DNA testing shows supposed yeti samples are actually from bears and a dog.
And they can serve as vectors of disease.
In 1992, scientists warned that humans had to change or the Earth would become unlivable. What's changed 25 years later?
Your tiny roommates like particular rooms in the house.
On a warmer planet, a volcanic eruption might disrupt global temperatures and precipitation for years after it happened.
Many of today's animals still use the same camouflage technique that sinosauropteryx used about 130 million years ago.
The Netherlands opened a 3-D printed concrete bridge for cyclists that uses less concrete - and cement - than traditional methods.
The Trump administration rolled the policy back in August, saying national park visitors should decide for themselves how to stay hydrated.
Poisonous and venomous animals have several tricks so their own defense mechanisms don't hurt them.
Illegal sand extraction has wide-reaching social, political and environmental effects.
Environmental groups want Interior Secretary Ryan Zinke to put Yellowstone grizzly bears back on the endangered species list.
The so-called ban was an effort to reduce plastic waste. The Trump administration says visitors should decide how to stay hydrated.