For centuries, dyed fabrics ranked among the most expensive objects of the ancient Mediterranean world, fetching up to 20 times their weight in gold. Huge fortu

A variety of rare blue species--from the blue lobster to the blue black bear--are rare and unique for a reason. Travel across Earth to discover eight species th

"In 1979 the black robin of the Chatham Islands was on the brink of extinction, with only five birds left. When the Wildlife Service intervened to rescue them i

A lovely and tranquil celebration of nature The sun has set, the day has ended, but the night hasn't quite arrived yet. This magical twilight is known as the bl

What is it about the color blue? Blue is our favorite color globally—the darling of artists since the time of the pharaohs. So it’s startling to turn to the