A timeline of natural history is like a picture of the most important events in the history of life on Earth. It's like looking at a map of the past and seeing how things have changed and developed over time. It starts with the earliest life forms emerging about 3.8 billion years ago and goes up to the present day. The timeline includes major events like when the first plants and animals evolved, continents formed and broke apart, and when the first humans appeared. It also shows when different species went extinct and when new ones evolved.