This chapter is primarily concerned with how social interactions among individuals evolve as a part of reproductive strategies, uses molecular techniques to reveal some of the hidden complexities of the Seychelles warbler system, and explains the evolutionary significance of the results across all taxonomic boundaries. These studies show that the Seychelles warbler can be a model system to investigate the questions in behavioral, evolutionary molecular ecology. The fact that both dominant and subordinate females may lay eggs within the nest adds complexity to the issue of sex allocation that needs to be explored. In light of subordinate maternity and extra‐pair paternity revealed by the studies described in the chapter, the chapter assesses the long‐term inclusive fitness consequences of sex allocation to confirm its adaptive nature. Fitness benefits may differ (or conflict) between male and female, one needs to investigate experimentally the fitness consequences accrued by both members of the breeding pair.