7. What is the male's extended phenotype, and give an example of an experimental test of the role of the male's extended phenotype in affecting female choice. Why is it necessary to do such experiments?

A males extended phenotype is a characteristic outside of the male's body that a female chooses on when deciding to mate, i.e. territory size or quality. (3 points)

Total points for mention of an example from class and an experiment design that emphasizes manipulations that are able to tease apart male phenotype characteristics (i.e. male appearance or body size) and the male's extended phenotype (i.e. territory). (14 points - points vary on detail and explanation)

Ex. Females might choose males on the basis of the quality of the male or the quality of the territory that the male secures. Howard (1979) demonstrated that male bull frogs tend to mate with the largest male bull frogs and their is a positive relationship between male bull frog size and the number of females that a male secures as mates. Howard assessed the quality of the male and the male's territory, by tracking the survival of the eggs through to hatching as a tadpole. Such aspects of territory quality can be considered part of the male's extended phenotype.

Another example would be shrikes and lizards jewelry.

Cause and Effect is the key -- answering cause and effect. A female can choose a male on the basis of a number of potential traits, and such male traits might indeed be correlated with one another or indeed, correlated with the female preference per se. It is essential to perform manipulative experiments of the male trait to isolate the effect of a specific male trait on the preferences of females. (3 points)