Skip to content
Your progress

Checking your sign-in…

Who's learning?

Each profile keeps its own read lessons, badges, streak, and practice scores on this device.

Lesson 1 of 10

Too many to list

Show on a big screen

6 min

Text size

Six animals at a zoo. How would you sort them?

Loading lab…

The rule

Sort the animals by one feature, such as what they eat. A feature is something you can check about a living thing.

Classification means sorting living things into groups by shared features. Change the feature, and the groups change.

The huge variety of living things is called biodiversity. Classification groups living things so we can study the variety more easily.

Many separate living things, each on its own.
Step 1 of 4
  1. Many separate living things, each on its own.
  2. A shared feature draws a box around some of them.
  3. A second feature splits one box again.
  4. Groups replace one long list.

One animal, many groups

The same six animals, grouped three ways
FeatureOne groupThe other groups
What it eatsEagle, tiger, shark, dolphin (flesh)Parrot, cow (plants)
How it movesEagle, parrot (flies)Tiger, cow (walks); shark, dolphin (swims)
Feeds its young milkTiger, cow, dolphinEagle, parrot, shark

Groups help you find a living thing fast. Some groups show which kinds are close relatives. Classification also gives scientists one shared name for each kind. It also helps protect living things in danger.

Try the lab to finish this lesson.