How old Is the Earth?

- 4.6 to 5 Billion Years Old

How long have bi-pedal hominids been walking the Earth?

- 3.5 million Years

How long have homo sapiens been walking the Earth?

- 100,000 Years Ago

How long have humans been recording (writing) history?

- 10,000 Years Ago- Marks the transition from prehistory to history

• Earth is over 5 billion years old. • Life first originated in the oceans 3.4 billion years ago. • The dinosaurs died out 65 million years in the past. • Human recorded history stretches back 10,000 years in time.

These numbers are too large to visualize, and difficult to compare. Here's an easy way to put time in perspective, and actually visualize different eras in the earth's history

• http://science.nationalgeographic.com/science/prehistoric-world/prehistoric-time-line/

So What does this mean?

Historians have stopped using BC/AD and have replaced with BCE (before common era) and CE (common era), why?

• Because of cultural considerations

http://chaos1.hypermart.net/fullsize/ancivfs.gif

Sources

• http://files.wts.edu/uploads/images/CTW%20Images/Demanding%20Reader/Sundial.jpg

• http://www.adhd-app.com/wp-content/uploads/2013/05/Time-Management-for-ADHD.jpeg