Heat: v6

GOOSEBUMPS: Goosebumps are caused by tightened Maximus muscles at the base of the tiny hairs on your skin.

GOOSEBUMPS: When the tiny muscles contract, they pull the hairs they’re attached to a 45º angle.

GOOSEBUMPS: As the muscles are tightened, the brain continues to send messages to the arrector pili muscles.

GOOSEBUMPS: Why does your body raise its hairs? It helps with something called mechano-regulation.

GOOSEBUMPS:  If you hike through a forest on a cold day,  stay away from the cold wind as much as possible. Take shelter in a grove of trees. Here the air is still and much warmer. Cold moving air can take away heat from your body’s core temperature. The trees can help prevent this by acting as a barrier between you and the cold wind.

GOOSEBUMPS: When you get goosebumps, it’s like you’re making a tiny forest of hair on your skin. The standing hairs trap a little invisible blanket of air around your exposed skin. This prevents some heat loss that you’d have if you were bare-skinned with no protection from the cold air always brushing you.

 GOOSEBUMPS: When cats come home on a really cold night after roaming the neighborhood, they may look like big puff balls. The flexor pili muscles around hundreds of thousands of hairs make up the cat’s fur stand straight up to create big blankets of warm air around them.

ELLIE’S WILD EARS: A car stays cool thanks to its radiator. Coolant flows through the engine, absorbing heat as it goes. The coolant then flows into the radiator where airflow draws the heat out of the coolant. After this, the newly-cooled fluid gets pumped back into the engine and the cycle continues.

ELLIE’S WILD EARS: An elephant cools itself in a very similar way. Their huge ears contain thousands of miles of blood capillaries. When the elephant’s brain detects a temperature rise, even one as small as a millionth of a degree, it kicks into action.

ELLIE’S WILD EARS: When an elephant gets too hot, blood vessels throughout elephant ears widen, allowing for increased blood flow. The blood then pours into the ears, carrying the heat from inside the body. As the blood flows through the thin ears, the heat goes into the air, cooling the blood. The cooled blood then flows back into the body, ready to absorb more heat!