Printer Friendly
Title
Activity: Aquatic Invertebrate Behavior
NGSS Crosscutting Concepts

Materials

  • Table 3.9
  • Table 3.10
  • Table 3.11
  • Live invertebrates
  • Aquaria or other appropriate containers for live specimens
  • Aquarium water (freshwater or seawater, depending on the species)
  • Stopwatch
  • Long blunt probe (e.g., stirring rod or pencil with eraser)
  • Colored pencils
  • Pipet or eye-dropper
  • Desk lamp
  • Black construction paper or posterboard
  • Various potential food items (e.g., algae, fresh or frozen fish, etc.)
  • String or twine
  • Hand magnifying lens
  • Dissecting microscope (optional)
  • Towels

Procedure

A. Prepare the live specimen for behavioral observations.

  1. Gently place the live animal in an appropriately filled aquarium or other container.
    1. Do not intentionally agitate the animal or tap on the aquarium glass.
    2. Allow the animal to rest and settle into its new habitat before continuing on to Part B.

NOTE: Ask your instructor what type of water is appropriate for each species. Do not use regular tap water for freshwater invertebrates. Instead use only specially prepared aquarium water.

 

  1. Familiarize yourself with the anatomy of the specimen.
    1. Use colored pencils to draw a detailed sketch of the specimen.
    2. Label as many anatomical parts as possible. You may use the text or other resources as references if necessary.
    3. Label the anterior and posterior aspects of the organism.
    4. Label the ventral and dorsal aspects of the organism.
    5. Compare your labeled sketch to the sketches made by your classmates to confirm terminology and proper identification of anatomical parts.
       
  2. Familiarize yourself with the technical terms commonly used to describe behavior (Table 3.9).
     
  3. If possible, determine the species and sex of your study organism. Write this information in Table 3.10 and Table 3.11.

B. Observe baseline behavior in the absence of any experimental stimuli.

  1. Estimate the size of your study organism. Write this information in Table 3.10 and Table 3.11.
     
  2. General behavioral observations and characterizations
    1. With a notepad, pencil, and stopwatch, observe the live animal for two minutes. Focus on the animal’s movement.
    2. Make note of which anatomical parts are moving and record this information in Table 3.10.
    3. Write a list of your behavioral observations in Table 3.10.
    4. Characterize or name the behavior and describe the movements in detail. For example, the teacher might observe “tail-wagging” in a dog and describe it as the repeated side-to-side, or lateral, movement of the dog’s tail.
    5. Record the frequency of the behavior (how often it occurs) and its duration (how long the behavior continues).
    6. Draw labeled diagrams depicting the organism’s movements and behaviors as necessary.
       
  3. Discuss your list of observed behaviors with your classmates. Agree upon a single list of behaviors for the organism with detailed definitions.

C. Observe behavior in response to various experimental stimuli.

  1. Light stimulus
    1. In Table 3.11, write a brief prediction of the animal’s response behavior to light stimulus.
    2. Gently move the animal to the center of the aquarium.
    3. Shine a bright lamp on one side of the aquarium.
    4. Cover the other half of the aquarium with black construction paper or posterboard. Allow sixty seconds for the animal to react to the light stimulus.
    5. Write a detailed description of your behavioral observations in Table 3.11. Record the frequency of the behavior (how often it occurs) and its duration (how long the behavior continues).
    6. Draw labeled diagrams of the response behavior.
    7. Turn off the lamp and allow the animal time to rest before continuing on to the next step.
       
  2. Water jet touch stimulus
    1. In Table 3.11, write a brief prediction of the animal’s response behavior to water jet touch stimulus.
    2. Gently move the animal to the center of the aquarium.
    3. Fill a pipet full with aquarium water.
    4. Slowly lower the pipet tip towards the animal’s sensory organs.
    5. Slowly squeeze the pipet to shoot a continuous jet of aquarium water towards the animal. Refill and continue the water jet touch stimulus until you see a response, for up to two minutes.
    6. Write a detailed description of your behavioral observations in Table 3.11. Record the frequency of the behavior (how often it occurs) and its duration (how long the behavior continues).
    7. Draw labeled diagrams of the response behavior.
    8. Allow the animal time to rest before continuing on to the next step.
       
  3. Blunt probe touch stimulus
    1. In Table 3.11, write a brief prediction of the animal’s response behavior to blunt probe touch stimulus.
    2. Gently move the animal to the center of the aquarium.
    3. Slowly lower a long blunt probe (such as a stirring rod or the eraser-end of a pencil) into the aquarium towards the animal.
    4. Gently touch the animal with the probe.
    5. Write a detailed description of your behavioral observations in Table 3.11. Record the frequency of the behavior (how often it occurs) and its duration (how long the behavior continues).
    6. Draw labeled diagrams of the response behavior.
    7. Allow the animal time to rest before continuing on to the next step.
       
  4. Inversion or gravity stimulus
    1. In Table 3.11, write a brief prediction of the animal’s response behavior to inversion stimulus.
    2. Gently move the animal to the center of the aquarium.
    3. Gently lift the organism and flip it upside down (ventral or belly side up). For echinoderms, try to turn the organism so the mouth-end faces upward.
    4. Write a detailed description of your behavioral observations in Table 3.11. Record the frequency of the behavior (how often it occurs) and its duration (how long the behavior continues).
    5. Draw labeled diagrams of the response behavior.
    6. Allow the animal time to rest before continuing on to the next step.
       
  5. Food stimulus
    1. In Table 3.11, write a brief prediction of the animal’s response behavior to food stimulus.
    2. Gently move the animal to the center of the aquarium.
    3. Tie a piece of string or twine around a variety of possible food items that the organism might encounter in its natural habitat.
    4. Slowly lower one food item into the aquarium. Allow the food item to rest on the bottom of the aquarium near the animal.
    5. After observing the animal’s response behavior to the food stimulus, carefully remove the food item from the aquarium.
    6. Repeat steps 5c and 5d with each individual food item.
    7. Write a detailed description of your behavioral observations in Table 3.11. Record the frequency of the behavior (how often it occurs) and its duration (how long the behavior continues).
    8. Draw labeled diagrams of the response behavior.
    9. Allow the animal time to rest before continuing on to the next step.
       
  6. Optional: Conspecific interactions
    1. In Table 3.11, write a brief prediction of the animal’s response behavior to conspecific individuals. The term conspecific describes organisms of the same species.
    2. Gently move the animal to the center of the aquarium.
    3. Obtain another individual organism of the same species.
    4. If possible, record the sex and size of this second individual animal.
    5. You may need to add a safe marking to the second animal to distinguish it from the first animal. Nail polish or masking tape can be used on mollusc shells or arthropod exoskeletons.
    6. Gently place this second animal into the same aquarium as the first animal.
    7. Write a detailed description of your behavioral observations in Table 3.11.
    8. Remove the second animal, and allow the first animal time to rest before continuing on to the next step.
       
  7. Optional: Interspecific interactions
    1. In Table 3.11, write a brief prediction of the animal’s response behavior to interspecific individuals. The term interspecific describes organisms of different species.
    2. Gently move the animal to the center of the aquarium.
    3. Obtain an animal of another species that is found in the same natural environment as the first study organism.
    4. If possible, record the species name, common name, sex, and size of each additional test animal.
    5. Gently place this second animal into the same aquarium as the first one.
    6. Write a detailed description of your behavioral observations in Table 3.11.
    7. Remove the second species, and allow the first animal time to rest before continuing on to the next step.
       
  8. Optional: Additional stimuli
    1. Test the animal’s behavioral response to a stimulus of your own choosing. Do not intentionally harm your study organism. Seek the approval of your teacher before proceeding.
    2. Write a predicted response behavior in Table 3.11.
    3. If your teacher approves, conduct your behavior response trial.
    4. Write a detailed description of your behavioral observations in Table 3.11.
       
  9. FURTHER INVESTIGATIONS: Design and complete your own behavioral experiment to address one of the following questions. Write a research proposal and obtain your teacher’s approval before beginning your project.
    1. What is the preferred habitat of your study species?
    2. What is the preferred food of your study species?
    3. How does your study species detect food? Direct physical contact or touch? Chemical cues or scent? Visual cues?
    4. How do members of your study species respond to competitors that belong to the same species? How do they behave with competitors of other species?
    5. For your study species, how does behavior differ between mature adult males and females?
    6. For your individuals within your study species, what are some behavioral adaptations that may improve the chances of survival against predators?
    7. How does your study organism reproduce? What are some behavioral adaptations that may help your organism reproduce?
    8. Does the behavior of your study organism change when it is surrounded with several other individuals from the same species? Does this group of animals exhibit behaviors of its own? Are individuals within the group able to communicate with each other?
    9. For your study species, how do individual behaviors change with organism over the course of the individual’s life history? Or with body size?
    10. Develop your own independent research question on invertebrate behavior.
       
  10. For gastropods: Investigate copper touch
    1. Carefully place polished pennies or copper wire in a circle around the gastropod.
    2. Observe and record the response behavior of the gastropod as it approaches and contacts the copper metal.
    3. Repeat the experiment with non-copper coins and wire.
       
  11. For crustaceans: Investigate respiratory behavior
    1. Fill a pipet with food coloring.
    2. Carefully position the tip of the pipet near the head of the crustacean.
    3. Gently squeeze out a small amount of food coloring into the water.
    4. Observe and record the movement of the colored water around the head and through the crustacean’s gills.
       
  12. For sea cucumbers: Investigate respiratory behavior
    1. Locate the aboral or anus end of the sea cucumber. Observe the opening and closing of the anus. The opening and closing of the anus can be considered one respiratory cycle.
    2. Count and record the number of respiratory cycles completed in one minute. This number is the respiratory rate of the sea cucumber.
    3. Investigate how the sea cucumber’s respiratory rate changes in response to various stimuli, such as those in Part C.

 

Activity Questions
  1. Movement
    1. How did your study organism move?
    2. What anatomical parts are used in its movement?
    3. What is the difference between “movement” and “locomotion” in animals?
    4. Did your study organism complete locomotion? If so, describe it.
       
  2. Locomotion
    1. What are some advantages of locomotive behavior?
    2. What are some disadvantages of locomotive behavior?
       
  3. In this activity, you examined response behavior to a variety of stimuli. How might these experimental stimuli relate to stimuli these organisms might experience in their natural environment?
     
  4. The following questions relate to the probe touch stimulus:
    1. How did your study organism respond to the probe touch stimulus?
    2. How did this touch response behavior compare to the various food response behaviors?
    3. Would you describe probe touch behavior as a defensive action or as a food capture action? Explain.
    4. When might this organism exhibit this same response behavior in its natural habitat?
       
  5. In this activity, you observed a wild animal held in captivity.
    1. How might the behavior of an animal be different in captivity compared to its natural habitat?
    2. What similarities might you suspect in the behavior of captive and wild animals?
       
  6. Critique your own experimental methods. How might you change and improve these experiments for future behavioral research?
     
  7. The live organisms used in this activity were collected from the wild. What are some specific environmental concerns regarding this practice?
     
  8. How do these various response behaviors (Table 3.11) relate to that individual’s chances of survival and reproduction?
     
  9. All animals need to acquire energy, typically through the consumption of food.
    1. What is the difference between “feeding” and “food capture”? Which did you observe today?
    2. Predict the relationship between an animal’s feeding behavior and its body size. What experimental evidence or observations can you present to support your answer?
       
  10. Sensory systems and behavior
    1. What organs did your study organism use to detect the environment around it?
    2. How do these sensory organs relate to the various behaviors of the organism? Locate sensory organs on the live animal, if any.
       
  11. Compare response behaviors across invertebrate taxa.
    1. What are some behavioral similarities between the taxa?
    2. What are some behavioral differences between the taxa?
       
  12. Most of the adaptations discussed in the text are physical features, such as swimming fins and blubber in whales. However, some adaptations are behavioral in nature. Describe at least one behavioral adaptation that might aid in the survival and reproduction of a marine organism.
Exploring Our Fluid Earth, a product of the Curriculum Research & Development Group (CRDG), College of Education. University of Hawaii, 2011. This document may be freely reproduced and distributed for non-profit educational purposes.