I have a friend who says there's not much oxygen on earth. Ever since I heard that I can't catch my breath! What's the truth?
If you needed to know what the weather was like in Singapore tens of millions of years ago, you'd have to consult a different source.
Mountain climbers face many dangers as they brave the cold winds of the peaks they climb. But the most serious thing they face is all in their heads--literally.
There's one da Vinci of the body, a true Renaissance organ, which can perform functions of the lungs, liver, stomach and kidneys.
We humans are dependent on chemicals like water, air, sugars, starches, fats, proteins, as well as on small amounts of vitamins and minerals.
Adult painted turtles head underwater, where they'll spend the winter on the bottom of a lake, pond, or river but they use some tricks to survive the cold...
Global warming is a topic of political debate and scientific study these days. Is it happening? Scientists say the evidence is pointing in that direction.
If you could see an alien planet from Earth, you wouldn't necessarily need to look for cities. You could just check for oxygen in the atmosphere.
If you've ever received a special shipment of meat or seafood at home, it probably arrived surrounded by blocks of dry ice. What is dry ice?
Scientists have reconstructed a one hundred thousand-year history of carbon dioxide.