Did you know

1. The human body can regenerate its entire skin every 28 days.
2. The world's oldest tree is a bristlecone pine in California, estimated to be over 5,000 years old.
3. Earthworms have five hearts.
4. The population of the Earth is about 8 billion people, but there are an estimated 100 trillion ants.
5. The Great Wall of China is not visible from space.