Science 8

Core Unit: Adaptation and Succession

Unit overview

What characteristics of organisms enable them to survive in a particular environment? How do organisms alter the abiotic components of their environment? How does this alteration affect the abilities of the plants to live there? Can individual organisms change if the conditions change? These are questions about adaptation and succession.

Adaptation is not about the changing of organisms to suit the environment. It's about organisms changing the environment enough to be able to survive, or finding an environment that doesn't need changing.

This unit continues the investigation begun in the Ecosystems unit in grade 6. The concepts introduced in grade 6 can be considered in more depth, and new concepts introduced during this unit. The grade 9 unit Saskatchewan - Environment extends this look at the environment to focus on how humans are the prime agents of succession in today's world. Succession is an organic process in which organisms alter their environment. Students are asked to evaluate how human organisms have participated in the process.

Science writing and reading activities, as discussed in this Guide, should be incorporated into each lesson. Writing demands that we clarify our thoughts and ideas. Reading exposes us to the thoughts and ideas of others. Including writing in science activities is an important component of the science program. The writing may be expository, narrative, or personal and reflective. Different modes suit different opportunities and purposes. Students should be encouraged to read newspaper and magazine articles, narrative nonfiction, and texts. Through reading and writing they refine their understanding of the concepts of science and develop their ability to communicate through the written word.

Science challenge, as described in this Guide, is meant to extend students' critical and creative thinking abilities in the context of the science concepts being studied. Activities involving science challenge should be incorporated into science lessons in each unit. The challenge is intended to give each student a chance to investigate an area of interest in more depth than would be possible for all students in a class to do. Science challenge is a key strategy for bringing the Adaptive Dimension to the classroom, and for encouraging independent learning.

Factors of scientific literacy that should be emphasized

• A2 historic
• A7 unique
• B1 change
• B2 interaction
• B4 organism
• B14 cycle
• B16 system
• B18 population
• B22 fundamental entities
• C6 questioning
• C9 inferring
• C11 controlling variables
• C13 formulating models
• C18 using time-space relationships
• D2 scientists and technologists are human
• D4 science, technology, and the environment
• E1 using magnifying instruments
• E2 using natural environments
• E7 manipulative ability
• F1 longing to know and understand
• F4 valuing natural environments
• F6 consideration of consequence
• G3 continuous learner
• G5 avocation

Concept development

• grade 2
  • factors influencing plant growth, and the habitats of plants and animals
• grade 3
  • soil characteristics
  • the pressures on animal populations
• grade 5
  • human impact on the environment
  • concern for quality of air, soil, and water
• grade 6
  • interrelatedness of biotic and abiotic components of the ecosystem
• grade 7
  • requirements for life
• grade 8
  • factors influencing plant growth
• grade 9
  • human impact on the ecosystem

Foundational and learning objectives for Science and the Common Essential Learnings

1. Recognize how abiotic components of an ecosystem support and influence life .
   1. Identify the nonliving conditions and components of the ecosphere that influence life.
   2. Discuss the interrelationships among the nonliving components.
   3. Analyze the role of matter cycles in an ecosystem, considering both abiotic and biotic components.
   4. Recognize energy sources and energy flows in the ecosystem.
   5. Appreciate how abiotic factors influence how populations which develop.
   6. Examine the behaviours and mechanisms by which organisms make use of, and coexist with, the abiotic components of the ecosystem.
   7. Explore the behaviours and mechanisms by which organisms make use of and coexist with other biotic components of the ecosystem.
2. Examine how living things alter their environment.
   1. Find examples of succession in the ecosystems of your area.
   2. Observe and describe the rate of environmental change.
   3. Assess how living organisms contribute to environmental change.
   4. Evaluate the effect of succession on ecosystems.
3. Develop a positive disposition to lifelong learning. (IL)
   1. Participate in learning activities, individually and as members of a cooperative group.
   2. Contribute to the development of objectives for learning activities.
   3. Identify, plan, and conduct activities.
   4. Develop a willingness to take risks as an independent learner.

Suggested activities:

Note: Many of the resources listed in Science: An Information Bulletin for the Middle Level - Key Resource Correlations describe activities or ideas for activities.

1. Create a model or a mural which illustrates the water cycle. Highlight all the places where the water cycle has an impact or an effect on human life.

   Factors: A2, B1, B14, B22, C13, C18, F1, F6

   Objectives: 1.1, 1.3, 1.5, 3.3

   Assessment Techniques: group evaluations, rating scales, presentations

   Instructional Methods: cooperative learning groups, reports

2. Identify the source(s) of water supply for the community in which your school is located. Investigate whether there have been or are any threats to the quantity or quality of that supply. Identify the biotic and the abiotic factors which interact with the community's source(s) of supply.

   Factors: B2, B16, C6, C9, D4, E2, F1, G3

   Objectives: 1.1, 1.2, 3.1

   Assessment Techniques: written report, extended open response test items

   Instructional Methods: research project, interviewing, reading for meaning

3. Create a model or a mural illustrating the carbon cycle. How do the carbon cycle and the water cycle interact with each other or influence each other?

   Factors: A2, B2, B14, C13, C18, F4, G3

   Objectives: 1.3, 3.1

   Assessment Techniques: homework, written assignments, observation checklists

   Instructional Methods: model building, research project, discussion

4. Follow the previous activity with a class discussion comparing and contrasting how humans cope with their environment. Are physical characteristics or behaviours more important in human adaptation?

5. List on the board all plants and animals which can be found in the vicinity of the schoolyard. Ask each group to pick one organism listed. For the organism they have selected, they should describe the behaviours and the physical characteristics which help the organism cope with its environment. Each group can share its findings and ideas with the whole class in the form of an oral presentation illustrated with one or more posters. Species identification is not critical Ä labelling them as A, B, C, etc. would suffice.

6. Brainstorm a list of all migratory animals. The Resource Reader (being redeveloped) from Saskatchewan Natural Resources is a good source of information on migratory animals if the brainstormed list comes up short. Assign one animal to each pair of students in the class. Select animals so that a range of animals is allotted. (This is to avoid reports on the mallard, the canvasback, the green-winged teal, the blue-winged teal, the pintail, the wood duck, the shoveller, and the ruddy duck as the only reports prepared.)

   Each group of two should prepare a report outlining the characteristics, habits, and migratory path or habit of their animal. Each pair should present their report orally, using a globe to show the migratory path or habit. Each student in the class should have a copy of a world map on which to mark the migratory paths as they are described.

7. During the course of the year, assign groups the responsibility for assembling and mounting a bulletin board display. An appropriate concept for this unit could be either a grassland community, an aspen parkland community, or a boreal forest community. Included with pictures and articles about the selected community should be student- created posters explaining the function of each important element of the community. These elements would include such things as the sun, air, moisture, soil, producers, various consumers, and decomposers.

8. Create a model or a mural illustrating the nitrogen cycle. Be able to explain the importance of the nitrogen cycle to organisms and the concept of 'fixing' nitrogen.

9. Identify five to ten living organisms which form significant populations in the area in which you live. Identify the major links to other living organisms and to the abiotic components of the area.

10. In late April or early May, cultivate a small plot of soil (perhaps 1 metre square) in your schoolyard. Use a spade and hoe to make sure that the soil is well-tilled to a depth of about 15 cm, and is completely free of plant growth.

    Observe the plot over a one or two month period. Keep a record of the plant growth (number of species, population of each species, whether members of the species are also found in the immediate neighbourhood of the plot). If possible compare the schoolyard plot to plant growth in other disturbed soils in the community, such as building construction sites, abandoned lots or gardens, clearcut forest sites, road construction areas, and so on.

    If possible, leave the plot undisturbed over the summer and ask the grade eight class of the next school year to observe the plot and then create their own new plot in the spring. Over the years, this could create a longitudinal study of schoolyard succession.

11. Investigate how lichens are involved in succession. Find some rocks with lichen on them. Examine the lichen's characteristics and growth pattern, and the rock surface under the lichen. Is there evidence that the lichens have had an effect on the rock?

12. Go on a hike to a nearby park, open field, aspen grove, or forest. Identify the plants and animals that inhabit the area. How are they adapted (suited) to live in that space, and occupy the niche they do?

13. Create a mural which shows how succession would proceed on a bare sand hill in the Great Sand Hills area of southern Saskatchewan. Other murals could be created to show succession on an abandoned field in the Milestone area, an abandoned field in the Hepburn area, and on a clearcut forest area near Hudson Bay.

14. If a four wheel drive vehicle or a trail bike is driven across a sand dune community, the whole community, not just that part of it in the tracks of the vehicle, may be destroyed. If the same vehicles are driven across a patch of fescue prairie or through a spruce forest, there may be only minimal damage to the plants squashed by the tires. Why is there such a difference?

15. Analyze two distinct environments in terms of the abiotic factors which give them their character. A hill with a north facing slope and a south facing slope is example of a place where distinct environments may be found close to each other. Others might be the margin of a slough compared to a grassy ditch, or the play area of the school compared to a lawn.