Question

Kin selection r = the coefficient of relatedness between two individuals The coefficient of relatedness is the probability that a particular allele is present in the two individuals being compared. Coefficient of relatedness Think about these questions: Would you lend your life savings to your sibling if they desperately needed the money? What about your cousin? Consider your answers as you go through this exercise. 1. What is the coefficient of relatedness between you and your parent, i.e., roffspring-parent? 2. What is the coefficient of relatedness between you and your nephew, i.e., runcle/aunt-nephew? 3. What is the coefficient of relatedness between you and your grandparent, i.e., rgrandparent-grandchild? 4. What is the coefficient of relatedness between you and your brother, i.e., rsiblings? 5. What is the coefficient of relatedness between you and your cousin, i.e., rcousins? Hamilton’s rule Genes that contribute to altruistic behavior are favored by natural selection if Hamilton’s rule is met. Hamilton’s rule: r B > C r = the coefficient of relatedness B = the benefit to the recipient C = the cost to the altruist Questions For Q1 & Q2, assume that each survivor has 2 offspring and work out B and C based on the offspring. 1. Should I rescue my sibling who is drowning if there is a 25% chance that I will drown in the process? 2. Should I rescue my 2 siblings that are drowning if there is a 75% chance that I will drown in the process? 3. Suzy the ground squirrel sees a hawk. If Suzy makes an alarm call, she is certain to be eaten but nearby sisters are certain to survive. If, instead, Suzy dives into her hole, she is certain to survive, but her sisters are certain to be eaten. For these questions, base B and C on the ground squirrels that die or are saved. a. Should Suzy sound the alarm if she can save 1 sister? Explain. b. Should Suzy sound the alarm to save 3 sisters? Explain. c. Should Suzy sound the alarm to save 3 cousins? Explain.

Answer 1