Some dolphin species face the threat of extinction, often directly as a result of human behavior. The Yangtze River Dolphin is an example of a dolphin species which may have recently become extinct.

Gases that build up in your large intestine cause flatulence. It usually takes about 30 to 45 minutes for these gases to pass through your system.

The Sears Tower consists of nine framed tubes, which connects nine skyscrapers as one building.

AMAZING FACTS