Abstract: New research perspectives have started to question variations in female behavior. Specifically, does a female's reproductive success depend on her access to different mates rather than solely to a dominant male? Paternity analyses in a few lekking avian species have confirmed that in lek systems, polyandry is more frequent than expected and therefore, the variance in male reproductive success is much lower than in a uni-male mating system. Consequently, it is assumed that genetic benefits might include greater mean offspring fitness compared to lower values obtained after a single mating. This evidence supports preliminary observations that suggest that some females of the Andean cock-of-the-rock (Rupicola peruviana), a lek breeding bird, may be adopting a polyandrous mating strategy. Basically, females have been thought to follow a single pattern of mating:

1. They visit a lek several times and are engaged in active choice.
2. At the end, they choose the 'dominant’ male.
3. They approach him and they leave the lek together.

These observations have also been supported by a two-year study of this species in Ecuador (Manosalvas 1993). This project aims to:

1. Document the apparent female mating patterns of the Andean cock-of-the-rock (R. peruviana)
2. Collect blood samples that will be used to address three other important objectives of this dissertation research:
   1. Determine patterns of fertilization by males.
   2. Determine whether there is a pattern of female choice from which benefits to females can be inferred.
   3. Determine patterns of relatedness among males in a lek.