7.4.4.1 Human Activity
Describe examples where selective breeding has resulted in new varieties of cultivated plants and particular traits in domesticated animals.
Describe ways that human activities can change the populations and communities in an ecosystem.
Overview
Human activity can impact individual organisms and entire ecosystems.
Human beings, as part of earth's ecosystem, can effect change. Selective breeding is an example of human's altering plant and animals organisms to benefit human survival. Human activities, such as agriculture and other land development, have altered ecosystems and the plant and animal populations within them.
MN Standard Benchmarks:
● Describe examples where selective breeding has resulted in new varieties of cultivated plants and particular traits in domesticated animals. | ● 7.4.4.1.1 |
● Describe ways that human activities can change the populations and communities in an ecosystem | ● 7.4.4.1.2 |
THE ESSENTIALS:
©Gary Larson
Life Science
Content Standard C
As a result of their activities in grade 7, all students should develop understanding of
1. Structure and function in living systems
2. Reproduction and heredity
3. Regulation and behavior
4. Populations and ecosystems
5. Diversity and adaptations of organisms
Link to strand map Human Organism: Disease
8. The Designed World A: Agriculture
People control some characteristics of plants and animals they raise by selective breeding and by preserving varieties of seeds (old and new) to use if growing conditions change. 8A/M2*
Framework for K-12 Science Education
Genetic variations among individuals in a population give some individuals an advantage in surviving and reproducing in their environment. This is known as natural selection. It leads to the predominance of certain traits in a population and the suppression of others. In artificial selection, humans have the capacity to influence certain characteristics of organisms by selective breeding. One can choose desired parental traits determined by genes, which are then passed on to offspring. 8LS4.B
Ecosystems are dynamic in nature; their characteristics can vary over time. Disruptions to any physical or biological component of an ecosystem can lead to shifts in all of its populations. Biodiversity describes the variety of species found in Earth’s terrestrial and oceanic ecosystems. The completeness or integrity of an ecosystem’s biodiversity is often used as a measure of its health. 8LS2.C
Human activities have significantly altered the biosphere, sometimes damaging or destroying natural habitats and causing the extinction of many other species. But changes to Earth’s environments can have different impacts (negative and positive) for different living things. Typically, as human populations and per-capita consumption of natural resources increase, so do the negative impacts on Earth unless the activities and technologies involved are engineered otherwise. 8ESS3.C
Common Core Standards
Plotting and making graphs as well as using GPS will cross over with math classes.
Misconceptions
- 7.4.4.1.1 Middle school and high school students may have difficulties with the various uses of the term "adaptation" (Clough, E.E., Wood-Robinson, C. (1985). How secondary students interpret instances of biological adaptation. Journal of Biological Education. 19, 125-130; Lucas, A. (1971). The teaching of adaptation. Journal of Biological Education. 5, 86-90). In everyday usage, individuals adapt deliberately. But in the theory of natural selection populations change or adapt over generations, inadvertently students of all ages often believe that adaptations result from some overall purpose or design, or they describe adaptation as a conscious process to fulfill some need or want. Middle school students also tend to confuse non-inherited adaptations acquired during an individual's lifetime with adaptive features that are inherited in a population. (Kargbo, D., Hobbs, E., Erickson, G. (1980). Children's beliefs about inherited characteristics. Journal of Biological Education. 14, 137-146)
- 7.4.4.1.2 If a population in a food web is disturbed, there will be little or no effect on populations below it in the food web (e.g. if a predator is removed, no effect on prey: Webb, P., & Boltt, G. (1990). Food chain to food web: A natural progression? Journal of Biological Education 24(3), 187-190; Leach, J., Driver, R., Scott, P., & Wood-Robinson, C. (1996). Children's ideas about ecology 3: Ideas found in children aged 5-16 about the interdependency of organisms. International Journal of Science Education, 18(2), 129-141).
Vignette
Jim reached into the net and pulled out the aquatic plant. He handed that to Lavonne who compared it to the cards she held in her hand. She then asked Ms. Thorson about the shape of the blade and colors she saw.
"Jim, it is curly leaf pond weed. We were right." Lavonne reported.
This could take place on just about any lake in Minnesota. Invasive aqautic weeds have become a common concern all across the state. This scenario finds a group of middle school students on a local lake as part of a field study. The field study was organized by the teacher, Ms. Thorson, but in coordination with the local lake association. The lake association was able to provide chaperones, boats, life jackets and transportation on the lake surface in search of the local brand of invasive species, curly leaf pond weed.
Ms. Thorson, members of the lake association and the life science class had a town meeting in the classroom prior to the field study.
"What are we looking for? How will know if we will see it? What color is it? How deep is the lake? What does it do to the lake? Do fish like it or not?" These questions and others were generated by students. It certainly gave the local association some guidance in the resources they would need to successfully complete the study?
Stephan asked, "How did this get into Lake Tim? How is this invasive?"
Craig spoke up, "I used to be able to fish off the dock at the landing, but you can't anymore because of this weed. It gets caught in your bobber and you do nothing but hook it. I don't fish there anymore."
Ms. Thorson chimed in, "Stephan, that is a great question. How do you think you could find the answer?"
"I bet I could contact the MN DNR, they would probably be able to answer the question. I could just Google it too." Stephan replied.
Ms. Thorson answered, "That would be a place to start."
The Lake Tim association president spoke up. "We have plastic cards with pictures and identification for plants you will find in the lake."
Josh spoke up, "I live on Mud Lake, just up the highway, and we don't have curly leaf pond weed. How would my lake be different from Lake Tim?"
"Another great question! If this is an invasive species, how could we compare these lakes?" the teacher asked.
The thoughts came out fast and furious. "How does the species impact the fishing? What are the regular plants in the lake and how are they affected? Is this good for the lake?"
"Yeah, maybe invasive species aren't bad."
Craig called out again, "I don't fish anymore because of all these gross weeds, I say it's a bad deal!"
Ms. Thorson gathered the group together. "You've got some great points here, we need to compare the lakes. Could someone explain why?"
A long pause in the room, but you could see the minds spinning.
Rachel raised her hand. "You always need some kind of comparison, so you can decide which variable causes a change."
"So, what is the variable that could cause the change," asked Ms. Thorson.
Again, a pause, not as long as the previous.
Josh tossed his hand up, "The curly leafed pond weed is the variable, whether it is in the lake or not. Lake Tim has it, Mud Lake doesn't."
"What type of variable would you call it?"
"I would call the plant the independent variable and what happens to the lake the dependent variable," answered Stephan.
"What do you mean? What happens to the lake?" Ms. Thorson probed.
"Well, we've talked about the bobbers getting caught and not seeing any of the local plants and mats of this weed making it hard to ski and stuff. I would say that is the dependent that we can look at." Marissa said.
Ms. Thorson pointed to map of the lakes on the SmartBoard. "How can we divide up the lakes to get a survey? With the people at your tables, look at the lake map in front of you and come up with a plan." After a few minutes, the students brought back their recommendations to the group.
It was decided the lakes would be broken up into eight parts. Eight was chosen since the students knew there would be that many boats on each lake. With some discussion, the map on the SmartBoard was drawn upon and the various lake association members were given assignments. Each sector would be bounded by floating markers. The boat for each sector carries student survey teams to locate and identify the aquatic vegetation. Lake Tim and Mud Lake are relatively small lakes, so it was easy to divide and conquer.
Ms. Thorson asked, "What if the lakes were much larger? How would we survey?"
Royce was quick to raise his hand. "When we go fishing on Mille Lacs, we use a GPS to get from one spot to another. In a big lake, you could divide it up using GPS machines. You wouldn't need buoys or nothing."
"Yeah, and you could divide the lake up into big areas and divide those up." Reid answered, even though his hand never left the desk.
So, off the class went to survey Lake Tim and Mud Lake. The lake association members picked up their respective 'crews', drove to their assigned area and survey began. The crews determined a number of things: presence or absence of visible vegetation, identification of vegetation, identification of invasive species and placing that information on the map corresponding to their lake position.
The survey took a better part of the morning, but the crews were able to get back on shore, return to school and head back to class. Once there, the crews shared data on the SmartBoard, transferring their map to the big screen. The lake map showed the spread of the curly leaf pondweed was confined to several bays of the lake. Mud Lake, as reported, was free of the weed.
"So, how do you contain the plant?" inquired one of the girls.
"That is a tough question," replied the association member. They didn't like chemical controls suggested by certain members of their group and physical removal would be tough to continue. So, they remained stalemated.
Ms. Thorson had pointed out a sign at the boat launch. Removal all weeds, it had said.
Royce concluded, "The best advice is to make sure this doesn't spread to other lakes and streams. Make sure people clean their boats and trailers before they leave this lake. That has to be the only answer. We don't want this to spread to all the good lakes around. It ruins fishing and boating and all the fun we have in the water."
Resources
Instructional suggestions/options:
Students working with this standard should be outdoors and getting in touch with nature.
Using resources such as Project Wild, Wet and online resources found at the Canadian Parks and Wildlife Service (CPAWS), students become informed and engaged about the world outside the classroom. Better yet, use the outside as your classroom.
Selected activities:
- 7.4.4.1.1 Plant Propagation In these lessons, students research and carry out reproduction in plants and come to understand that most plants reproduce sexually, but can be forced to reproduce asexually.
- 7.4.4.1.1 Dog Variety Dogs come in a mind-boggling range of sizes, from tiny ones that fit in your handbag to those that can practically be saddled up like a horse. Strangely, cats don't seem to show the same level of diversity. This Science Update explores how selective breeding - selecting individuals that have a desirable trait and breeding them - will eventually get the population average of a species moving in the direction you've chosen.
- 7.4.4.1.2 Yellowstone Wolves To use the Internet to explore relationships between habitats and species (specifically the gray wolf and those species with which it must coexist) as well as the effect of physical and human forces on living things and their environment.
- 7.4.4.1.2 Seeing Purple Purple loosestrife is an aggressive nonindigenous plant that rapidly disperses throughout wetland areas. It is an unwelcome intruder because it interferes with the growth of native species and fills in the spaces where the natives would normally grow. Purple loosestrife creates many problems through its competitive advantage that cause an imbalance in the wetland ecosystem.
- 7.4.4.1.2 Great Lakes Worm Watch Making an Earthworm Observatory In the creation of a worm observatory, students will observe and record what happens during an earthworm invasion. Also students will have some hypothesis/research questions they will answer throughout. During the observing process students will acknowledge how the soil layers change from non-worm worked soil (unaltered) to organic material. The students observations should include visible color changes in soil layers, height of soil layers and burrows made by the earthworms.
- 7.4.4.1.2 Great Lakes Worm Watch Build a Forest and Make it Work In this game, the students will create a simple forest ecosystem model. Since there are no native earthworms in Minnesota our model doesn't have any either. Once students play with this system and understand how nutrients flow in it, then we add earthworms. Students can see how the changes caused by earthworms (or any exotic species) can change the rules of the ecosystem game and therefore, the ecosystem itself.
Additional resources or links:
- 7.4.4.1.2 Great lakes Invasive Species Gather some information about these invasives and the problems created by these human made problems.
- 7.4.4.1.1 Animal Cloning: ...Old MacDonald's Farm Is Not What It Used To Be: An online article about selective breeding on the modern farm.
- 7.4.4.1.1 Lessons from Texas about Longhorns This science curriculum is designed to meet Texas state standards and give a comprehensive overview of Genetics and Natural Selection including: phenotypes, genotypes, Punnett squares, species adaptation to biomes and a comparison between natural selection and selective breeding.
- 7.4.4.1.2 Opinion Cartoon Create a political cartoon that expresses an opinion based on information gathered on a topic.
Vocabulary/Glossary
- Selective breeding crossing of animals or plants that have desirable characteristics to produce offspring with desirable characteristics
- hybridization crossing of two genetically different but related species of an organism
- inbreeding breeding that involves crossing plants or animals that have the same or very similar sets of genes.
- Biotechnology is a field of applied biology that involves the use of living organisms and bioprocesses in engineering, technology, medicine and other fields.
- domesticated animals is an animal that can live with Humans.
- varieties any of various groups of plants or animals ranking below a species.
- cultivated plants plants that are grown for their produce.
- populations is all the organisms that both belong to the same species and live in the same geographical area.
- communities All the organisms living in a particular area or place:
- ecosystems a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving.
- Internet connections for students to do research on ecosystems, invasive species, human impact on ecosystems, etc.
- With new technology I-Pads would work well for students to use web sites listed above.
- Cameras/flip videos/microscopes to conduct for student research on invasive species.
- Great Lakes Data Choose among Great Lakes lessons and activities, data sets and tools. Any of these multidisciplinary resources may be incorporated into your curriculum. All the materials on this website are free.
- Hardware cameras that connect to microscopes for seeing and photographing microorganisms.
- GPS units for doing original field work. Geocaching
Social studies may cross over when studying biomes.
Assessment
Students:
In 1893, a large area of a national forest was home to mountain lions, coyotes, and bobcats as well as about 3,000 deer.
The deer ate grass, and the mountain lions, coyotes, and bobcats ate deer.
Around 1900, hunters began killing large numbers of mountain lions, coyotes, and bobcats. By 1923, there were 100,000 deer in this population.
Using only the relationships between the plants and animals described above, which of the following statements could explain why the population of deer increased so much?
1. The number of deer increased because without predators, the deer lived longer and had more offspring that also lived longer.
2. The number of deer increased because populations are always increasing.
3. The number of deer increased because with fewer mountain lions, coyotes, and bobcats, the deer had more food to eat.
4. There is not enough information to tell why the deer population increased.
Which of the following can limit the growth of a population of organisms?
1. Both diseases and the availability of resources can limit the growth of a population of organisms.
2. Diseases can limit the growth of a population of organisms, but the availability of resources cannot.
3. The availability of resources can limit the growth of a population of organisms, but diseases cannot.
4. Neither diseases nor the availability of resources can limit the growth of a population of organisms.
Which of the following statements about competition between animals is TRUE?
1. Competition may involve two lions fighting over prey but not two cows eating grass in the same field.
2. Competition may involve two birds fighting over a nesting site but not one bird placing its eggs in the nest of another.
3. Competition may involve two birds fighting over a nesting site, two lions fighting over prey, or one bird placing its eggs in the nest of another but not two cows eating grass in the same field.
4. Competition may involve two birds fighting over a nesting site, two lions fighting over prey, one bird placing its eggs in the nest of another, or two cows eating grass in the same field.
Teachers:. Questions could be used as self-reflection or in professional development sessions.
- Are we as educators teaching students to be good stewards of our resources?
- Is selective breeding becoming a tool for profit?
- Is genetic engineering the wave of the future?
Administrators:
- Students outside using GPS. In Project GLOBE students may be engaged in ground truthing, where they are providing exact longitude and latitude for scientists who are studying ground cover changes in an area, or they may be providing coordinates, along with elevations as a community looks at flood potential.
- Students researching invasive species on the internet. Students may be creating websites that can be linked from the district/school pages, providing service to the school district's constituents.
- Administration would be asked to help coordinate the busing to and from the vignette site, plus provide coverage for classroom teachers leaving the building to help with the lake study.
Differentiation
Struggling and At-Risk:
Snow, D. (2003). Noteworthy perspectives: Classroom strategies for helping at-risk students (rev. ed.). Aurora, CO: Mid-continent Research for Education and Learning.
In 2002, McREL conducted a synthesis of recent research on instructional strategies to assist students who are low achieving or at risk of failure. From this synthesis of research, McREL identified six general classroom strategies that research indicates are particularly effective in helping struggling students achieve success.
Hands on labs like the one in the vignette helps special ed students comprehend concepts better than straight book work.
Herr, N. (2007). The sourcebook for teaching science. This page contains strategies to help teachers better attend to the needs of their ELL learners. These strategies are grouped according to the following learning tasks: listening, visualization, interpersonal communication, laboratory, demonstrations, reading and writing, instruction and vocabulary.
Hands-on science learning promotes language connections
Have students label invasive species in English and their native language.
Multicultural science education. Official NSTA Position Statement.
Freelang.net hosts a English to Ojibwe and Ojibwe to English dictionary that may be used to look up meanings to vocabulary words.
Science education should include the use of culturally relevant content. Atwater and Banks (Ferguson, Robert. "If Multicultural Science Education Standards' Existed, What Would They Look Like?." Journal of Science Teacher Education. 19.6 (2008): 547-564. Print.) have proposed several ways to integrate culturally relevant content into the curriculum. The value of using such approaches is that they can improve the conversation about beliefs in science and hone beliefs about science for all students.
Technologies for Special Needs Students: In their newsletter, "Tech Trek", from the National Science Teachers Association, there are suggestions for using technology including voice recognition software
Hands on labs like the one in the vignette helps special ed students comprehend concepts better than straight book work.
learning experiences should be as multi-sensory as possible and safe. Such experiences have an added benefit too. They are effective with all learners.
Instruction should include direct experience with the materials of science
The ability to get out in the field and collect data first hand will help these students connect the concepts.
Parents/Admin
- Students may be reminding parents to check their boats for invasive species when traveling to different lakes.
- Parents may hear about the Most wanted invasive species.