In a message dated 11/19/2002 6:57:09 AM Mountain Standard Time, NJ-MEMORIES-D-request@rootsweb.com writes: > Anyone out there know what they are, and why > we get them when were cold? I bet Doris knows. > Yup. Each of the hairs on our bodies has a little involuntary muscle attached to it; it's called a pilomotor muscle or a piloerector. What it does is to make the hair stand up instead of lying flat when it is working. Those muscles are activated by cold and also by adrenalin. In a low-temperature situation, erect hair (like the fluffed-up down in a winter jacket) traps more air than when it is flat, hence adding insulation capability. In a "fight-or-flight" situation, when our bodies release adrenalin, erect hair makes mammals look larger and hence scarier to enemies (what does your cat look like when he confronts a strange dog?). It also conserves body heat and hence energy, giving the possessor of that hair more reserves for either fighting or running away. The reason for the "goose bumps" is that the piloerector muscles are attached to the lower levels of the skin (that's where they get their leverage from); and when they contract, they pull in the skin around them, hence forcing the upper levels upward in the characteristic bump. That's why we speak of scary stories "giving us gooseflesh" or "making our hair stand on end." Doris in Colorado (Up2Nutrix@aol.com) "He is no fool who gives what he cannot keep to gain what he cannot lose." -- Jim Elliot, missionary and martyr