Reference no: EM132707905

1. In a flock of birds, parents can raise small clutches on their own but can increase their clutch size if they have a helper. You want to see if altruistic behavior is likely to spread. To do this, you observed a male bird that stayed at his birth nest for a year to help raise the offspring of his father and his stepmother (the original mother died) and then built his own nest the following year. You calculated direct fitness (cost) for the male bird by counting the number of offspring he produced in one year and multiplied it by ½ due to the relatedness between parents and offspring. To calculate his indirect fitness (benefit), you took the total number of offspring produced in his birth nest by his father and stepmother in Year 2 and multiplied it by ½. To determine if this altruistic behavior would spread you subtracted the cost from the benefit to determine whether it was greater than 1. What did you do wrong?

2. What are the characteristics of eusociality and how do they differ from facultative sociality? How does this affect the likelihood of altruistic behavior in the two groups?