How Does the Body Make Vitamin D from Sunlight?
A Curious Reader asks: How exactly does exposure to sunlight cause the the human body to synthesize Vitamin D3?
Why Deep-Sea Creatures Get Weirdly Giant
A giant squid sighting has us wondering all over again: how on earth do deep-sea creatures get so large?
The Meaning of Methane on Mars
Curiosity rover's recent report of methane on Mars isn't the first time the gas has been indicated. Does it necessarily mean that Mars harbors life?
How Does a Scorpion Decide When to Sting?
There are actually two decisions to make: whether to sting at all and whether to use prevenom or full venom.
Mount Everest’s Death Zone
The zone above 8,000 meters is known among mountaineers as the “Death Zone.” Why do most deaths in the high mountains occur at these extreme heights?
The High Environmental Costs of Cruise Ships
Cruise ships pose many environmental concerns, from waste disposal to toxic paint to the creation of noise that can harm marine life.
How Snakes Swallow
A snake’s ability to swallow enormous prey has long been a source of fascination, but the common explanation that they dislocate their jaws is a myth.
The Sky’s Creepiest Parasites
Are you a bird? Is your chick acting weird? You might be victim of a brood parasite.
Why Tornadoes Are So Difficult to Predict
Scientists and weather forecasters have been trying to understand tornadoes for over 100 years, but the average advanced warning is still only 14 minutes.
