ANSWER: In general, a low heart rate is too low when it is causing symptoms such as fatigue, lightheadedness or fainting. Heart rates in the 40s are not unusual for trained athletes, especially when ...

A team of entomologists will be conducting the nation's first-ever statewide firefly inventory in Pennsylvania to learn about ...

Head south to see this flame-red, desert-dwelling bird. Learn where to find a vermilion flycatcher, and what their song sounds like.