Your finished timeline could look like the one to the right about American alligators in Florida. Each entry on the timeline includes a date, title, and an image. 

In this timeline, each point corresponds to an event or observation related to the alligator population. The entries are presented in chronological order, which means they are ordered by date. Notice that in this example, the dates are shown vertically, with the oldest date on the bottom and the most recent at the top. 

Biodiversity timelines tell a story of patterns and trends in nature, but they are really just the beginning! Each point launches a deeper investigation. In the following pages, you will explore a species timeline that presents significant events in the history of the bald eagle along with observations that serve as evidence of the changes in the population over time.