Why Classify?

What is classification? Organizing things based on their characteristics and placing them in groups. Taxonomy – giving objects a name Just definitions

What do we classify? Everything can be classified! Living Organisms Animals Plants Bacteria Nonliving Things Rocks Gems Chemicals We are going to learn how and why we classify living organisms! Students brainstorm examples of things these people might classify

Aristotle Classified organisms by how they moved. If they moved – Animal If they didn’t move – Plant If they were an animal, what was their mode of transportation? Walking Swimming Flying This was a good start, but now we know a lot more that make his classification system inaccurate. Also mention that there have been other changes, like mushrooms starting out as plants because they looked and acted like plants, but as scientists learned more about mushrooms, there were many differences like its cell wall and how it gets its food. Even now, there are changes as scientists learn more about viruses, prions, and other things that don’t exactly fit into the kingdoms of life.

So what’s the problem? Things that move alike may NOT be related Things that don’t move alike may BE related Some things don’t fit in any category Some things can fit in several categories Here are some examples. Have the students come up with other examples. Example 1 – lizard and dog Example 2 – penguin and eagle Example 3 – Viruses Example 4 – Seals can walk on land and swim in water

Then what do we do? Agree on what to look at Agree on what to call it Change things when you find out more Classification system – Thanks Linnaeus! Classification key ( or dichotomous key) Binomial nomenclature (two names) Scientists agree to this even if they speak different languages

Let’s Get Started! We are going to start classifying some Martians!