Ideas for Use in the Classroom

Introduce students to the map by having them identify the countries on either side of the line. Use context clues to decide on which side of the line the pictured animals belong. Then have students research and compile a list of mammals native to Asia's Sumatra, Java, and Borneo versus New Guinea and Australia. Ask: How do these lists differ? Have students research the difference between placental mammals, marsupials, and monotremes, and then categorize the mammals on each list accordingly. Prompt students to identify any patterns between the two lists. Students should observe that marsupials and monotremes exist on only one side of the Wallace Line, while most placental mammals are found on the other. Next, have students work in pairs to hypothesize reasons for the distributions they have identified.

After sharing their hypotheses, have students evaluate the map to determine what the different shades of blue represent within the ocean. Ask: How might ocean depth relate to the distribution of mammals? To emphasize this point, have students identify the islands on which rhinoceroses and tigers live, or have lived, and discuss what their distributions imply. Students may deduce that some islands were once connected due to changing sea level, while areas separated by deeper water were not. Contrast these animals with bats, which are found on either side of the Wallace Line, to demonstrate that ocean depth and land connectivity is a barrier to some animals, but not others.

As an extension, students can use the map to predict how flora and fauna on the islands surrounding the Wallace Line might compare to each other, Asia, and Australia based on geography and distance to the mainland.