A Timescale is a scale used to represent periods of time. Option: Have students make a timeline of their lives in their ... Explain that scientists also like to sort events in the order they have ...

Many different representations of the timeline have been created, and many approaches developed by informed, trusted sources. We will provide a list of web sites with relevant information. The ...

Prehistoric time line, geologic time scale, photos, facts, maps, and more from National Geographic. Humans have walked the Earth for 190,000 years, a mere blip in Earth's 4.5-billion-year history.

The geological time scale, established by scientists in the mid-19th century and agreed upon internationally, breaks down the eternity of our planet's history into more manageable units than years.