Readers respond to antibiotics, carbon bonds and more

Your comments on the December 24, 2016, and January 7, 2017, issues of Science News

Power struggle

Ninety percent of people who believe that they are allergic to penicillin are not, Emily DeMarco reported in “Most penicillin allergies are off base” (SN: 12/24/16 & 1/7/17, p.