Materials Included In Kit

Additional Materials Required

Prelab Preparation

Activity A. Opposable Thumbs

1. Photocopy the heart template, enough for two hearts per student. Cut apart the hearts (¼ sheet).
2. Provide two sheets of scratch paper for each student. This will be used in the task of making a paper airplane.
3. When grouping students, make sure one partner is wearing a gym shoe with laces or provide one gym shoe with laces per station.

Activity B. Stereoscopic Vision

1. Construct three shadowless boxes for Activity B by assembling each die-cut box and affixing one sheet of black construction paper to each inside face of the box. Do not trim paper. Orient the box at each station so the opening is facing the test subject and the box is wider than it is tall.
2. Place four Styrofoam balls in each box.
3. Place four washers near each box. Students can place Styrofoam balls on the washers to hold the Styrofoam balls in place (see Figure 5).
   {11337_Preparation_Figure_5}

Activity D. Feathers

1. Cut the netting in 9" lengths. Each lab station should have two pieces of netting, one for each 1-liter plastic bottle.
2. On the teacher lab station, a hot water station is needed for students to fill the 1-liter plastic soda bottles. Each group will need 1900-mL of hot water (65–70 °C) to pour into their bottles, about 6000-mL of water per group rotation. Have hot water ready for the first groups, and while students are timing, begin heating another 6000-mL of hot water for the next groups.

Safety Precautions

Wear chemical splash goggles and heat-resistant gloves when handling hot water. Remind students to wash their hands thoroughly with soap and water before leaving the laboratory. Please follow all laboratory safety guidelines.

Disposal

All items may be saved for future use or disposed of in the regular trash.

Lab Hints

• Enough materials are provided in this kit for 24 students working in pairs or for 12 groups of students with three workstations set up for each activity. Each activity will take between 20-25 minutes with setup, data collection and resetting. Three 50-minute class periods will be enough for students to collect data and work on prelab and post-lab questions.|Each activity is self-contained and may be completed in any order.
• For Activity A, Opposable Thumbs, helping the students tape their thumbs properly will ensure they are not able to use their thumbs and minimize masking tape waste. It may be easier to tape the thumb to the palm. Make sure the thumb is covered completely.
• For Activity B, Stereoscopic Vision, a distance of 10–20 feet between partners is required. Try to set up each station allowing for unobstructed views between each partner, ideally along the perimeter of the lab or classroom. Showing students how to move the washer—toward and away from the partner instead of side to side—is important as stereoscopic vision permits depth perception.
• For Activity D, Feathers, have several hot plates ready with beakers of hot water, near 65 °C. Each group needs 1900 mL of hot water. As the first three groups take the hot water, immediately start heating more water for the next rotation of student groups. Alternately, a laboratory microwave may be used to heat the water. Another option is to use a large coffee percolator. Refill the coffee maker with hot tap water immediately after dispensing. Allow the dispensed water to cool a few minutes, as it will be hotter than 65 °C.
• The bottle without feathers is the control and the water temperature will drop more quickly than the bottle with the feather layers. If students layer the feathers with the downy feathers closest to the bottle and cover them with semiplume feathers, the water temperature can stay fairly constant for 10 minutes or more.
• Place paper towels or absorbent lab mats around the plastic soda bottles in case of overflow.
• If time allows, run activity D, Feathers, for 15–20 minutes. A greater difference in temperature between the control and the experimental setups will result. In our testing, the end temperature for the bottle with feathers was 70 °C and the bottles without feathers was 64 °C.

Teacher Tips

• This activity can be used as an introduction or as reinforcement for concepts of adaptation and natural selection. The students will collect data to demonstrate that survival is improved with adaptations.
• Other activities available from Flinn Scientific may further the concepts of adaptation and natural selection. These include Stick Bug Survival and Natural Selection (Catalog Nos. FB1609 and FB1989). Challenge your students by incorporating STEM into your curriculum with FB2130 Beaks—Flinn STEM Design Challenge and FB2129 Fish Fitness—Flinn STEM Design Challenge.

Answers to Prelab Questions

1. Describe how adaptations are obtained. What criteria must a trait meet to be considered an adaptation?

   Adaptations are inherited from parent to offspring. An adaptation improves survival and reproduction.

2. Infer the purpose of the following adaptations.
   1. Lemon sharks can detect one drop of tuna oil in 25 million drops of water.

      Lemon sharks feed on tuna, so being able to detect their presence makes the lemon shark more successful in locating and killing the prey.

   2. A male duck-billed platypus has spurs on the hind feet that release venom.

      The venomous spur on the heel of the duck-billed platypus is used when competing for mates or territories and as a defensive weapon.

3. In your own words, explain how natural selection affected the peppered moth population in England.

   The peppered moth population prior to the Industrial Revolution was primarily the light-colored variety, which allowed for camouflage with light-colored tree bark. However, after the Industrial Revolution, the buildup of dark soot on tree bark meant the light-colored moth was no longer camouflaged by the tree bark and was easily spotted and consumed by predators. The dark-colored variety increased in the population quickly since the moths were better camouflaged by the polluted bark.

Activity A. Opposable Thumbs

1. What is an opposable thumb?

   An opposable thumb is able to turn back against the other four fingers.

2. Predict the advantage of having opposable thumbs.

   An opposable thumb allows the ability to grasp and hold objects like tools.

Activity B. Stereoscopic Vision

1. Close your right eye, hold your thumb up at arm’s length and align it with a distant object. Now, simultaneously open your right eye and close your left eye. Describe what you see.

   With the right eye closed, I see my thumb in the center of my field of view. When I close my left eye, my thumb appears to shift to the left.

2. Predict the advantage of stereoscopic vision.

   Stereoscopic vision allows for depth perception, which allows an organism the ability to determine distance.

Activity C. Camouflage

1. Predict the advantage of camouflage.

   Camouflage helps an organism to blend in to the surroundings, which allows it to be hidden from predators or prey.

2. Give an example of how humans use camouflage to their advantage.

   Humans use camouflage when hunting to hide from the animal they are hunting or in combat to hide from the enemy.

Activity D. Feathers

1. Read through the Procedure. Predict how feathers will affect the water temperature.

   Down feathers allow air to be trapped, so the water temperature should be held fairly constant.

2. Based on the Background about feathers, how should the feathers should be arranged around the bottle?

   Feathers with a soft, fluffy appearance (down) should be placed closest to the plastic soda bottle and then covered with feathers that have both soft and more rigid features.

Sample Data

Activity A. Opposable Thumbs

Data Table A

Activity B. Stereoscopic Vision

Data Table B-1 Data Table B-2 Activity C. Camouflage

Data Table C Activity D. Feathers

Data Table D

Answers to Questions

Activity A. Opposable Thumbs

1. How does an opposable thumb assist in everyday tasks?

   An opposable thumb simplifies and shortens tasks due to the ability to grasp objects.

2. Consider the time it took to complete a task with the use of your thumbs versus the time without thumbs.
   1. Which tasks, if any, took more time without the use of your thumbs?

      All the tasks except folding the paper airplane took more time without the use of thumbs.

   2. If any of the times for a task with and without thumbs were similar, how did the quality of the task compare?

      In making the paper airplane, the times to complete the task were very similar; however, the folds were not as crisp and symmetry was lacking without using thumbs.

3. How does an opposable thumb give humans an advantage over other organisms?

   Humans are able to use tools. This allows for more skilled tasks to be completed.

4. When your thumbs were taped, were you able to behaviorally adapt at all? Explain.

   Tasks took longer and required more focus while the thumbs were taped. However, changing the approach, especially with hooking and unhooking paper clips made the task easier. When hooking the paper clips, sliding the paper clip to the edge of the table made grasping them much easier. Also, carefully attaching them together, being aware that they needed to be detached, made that part of the task simpler.

Activity B. Stereoscopic Vision

5. How does binocular vision differ from monocular vision?

   Binocular vision occurs when two eyes face forward, which results in each eye observing slightly separate images that are superimposed into one image. This allows for the ability to judge depth and distance. Monocular vision limits depth or distance vision, but gives the organism a larger field of view, as each eye observes a different scene.

6. Use the description of monocular vision and binocular vision and the activities performed to answer the following questions:
   1. Which types of organisms would benefit from monocular vision?

      Monocular vision gives an organism a large field of view, so a prey species constantly on the alert for predators would benefit from such vision.

   2. Which types of organisms would benefit from binocular vision?

      Binocular vision gives an organism a smaller field of view, but allows the organism the ability to judge depth or distance. This allows a predator a more precise attack by being able to judge the distance to prey.

7. Use the data from the two activities to determine when you most accurately judged distance.

   Dropping the washer into the cup and determining which ball was closer was most accurately determined with normal vision, using both eyes.

8. Based on the two activities, infer the advantage of stereoscopic vision for humans.

   Stereoscopic vision allows for the ability to judge distance and depth perception. This makes everyday tasks, like walking up and down stairs or riding a bike much safer and simpler. It is also beneficial in recreational activities, such as catching or hitting a ball.

Activity C. Camouflage

9. In Activity C, what does each material listed below represent in nature?
   1. Wrapping paper

      Wrapping paper represents the background of habitat of the organism.

   2. Toothpicks

      Toothpicks represent the prey species being hunted.

   3. Partner 1 or Partner 2

      The partners represented the predators hunting prey in the habitat.

10. Which toothpick color was selected most often? Why do you think that is?

    The wrapping paper pattern used in data collection was primarily red and yellow. Blue and green toothpicks were selected most often because they did not blend in with the background and were easily spotted.

11. What is the advantage of camouflage for:
    1. A predator?

       Camouflage allows a predator ability to stalk its prey without being noticed.

    2. A prey?

       Camouflage allows a prey species the ability to blend in with the surroundings or with other prey, which can either cause the predator to not notice the prey or confuse the predator.

12. Suppose that after partner 1 and partner 2 finished selecting toothpicks (20 total trials), each toothpick not chosen was able to “reproduce.” For each toothpick not chosen, another toothpick of that same color was added. After several rounds (generations) of choosing toothpicks and adding more of the remaining colors only, how do you think the population of toothpicks would change? Hint: Use the idea of natural selection from the Background section.

    Based on the concept of natural selection, a population will change due to the adaptations that are best for reproductive success. In this case, the colored toothpicks that were not chosen would survive long enough to reproduce and pass on their genes. The toothpicks that were chosen would not survive long enough to reproduce. Over time, the population would have more toothpicks of the red and white that were rarely chosen and the population of blue and green toothpicks would most likely be greatly reduced or even disappear.

Activity D. Feathers

13. Based on the Background information for Activity D, what types of turkey feathers were used?

    Give evidence for your answer. The feathers are both semiplume and down. The down feathers have an underdeveloped central rachis and the barbs are not connected. These feathers are very fluffy all over. The semiplume feathers are fluffy near the calamus, and have connecting barbicels near the tip.

14. Describe the arrangement you and your partner chose for the feathers around the bottle.

    Student answers will vary with how the feathers were initially arranged.

15. How would you rearrange the feathers if you had time to repeat the activity?

    If able to repeat the activity, students should suggest placing feathers with soft, fluffy down nearest the bottle with semiplume feathers covering. Students may also rearrange feathers to completely cover the bottle, including the neck, thus reducing exposure to outside air.

16. Graph the data for both bottles. Be sure to title the graph, label the x and y axes, include units, and include a key.
    {11337_Answers_Figure_6}
17. Based on the data, what is an advantage of having feathers?

    In this activity feathers act as an insulator and help the organism maintain a constant body temperature.

Teacher Handouts

11337_Teacher.pdf

Introduction

The purpose of an adaptation is to improve the chances of survival. During these activities, see if you can determine how the adaptation does just that!

Concepts

• Adaptation
• Natural selection
• Fitness

Background

An order of insects, Phasmatodea, are commonly referred to as stick insects or walking sticks.

These insects are the ultimate masters of disguise. They are experts at remaining perfectly still in order to resemble a stick, which most predators don’t eat! On windy days, they will swing their bodies back and forth to mimic branches swaying in the wind. But, this isn’t all they do to avoid becoming a meal. Their coloration—vivid green or deep brown—allow them to become almost invisible in the forest habitat they call home. Occasionally though, they may fall into the grasp of a predator, but these amazing creatures are ready. Many will release an unpleasant odor to drive predators away or stiffen their bodies when seized and become rigid, often fooling predators into thinking they are twigs and not a delightful meal. So what are all these disguises and behaviors known as? Adaptations!

Adaptations are inherited characteristics that improve fitness. Fitness is an organism’s ability to survive and reproduce. When organisms survive to reproduce, they pass their genes to the next generation creating healthy, fertile offspring. Natural selection occurs when individuals with a beneficial adaptation survive and reproduce in greater numbers than those without the adaptation. Over time, the entire population will evolve as more and more individuals inherit the adaptation. The peppered moth, Biston betularia, is one of the most chronicled examples of natural selection.

In Manchester, England, prior to the industrial revolution, the light-colored peppered moth, referred to as typica, was the predominant phenotype, while carbonaria, a dark-colored peppered moth was much less common. The coloration of typica allowed for excellent camouflage as many of the trees in England had light-colored bark. The theory is that due to the Industrial Revolution, soot and smoke polluted the light-barked trees causing a dramatic change in the typica moth population in urban areas. The dark bark made the typica moth much easier for predators to spot. Hence, they were unable to survive long enough to produce offspring. However, the carbonaria population increased because the dark bark provided exceptional camouflage. Blending in reduced noticeability by predators and allowed many of the carbonaria moths to reach reproductive maturity.

Activity A. Opposable Thumbs

An opposable thumb is unlike the other four fingers on a human hand, in that it is able to oppose, or turn back, against the other four fingers. The thumb possess similar characteristics to the other fingers, such as having bones with hingelike joints that allow flexion toward the palm and fingertips, and a back surface with hair and a nail. Unlike the other four fingers, the thumb is opposable, has two phalanges (bones) instead of three, and has more freedom in movement in the distal phalanx (finger bone) than the proximal phalanx (see Figure 1). Activity B. Stereoscopic Vision

Why do we have two eyes? Is there an advantage? Our two eyes and their placement on our faces allow for binocular vision, meaning the eyes are used together. In monocular vision the eyes are used separately, as seen in lizards. Monocular vision allows for a wider field of view because the organism can see two completely different scenes, one from each eye. Binocular vision provides an organism the ability to see with stereoscopic vision, which is the perception of a slightly different image from each eye. When the signals from each eye reaches the brain, they are superimposed and processed into a single image, allowing for the ability to judge distance and for depth perception.

Activity C. Camouflage

Camouflage, or cryptic coloration, is basically background matching—making a visible organism indiscernible from the surrounding habitat. The most common example of cryptic coloration is concealing coloration, where the organism resembles its surroundings in coloration, form or movement. The earth-tone colors of a white-tailed deer is an example of cryptic coloration.

Activity D. Feathers

Feathers are complex integumentary appendages—appendages of the skin, such as hair, scales, hooves, nails or feathers. They form in tiny follicles—a cavity composed of small cells—in the outer skin layer and are made of keratin, the same protein found in hair and nails. All feathers have four main features (see Figure 2). The vane (1) is the portion that gives the feather its shape. Barbs (2) are a series of branched filaments that extend from the main shaft or rachis (3). Barbules are microscopic filaments that extend from the barbs and are connected by hooklets or barbicels and create a tight, smooth surface while maintaining the feather shape. Finally, the hollow shaft or calamus (4) is the portion of the feather that inserts into the follicle of the skin. Birds have different types of feathers with different functions. Some are specialized for flight, such as wing and tail feathers. Semiplume and down feathers are found closer to the body. In semiplume feathers, the barbules near the calamus do not have the connecting barbicels, which results in a fluffier texture. Down feathers have an underdeveloped central rachis or none at all and are very fluffy all over. The fluffier portions trap air and help hold in the bird’s body heat.

Experiment Overview

The purpose of this activity-stations lab is to investigate adaptations. Four lab activities are set up around the classroom. Each activity focuses on a simulated example of an adaptation. The activities may be completed in any order.

1. Opposable Thumbs
2. Stereoscopic Vision
3. Camouflage
4. Feathers

Materials

Prelab Questions

1. Describe how adaptations are obtained. What criteria must a trait meet to be considered an adaptation?
2. Infer the purpose of the following adaptations.
   1. Lemon sharks can detect one drop of tuna oil in 25 million drops of water.
   2. A male duck-billed platypus has spurs on the hind feet that release venom.
3. In your own words, explain how natural selection affected the peppered moth population in England.

Activity A. Opposable Thumbs

1. What is an opposable thumb?
2. Predict the advantage of having opposable thumbs.

Activity B. Stereoscopic Vision

1. Close your right eye, hold your thumb up at arm’s length and align it with a distant object. Now, simultaneously open your right eye and close your left eye. Describe what you see.
2. Predict the advantage of having stereoscopic vision.

Activity C. Camouflage

1. Predict the advantage of camouflage.
2. Give an example of how humans use camouflage to their advantage.

Activity D. Feathers

1. Read through the procedure. Predict how feathers will affect the water temperature.
2. Based on the background about feathers, how should the feathers should be arranged around the bottle?

Safety Precautions

Exercise caution when using scissors. Wear heat-resistant gloves and chemical splash goggles when pouring hot water from the beaker through the funnel into the soda bottles. Wipe all spills immediately. Please follow all laboratory safety guidelines. Wash hands thoroughly with soap and water before leaving the laboratory.

Procedure

Activity A. Opposable Thumbs

1. Complete each task listed in Data Table A on the Adaptations worksheet. With your thumbs free, have your partner time how long each task takes using the timer.
2. Record the time required, in seconds, for each task in the data table.
3. Activities may be completed in any order.
4. Repeat steps 1–3 with your partner performing the tasks.
5. Once all activities have been completed by both partners, tape your thumb to your index finger on both hands using masking tape (see Figure 3).
   {11337_Procedure_Figure_3}
6. Repeat each task, for each partner, without the use of your thumbs and record the time in the data table.
7. Reset the station for the next group.
8. If time permits, create your own activity to perform with and then without your thumbs. Fill in the last row in the data table.
9. If you finish early, answer the Post-Lab Questions for Activity A.

Activity B. Stereoscopic Vision

B1

1. Kneel on the floor, approximately 10 feet (3 meters) away from the lab station. Make sure your view is not obstructed.
2. Place the palm of your hand over your right eye and look at the plastic cup at the station.
3. Your partner will hold a washer and slowly move it back and forth (toward you, then away from you, not sideways), over the top of the plastic cup.
4. When you think the washer is directly over the cup, say, “drop,” signaling your partner to release the washer into the cup.
5. Record each attempt as hit or miss, in Data Table B-1 on the worksheet.
6. Perform three trials with your right eye covered, then repeat with your left eye covered, and finally, with both eyes uncovered.
7. Switch places with your partner and repeat steps 1–6.

B2

1. Place the box on the lab station surface about 20 feet (6 meters) away from your partner. Make sure the view is not obstructed.
2. Cover both eyes by placing the palms of your hands over your eyes.
3. Your partner will arrange the four Styrofoam balls so three of the balls are aligned near the back of the box and one is slightly closer (less than 5 cm), to the front of the box.
4. The number of the ball that is out of alignment should be recorded in Data Table B-2.
5. Uncover your left eye only and tell your partner which ball, if any, looks closer to the front of the box. Your partner should not indicate whether the guess is correct, but record your answer in data table B-2 on the worksheet as correct or incorrect.
6. Repeat steps 2–4, rearranging the Styrofoam balls each time, for a total of five trials.
7. Repeat the process, for a total of five trials with your left eye covered.
8. Finally, repeat the process for a total of five trials with both eyes uncovered.
9. Switch places with your partner and repeat the activity.
10. Reset the station for the next group.
11. If you finish the station early, answer the Post-Lab Questions for Activity B.

Activity C. Camouflage

1. Place the wrapping paper on the lab station.
2. Count 10 of each color toothpick. Return unused toothpicks to the box.
3. Turn away from the wrapping paper while your partner randomly spreads the colored toothpicks onto the wrapping paper.
4. When your partner says, “Go,” turn around and pick up the first toothpick seen.
5. Record the color chosen in Data Table C on the worksheet. Do not return the toothpick to the wrapping paper.
6. Repeat steps 3–5 for 10 trials. Your partner should mix up the toothpicks on the wrapping paper after each trial.
7. Switch places with your partner, collect all the toothpicks used in the activity and repeat steps 3–6.
8. Reset the station for the next group.
9. If you finish the station early, answer the Post-Lab Questions for Activity C.

Activity D. Feathers

1. Place a piece of netting over each 1-L plastic bottle.
2. Using the turkey feathers, cover one of the plastic bottles with feathers by sticking the rachis under the netting.
3. Place clay around each thermometer, thick enough to fill the mouth of the bottle (see Figure 4). Test to ensure the thermometer is secure and the entire mouth of the bottle is covered. Remove the thermometers and clay and set aside.
   {11337_Procedure_Figure_4}
4. Using the funnel, fill each plastic bottle with 950 mL of hot tap water. Exercise caution when pouring the hot water.
5. Place thermometers with clay into the mouths of the bottles making sure no heat or water vapor is allowed to escape. Record the initial temperature in data table D on the worksheet.
6. Record the temperature of each bottle every minute for 10 minutes.
7. Remove the thermometers, clay and feathers from the bottles. Empty the water from the bottles into the lab sink.
8. Reset the station for the next group.
9. If you finish the station early, answer the Post-Lab Questions for Activity D.

Student Worksheet PDF

11337_Student.pdf