Implement this lesson:
After going through NOAA Ocean & Coastal Acidification Unit
Learning objective:
To understand the harm of ocean acidification on fish species such as a clownfish by conducting a hands-on kinesthetic activity.
Next Generation Science Standards (NGSS)
MS-ESS3-4
Construct an argument supported by evidence for how increases in human population and per-capita consumption of natural resources impact Earth’s systems.
Science and Engineering Practices
Engaging in Argument from Evidence Engaging in an argument from evidence in 6-8 builds on K-5 experiences and progresses to constructing a convincing argument that supports or refutes claims for either explanations or solutions about the natural and designed world(s). Construct an oral and written argument supported by empirical evidence and scientific reasoning to support or refute an explanation or a model for phenomenon or a solution to a problem.
Disciplinary Core Ideas
ESS3.C: Human Impacts on Earth Systems 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.
Crosscutting Concepts
Cause and Effect Cause and effect relationships may be used to predict phenomena in natural or designed systems.
Texas Essential Knowledge and Skills (TEKS)
K.6A use the senses to explore different forms of energy such as light, thermal, and sound
K.9B examine evidence that living organisms have basic needs such as food, water, and shelter for animals and air, water, nutrients, sunlight, and space for plants
K10B identify basic parts of plants and animals
1.6(A) identify and discuss how different forms of energy such as light, thermal, and sound are important to everyday life
1.10(A) investigate how the external characteristics of an animal are related to where it lives, how it moves, and what it eats
2.9(A) identify the basic needs of plants and animals
2.9(B) identify factors in the environment, including temperature and precipitation, that affect growth and behavior such as migration, hibernation, and dormancy of living things
2.9(C) compare the ways living organisms depend on each other and on their environments such as through food chains
Overview
Animals rely on their different senses to survive in the wild. Clownfish use an exceptional sense of smell as a way to help determine which direction to swim, called “olfactory homing”. When given a choice between two water currents, one with the scent of an anemone and the other with the scent of the open ocean, clownfish will choose the anemone scent nearly every time. They can also tell the difference between the scent of a predator and the scent of a friendly non-predator…like Dory. When given a choice they choose the nonpredator nearly every time. Ocean acidification has shown that the olfactory homing ability of clownfish is severely disrupted by ocean acidification (through interference with neuron function). That means clownfish have a hard time smelling the difference between the ocean, friendly non-predator fish, and predators.
Ocean acidification occurs when excess carbon dioxide gas, produced when humans burn fossil fuels such as coal and gas. This rampant carbon dioxide mixes with seawater, forms a weak acid and lowers the ocean pH. The acidity of the ocean has increased by 30% in just 200 years. This drop in seawater pH can impact the neuron function of some types of fish, including clownfish, which means that clownfish such as “Nemo” in the popular movie “Finding Nemo” may have a very hard time finding their way home or avoiding predators in the future.
Materials:
- At least five items with strong smells: vinegar, milk, dried rosemary, chocolate, cinamon, etc
- Small identical containers to hold the strong smells such as dixie cups
- Clothespins (optional)
- Blindfold (optional)
Advanced Prep:
- Teacher places the different smelling items into the small cups and labels what they are
- Choose one smell that will be the ‘anemone’ smell.
Procedure:
- Place students in groups or pairs. One student is the clownfish and the other student(s) are the helpers.
- The clownfish student is allowed to smell all the different smells. Make sure they closely smell the ‘anemone smell.’
- The clownfish student is blindfolded or asked to close their eyes. The helper student(s) helps the clownfish student smell each cup. The clownfish student has to identify which smell is his anemone. Record the information on the chart
- Repeat the experiment again except place a clothespin or other scent blocking device on the clownfish student. Repeat the experiment with the clownfish student trying to identify their anemone smell. This simulates how ocean acidification harms clown fish’s ability to smell.
| Before Ocean Acidification | After Ocean Acidification | |
| Number of students who correctly identified their anemone | ||
| Number of students who incorrectly identified their anemone |
Questions to Ask:
Pre-experiment
- What are some of your favorite smells?
- What are some of your least favorite smells?
- Have you ever noticed how certain places or people have certain smells?
- Do you think you could identify a person/place based on smell?
Post-experiment
- How hard was it to find your anemone smell before we close pinned your nose?
- How hard was it to find your anemone smell after we close pinned your nose?
- What do you think would happen to clownfish if they can’t find the smell of their anemone?
- Do you think other fish use their smell too? What do you think would happen to them?
Extensions:
-Watch video: https://www.youtube.com/watch?v=qAkhuETYn5U
-Repeat game with each smell having a different meaning (open ocean, predators, non-predatory fish, other clownfish, etc).
Evaluation:
-Have students draw a picture and write a sentence describing what would happen if they were a clownfish and couldn’t smell.
