What Darwin Never Saw
Lesson Introduction
In this lesson, students take on the role of birds who migrate back to their nesting sites each summer. The birds in this simulation game, like the finches in the video, What Darwin Never Saw, will find that different amounts, or even different kinds, of food are available every year.
Following the game, students engage in a class discussion to help them identify some of the important environmental impact (definition) factors that produce ever-changing food supplies. The students see that members of a species (definition) often do not survive unless they are capable of adaptation (definition). Most important, students understand that all animal and plant populations do not remain constant. Only the most "fit" individuals of a species survive and have baby birds of their own, so its population's numbers change with each passing generation.
Grade Level
2 through 6
Objectives
The students will:
1. participate in a role playing activity.
2. name two factors affecting environmental conditions for wildlife populations.
Time Allotment
one 40-minute session
Materials
large area where students can migrate, either outdoors or indoors
flip chart or chalkboard
markers or chalk
video/video player
Books to Read
Dawn to Dusk in the Galapagos, by Rita Golden Gelman, Boston, MA: Little Brown, 1991.
Out of the Water, by John Bonnett Wexo, Mankato, MN: Creative Education, 1991.
Advanced Preparation and Teacher Notes
This activity is adapted from "Oh Deer!" which originally appeared in the Project Wild curriculum, developed by the Western Regional Environmental Education Council.
Procedure
Tap Prior Knowledge
1. Ask the students to think about changes in their own neighborhoods. What is different now from three years ago, for example? Does anyone in the class know of someone who moved from the neighborhood because of the changes, perhaps to get a different job or a different house to live in? Does anyone know of someone who moved to the neighborhood for similar reasons?
Share with Neighbor/Revise Ideas
2. Encourage students to talk to each other about what caused changes in the finch population when Peter and Rosemary Grant were carrying out their study on Daphne Major, one of the Galapagos Islands. Accept all responses. Show the section of the What Darwin Never Saw video (from 37 20 to 41 03) which shows the bigger-beaked finches getting the seed. Share one of the biographies from our Career Connections with the students.
Engage Students in a Hands-on Activity
3. Have students count off by threes. All of the ones will be finches. Gather them together on one side of the open playing area. All twos will be large seeds. All threes will be small seeds. Gather them at the other side, about 30 meters from the finches.
4. Introduce symbols to the students. The large seeds should hold their arms out to the sides to show that they are wide. The small seeds should bring their arms in, perhaps in a self-hugging motion, to show that they are small. The finches can either be big-beaked or small-beaked. Big-beaked will hold their arms out in front of them, placing them together like a large bird beak. Small-beaked will do a similar symbol, but just with their hands, held at the mouth.
5. Practice the four symbols with all of the students. Remind them that they may be any one of these during the game. It is important to know them all
6. Tell the finches to turn their backs and choose one type of finch to be (small or big-beaked finch), then make the appropriate symbol. Instruct the seeds, larger and small, to turn their backs and make their symbols.
7. Begin the first year migration by giving a signal to the finches to fly over to the nesting habitat. They fly while they maintain their chosen symbol.
8. When the finches arrive at the nesting site, they look for the seed that suits them. Small-beaked finches eat only small seeds. Large-beaked finches eat only large seeds. The student finches take the seed back with them and that seed becomes a finch - with the same kind of beak as the finch who ate it! Any student that does not find the right seed becomes a seed, either large or small. The choice is theirs. That completes one year of play.
9. Keep the track of finch population or designate a student to have that job. Record the number of finches on the flip chart or chalkboard at the beginning of the game and at the end of each round. The finch population should fluctuate each year. This happens naturally, with population peaking, declining, and rebuilding. During the course of the game you can manipulate the kinds of seeds available by telling students what particular seeds sizes to be.
Introduce the Scientific Principle/Concept
10. Patterns of weather, or climate, can change the environment to make it difficult for some plants and animals to survive. In the case of the finches on Galapagos Islands, dry weather made it difficult for finding smaller seeds. During times of drought, small seeds like pistachio nuts were quickly picked out and eaten by hungry birds. Only the larger seeds, from the Palo Santo, the cactus, and the Tribulus for example, were available in dry weather. Those birds with small beaks had a tough time. While humans and larger mammals can find substitutions when our primary diet is not available, smaller animal like the finches cannot. When their food supply is not available, they do not survive.
11. Other things that can change the environment are the introduction of an animal or plant which is not from the area originally. This non-native, or exotic, species has no natural predators and can easily take over the environment. A disease which kills off the plants or animals which make up a diet for another species can also be a major change. Finally, the development done by humans can drastically alter the environment, forcing some species to adapt or not survive. Because the environment is always changing, the overall populations of animals and plants change from year to year, just like they did in the simulation game.
Lesson Assessment
12. Have students each name two factors affecting environmental conditions for wildlife populations. They can do this orally or in writing.
Connect to Other Everyday Examples
13. Give students a chance to surf the World Wide Web to find out more about the finches on the Galapagos Islands:
