For most infants, introducing peanuts early can help prevent allergies later on — but a new study reveals most caregivers don't know that. Why? Plus — some summertime advice for keeping pets cool in the heat, and avoiding beaches contaminated with poop. (A lot of them are.) All Things Considered host Mary Louise Kelly joins Regina G. Barber and Aaron Scott to discuss those stories in our science news roundup.Have questions about science in the news? Email us at shortwave@npr.org.