nearer to the skin's surface narrow, pushing the blood deeper to warmer more critical vital organs, conserving heat and pressure.
I clambered over black, ropy lava and was struck by the ability of life to thrive in this stark setting: between clumps of yellow-tinged lava cactus, hundreds of plump marine iguanas — the world's only seagoing lizards — were heaped on top of one another, conserving heat.
The Bowhead has the most highly developed blubber layer among whales (a foot thick), and a complex blood circulatory mechanism for conserving heat.
Thermal wear (even ones that are non-athletic) are also very good at conserving heat.
However, I recall that the decision later was amended to push the date back to conserve heating fuel.
