Why Are Plants Green?
The dominance of green chlorophyll on Earth may have come after a more purple period.
Why Is It?
Living Cells
You probably have heard that hair is made up of dead cells. But are living cells really "alive"?
Wisdom Teeth
Why do we get wisdom teeth if they often don’t even fit in our jaws?
24-Hour Colds
Why you sometimes feel a cold coming on, only to have the symptoms disappear the very next day.
Mountain High
Have you ever been to a high altitude and found yourself gasping for breath? One listener asked why …
Brilliance Stereotypes
Gender stereotypes about extreme intelligence take hold in the early school years.
Crowd-sourcing Better Tomatoes
Researchers turn to panels of taste testers to identify key flavor chemicals lost during the past …
Germy Fabrics
Objects like blankets and stuffed animals can theoretically spread illnesses, but it’s unlikely.