Two females in a muriqui group have each given birth to 6 offspring. One of these “mega-moms,” BS, has given birth to 5 daughters and one son. Her oldest daughter, BR, has a daughter of her own. The other mega-mom, NY, has given birth to 2 daughters and 4 sons. Using this information, answer the following questions:
Which individuals represent BS’ inclusive fitness?
What is the difference between BS’ and NY’s inclusive fitness to date?
What would be the difference between BS’ and NY’s current inclusive fitness if two of NY’s sons had fathered one offspring each?
Sample Answer
Sample Answer
The individuals that represent BS’ inclusive fitness are:
BS herself
Her 5 daughters
Her son
Her granddaughter (BR’s daughter)
The difference between BS’ and NY’s inclusive fitness to date is as follows:
BS has given birth to a total of 6 offspring, including 5 daughters and 1 son.
NY has given birth to a total of 6 offspring, including 2 daughters and 4 sons.
Therefore, to date, both BS and NY have the same number of offspring, but the composition of their offspring differs.
If two of NY’s sons had fathered one offspring each, the difference between BS’ and NY’s current inclusive fitness would be as follows:
BS would still have 6 offspring, including 5 daughters and 1 son.
NY would have 8 offspring, including 2 daughters and 6 sons.
Therefore, if two of NY’s sons had fathered one offspring each, NY would have a higher inclusive fitness than BS.
