The modern system of classifying living things allows us to organize thousands of species into a handful of "family trees" in which members share certain characteristics. In this unit, students devise their own animal classification system to prompt them to think about which characteristics are essential. They use the Visual Ranking Tool early in the unit to help them find out what they already know (and need to know) about classification systems. Then, they learn about the classification system developed by Linnaeus and revisit the tool to assess how well they have grasped and can apply the concept of scientific classification.
- Essential Question
Does everything have its place?
- Unit Questions
How can we classify animals for study?
How are animals like us?
- Content Questions
What characteristics are important for classifying or grouping animals?
How did Linnaeus develop the classification system that bears his name?
This project idea makes use of the Visual Ranking Tool. Examine the Visual Ranking Web site and familiarize yourself with the tool.
In groups, give students a set of similar materials such as all different kinds of buttons. Instruct each group to organize their buttons on at least four different levels (such as color, number of holes, type of material, and type of button). Groups should decide what level is the most general to most specific. Have groups share their classification systems. Students begin a science journal and record their initial response to the Essential Question, Does everything have its place? Have students reflect on the advantages of classifying objects.
Next, pose the Unit Question, How can we classify animals for study? Working in pairs, students are given a list of animals and asked which one most resembles a human. They use Visual Ranking to put the animals into order, ranking them on their human-like qualities. Using the comment feature, students explain their justification in a few words.
Next, have each pair use the compare feature to analyze the rankings from the rest of the class and deduce what characteristics they used to rank the animals and what order each team used their characteristics. For example, if one team has rated the monkey as most human-like because it looks most like a human, then the characteristic being applied is "physical." Another team has rated the dog high on its list because dogs and humans often live together. The characteristic being applied is "habitat." Instruct the pairs to write an analysis comparing its characteristics with other teams’ characteristics indicating which team had the highest correlation; also have them include a rationale for the high correlation. Have each team revisit and amend its original ranking to include the characteristics that they did in fact use to classify that animal.
Working as a class, students agree on a set of characteristics that they will use to classify animals referencing the list they created previously in pairs. Next, have the students place these characteristics in order of importance. The resulting class list is posted. Have students amend and edit the list as the unit progresses and their understanding grows. Use a variety of hands-on activities to give students opportunities to use these characteristics to practice classifying different animals.
Through readings, films, and online resources, teach students about the system of classification developed first by Aristotle and then much later by Linnaeus and finally the modern classification system (based from Linnaeus) used today. Help students gain an understanding of why Aristotle’s system was replaced by Linnaeus and why Linnaeus’s system was modified. Provide students a list of animals from the phylum Chordata. Have students conduct in-depth research about their chosen animal from the list, including information about their characteristics and classifications.
Finally, have students return to Visual Ranking. Have students analyze the rankings and decide on which pair came closest to the official classification characteristics used today (or even those in the past). Next, have students edit their original rankings by classifying which animal is closest to a human, scientifically speaking; which is next closest; and so on. Have students justify their reasoning, citing knowledge learned during the unit. Be sure students cite and reference their information. Use the Visual Ranking’s comment feature to review students’ comments and assess student thinking.
Examine the Visual Ranking Activity
The Visual Ranking workspace below represents one team's ranking on this project. The view you see is functional. You can roll over the white icon to see the team's comments and click the compare button to see how different teams ranked the items.
Project Name: Most Like a Human (Click here to set up this project in your workspace)
Question: Which animals are classified closest to humans? Please rank the following animals from most like a human to least like a human.
Explore an interactive demo.
Revisit the Essential Question, Does everything have its place? Students write an essay to analyze their thoughts and ideas about this question, supporting their thinking with examples from their research. A rubric or scoring-guide should be used to assess students’ individual essays.
At a Glance
Grade Level: 5-8
Higher-Order Thinking Skills: Decision Making, Analysis
Key Learnings: Characteristics of Living Things; Understanding the Classification System Developed by Linnaeus
Time Needed: Five, 45 minute lessons