Small things can sometimes make big differences. Very small changes in temperature, we are now learning, can trigger big and consequential changes. As a child, I can remember my mother taking my temperature when I did not feel well. Whenever my temperature was around 100, just slightly more than 1 degree above normal, she acted fast, usually calling the doctor and sending me to bed, while frequently putting her hand on my forehead to check how hot I was. One degree above normal made me sweat and made her sweat more, not letting me go to school. I can remember a few times when my temperature rose to 103 or even 104. My mother saw this little spike as a big deal. She put me to bed and called the doctor immediately.