What are organisms?

Organisms are different kinds of living things. You’re already familiar with the names of many organisms like humans, bald eagles, plants, birds, snakes, mammals, and fungi.

The Tree of Life describes how all organisms are related. Organisms can all be thought of as positions on the tree. Some are really groupings, like Ladybeetles, and refer to entire branches. Others, like Seven Spotted Ladybeetle, refer to individual leaves on the Tree. This means that an observation can correctly be identified as one of several organisms. For example, a beetle might be identified as a Ladybeetle or a Seven Spotted Ladybeetle. Both could be correct with Ladybeetle as a coarser identification than Seven Spotted Ladybeetle.

We’ve bookmarked ten positions on the Tree of Life with icons and colors so you can find them easily. These are good places to start exploring finer branches and leaves.

Sometimes, its useful to think of the Tree of Life as a family tree. Just like your parents are the common ancestor of you and your brother, the taxonomic genus Typical Ladybeetles is the common ancestor of the Seven Spotted Ladybeetle and the California Ladybeetle. And like the common ancestors of you and your second cousin are your great grandparents, the common ancestor of Seven Spotted Ladybeetle and Spotted Cucumber beetle is the taxonomic order Beetles.

We use the terms parents and children to refer to the most immediate ancestors and descendants respectively. And we refer to positions in the direction of ancestors as coarser positions.