--- title: "Why sort living things?" subtitle: "Year 7 Biology · Classification · Lesson 1" --- # Why sort living things? **Name:** {{field-24}} **Date:** {{field-15}} **Class:** {{field-15}} > **Key question:** There are about 2 million named species of living things, and millions more not yet named. Without a system, how would anyone find their way around them? :::teacher-note **In one sentence:** Students explain why living things are classified (identifying, communicating, showing relationships), tell classification from a plain list, and give an everyday example (AC9S7U01, node 1). **Students should be able to say:** I can give two reasons why living things are classified. I can tell classification from a simple list. I can give an everyday example of classification. **Width:** the unmarked parts are the floor every student does (Engage, Explore, Explain, Evaluate). Typical and Wider sections add contexts, not difficulty. Students work in the online tutorial alongside this sheet. ::: ## Engage :::keep-together **A scientist finds a beetle she has never seen. Why does it help that beetles are already classified and named?** ☐ It doesn't help: classification is just a tidy list ☐ She can work out what it is, or show it is new, and tell other scientists exactly which beetle she means ☐ So the beetle can be put in a museum ☐ So she knows how many legs it has My prediction, and why: {{lines-3}} ::: :::teacher-note **What happens:** Classification lets her identify it (or show it is a new species), and its name lets scientists everywhere know exactly which beetle she means. Its group also tells her what it is related to. ::: ## Explore Try it on the board in the tutorial. Was your prediction right? What was different? {{lines-2}} ## Explain: what classification is for :::keep-together ### Reasons **Is it a reason scientists classify living things?** Groups: A reason to classify, Not a reason - To identify an organism they don't know: {{field-15}} - To use names every scientist understands: {{field-15}} - To see which organisms are related: {{field-15}} - To make the living world look neat: {{field-15}} - To decide which organisms are better: {{field-15}} ::: :::teacher-note **Answer:** To identify an organism they don't know → A reason to classify; To use names every scientist understands → A reason to classify; To see which organisms are related → A reason to classify; To make the living world look neat → Not a reason; To decide which organisms are better → Not a reason ::: :::keep-together ### Classification or a list **Which is classification, not just a list?** ☐ Writing animals in alphabetical order ☐ Grouping animals by shared features, such as backbone or no backbone, then smaller groups inside ☐ Numbering animals in the order you saw them ::: :::teacher-note **Answer:** Grouping animals by shared features, such as backbone or no backbone, then smaller groups inside Classification groups things by what they share, so the group tells you something about each member. ::: :::keep-together ### Everyday classification **A supermarket groups food by aisle: dairy, bakery, fruit. How is that like scientific classification?** ☐ Groups by shared features help people find things and talk about them ☐ It isn't: only scientists classify ☐ Both put things in alphabetical order ::: :::teacher-note **Answer:** Groups by shared features help people find things and talk about them Libraries, supermarkets and phone contacts all classify, for a purpose. Scientific classification's purposes are identifying, communicating and showing relationships. ::: :::typical ## Elaborate: two ways to group :::keep-together ### Which system **You could group these animals by where they live (land, water, air) or by body features (backbone, feathers, fur). Which is more useful for showing how they are related?** ☐ Body features: a platypus and a kangaroo share fur and milk, though one swims ☐ Both are equally useful for every purpose ☐ Where they live: animals in the same place are related ::: :::teacher-note **Answer:** Body features: a platypus and a kangaroo share fur and milk, though one swims Grouping by habitat suits some jobs (planning a reserve); grouping by shared features suits others (showing relationships). The purpose decides the system. ::: ::: :::wider ## Elaborate: other ways of knowing :::keep-together ### Different purposes **Many Aboriginal and Torres Strait Islander peoples group plants and animals in ways tied to Country: by uses, seasons, relationships between species and cultural knowledge. Scientific classification groups by shared features and ancestry. What does comparing them show?** ☐ Each system is built for its purposes, and each holds knowledge the other may not ☐ Only one of them can be correct ☐ Classification systems never change ::: :::teacher-note **Answer:** Each system is built for its purposes, and each holds knowledge the other may not Every classification reflects the purposes and knowledge of the people who built it. Ecologists increasingly work with First Peoples' knowledge of species and seasons. ::: ::: ## Evaluate: look back Write one sentence: "At first I thought… Now I think… because…" **Revision summary** - Scientists classify living things to **identify** them, to **communicate** clearly (one name everyone understands) and to show how they are **related**. - Classification groups by shared features; a list (alphabetical, by date) does not. - Every classification is built for a purpose; different purposes can suit different systems. ## Exit ticket :::keep-together **A new beetle is found in a Queensland rainforest. Give two ways classifying it helps scientists.** {{lines-3}} ::: :::teacher-note **Answer:** Any two of: others can identify it from its features; one scientific name lets scientists everywhere talk about the same beetle; its group shows which beetles it is related to. :::