Final answer:
Parental investment theory explores the roles and investment of parents in the care of their offspring, considering factors such as the number of offspring and the relationship between fecundity and parental care.
Step-by-step explanation:
Parental investment theory explores the roles and investment of parents in the care of their offspring. It examines how organisms allocate energy and resources to ensure the survival and successful reproduction of their offspring. This theory considers factors such as the number of offspring, risk of population increase, and the relationship between fecundity and parental care.