CLASSIFICATION OF ORGANISMS

Question:How do classification systems work for unknown organisms?

Background: Imagine it's the year 2525. A planet similar to Earth has recently been found in a newly identified solar system in another galaxy. We have sent a space probe with a molecular transport beam to this planet to beam back a variety of different living creatures. Scientists examine the structure of each of these creatures and realize that they need to create a classification scheme to help them compare the alien life forms to each other and discover how they might be related.The lead scientist sends you illustrations of the organisms and asks you to help develop this classification system.

  1. Why do we classify things?

Hypothesis: If you study the illustrations then you can come up with a possible classification scheme based on the information provided about each organism.

(You'll be asked to explain to how and why you organized the creatures.)

Materials:

scissors critter cards (2 sets)paper and pencil or pen

Procedures:

1. Cut out the critter cards below. You should have 24 cards. Notice one set of 4 cards is “boxed”. Keep these separate from the other 20 cards.

2. Study all the cards (except the boxed four), noting similarities and differences among the creatures. Create a Table #1 on your paper to help organize what you see. You might have columns to describe bristles, antennae, eyes, etc. You might want to number your cards to help keep track of which you're describing.(Table #1 is to help you create Table #2. Table #1 is similar to a rough draft!)

3. Now put the cards (except the four you've kept separate) into groups based on the similarities and/or differences you see. Each group should include creatures that have something in common. These common traits by group should be CLEARLY listed in Table #2. Table #2 is similar to your final draft!)

4. Choose one of the cards from the four you've kept separate. This is a picture of a creature was just beamed back by the space probe and sent to you by the lead scientist. You need to decide where it fits in the group system you've just created or do you need to make a new group for this creature?

Observations:

Table 1Table 2

Analysis

  1. Write a brief paragraph explaining how your classification scheme works.
  2. Is your way (in the table) the only way possible to organize the creatures?
  3. Were you able to classify the new creature using the table you made? How easy or hard was it? Explain.

Conclusions Your conclusion should be at least 5 sentences.

GOING FURTHER: With your second set of cards, create a dichotomous key with at least 4 defining statements used to separate the creatures.