Group Behavior

Lab Manual
生物学
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Lab Manual 生物学
Group Behavior

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07:33 min

January 29, 2019

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  1. The Hawk-Dove Game
    • NOTE: In this activity, you will play the hawk and dove game with a single partner and then with multiple partners to observe hypothetical costs and benefits of the antagonist or cooperative behavior respectively.
    • Before the activity starts, review the cost-benefit table so that you understand how to score the game. Click Here to download Table 1
    • HYPOTHESES: The experimental hypothesis for this exercise could be that the dove strategy will become more frequent between repeated partners, and the hawk strategy will become more frequent when interactions are with a variety of partners. The null hypothesis could be that there will be no change in strategy over time with repeat or different partner combinations. NOTE: Benefit can be determined by looking at the left column and choosing the row that corresponds to the card you played. The box that corresponds to the choice of your partner can be found in the top row. For the purposes of this game, B equals four and C equals three. So depending on the cards played, player one here, which is you, would gain a score of two, four, zero or one half.
    • Collect a set of two game cards.
    • Take out the cards labeled hawk and dove and place them face down on the table or conceal them in your hands.
    • When the instructor gives the signal show either of the two cards to the student sitting across from you. Try to strategize how to receive the highest benefit from every interaction on your own but do not communicate with your partner.
    • In the Single Partner Recording Table (Table 2) provided by your instructor, note the cards played as well as the benefit you received for that round.
    • Repeat showing cards to the same partner and determining benefit on your instructor's signal for a total of 15 rounds.
    • At the end of those rounds, the student with the highest total benefit value was determined to be the “winner”, or the most fit.
    • As a class, determine the percentages of hawks and doves played as well as the average benefit received for each round, using this formula: Class average benefit=(sum total benefit)/(number of players)
    • For the second game, and then for each round of play, one row of students should rotate to their right, leaving all players with a new partner.
    • Continue playing for 15 rounds or until students end up back in their starting positions, recording the data in the Multiple Partner Recording Table (Table 3) given to you by your instructor.
    • For each round, determine the percentages of hawks and doves played that round, as well as the average benefit received.
  2. Cheating and Cooperation Exercise
    • NOTE: In this activity, you will exchange benefits, represented by colored or similar items, with your classmates. In this simulation, a cheater is defined as a person who gives fewer benefits than they receive. During this activity, you will observe the frequency of cheating behavior over time.
    • HYPOTHESES: The experimental hypothesis is that cheaters will receive fewer benefits over time and cooperators will continue to provide equal benefits to one another. The null hypothesis is that the frequency of cheaters and cooperators does not change over time.
    • Each person should collect beads of one color to represent a tangible benefit, as well as one paper bag and a three-ring binder.
    • Get into a group of three so that all members have objects of the same color.
    • Now find another group with a different color to pair with. In each round, partners will exchange benefits without knowing what they are receiving from their partner and without discussion within their group. NOTE: Benefits of a different color from your starting color are worth twice as much.
    • Turn face to face with a member from the other group while still being able to conceal the objects in your possession. TIP: Setting up a screen using a notebook or sitting behind a desk can be helpful here.
    • When given a signal from the instructor, place zero to two benefits into the paper bag and pass it to your partner.
    • Simultaneously, receive the bag from your partner and then remove the benefits from the bag.
    • Make a note of how many benefits you gave away and how many you received in the Cheating and Cooperation Table (Table 4) provided by your instructor.
    • Turn to a new member from the other group and repeat the exchange.
    • Rotate through all of the members of the other group for as many rounds as the instructor determines – which will not be revealed until the game ends so as not to alter player behavior.
    • Once the game has ended, note for each round in the cheating and cooperation table whether you gave more than your partner, received more from them or if you gave the same amount.
    • Now total up all of the benefits in your possession, with benefits you've received from the other group being worth twice as much.
    • For each round, the whole class should total up the number of cheaters – with cheaters defined as those who gave less than they received.
  3. 結果
    • For both the single partner hawk-dove game and the multiple partners hawk-dove game, use the whole class data to plot the percentages as two separate lines – one for the percentage of hawks, and one for the percentage of doves, for each of the 15 rounds.
    • Take note of whether the cards played changed as more rounds were played.
    • Manipulate the values for B and C to see if you can find the point at which values of B and C would render the hawk strategy no longer effective (this would be the point when there is no benefit to choosing the hawk strategy over always choosing the dove strategy).
    • As a class, use the data from the cheating and cooperation activity to make a graph showing the percentage of rounds each individual player cheated versus the amount of benefits they ended with.
    • Consider whether it is better to be a cheater or a cooperator in this scenario and discuss as a class what makes this scenario different from the hawk-dove game.
    • Now, use the class data to graph the percentage of cheaters against the number of rounds, and look for any trends over time.
    • Consider which type of strategy would most likely evolve in a setting where partners interact repeatedly.
    • Then, note which tactic might be beneficial for a species that relies on cooperation.
    • Discuss as a class what would likely happen if you increased or decreased the relative value of the benefits you receive.