Science Common Sense

331 - How do we define and classify living things?

To define and classify living things, we use a system called taxonomy or classification. We look at the characteristics of each living thing, like its shape, size, what it eats, and how it reproduces.

We group living things into categories, starting from the biggest group to the smallest. These groups are:

1. Kingdom: This is the biggest group. There are six kingdoms: Animalia (animals), Plantae (plants), Fungi (fungi), Protista (single-celled organisms), Chromista (algae), and Monera (bacteria).

2. Phylum (or Division): This group is smaller than the kingdom.

3. Class: This group is even smaller.

4. Order: This group is smaller than the class.

5. Family: This group is a bit smaller.

6. Genus: This group is very small.

7. Species: This is the smallest group. It's a specific type of living thing, like humans or dogs.

For example, if we were to classify a human, it would look like this:

• Kingdom: Animalia
• Phylum: Chordata
• Class: Mammalia
• Order: Primates
• Family: Hominidae
• Genus: Homo
• Species: Homo sapiens (that's us!)