Cultural Bias: Reward/Need Satisfaction Theory doesn't account for cultural or gender differences. Women may focus more on the needs of others in some cultures.
Evolutionary Explanation: Romantic love allows us to focus courtship energies on specific individuals. Love at first sight speeds up the mating process.
Cultural Bias: 'Economic' theories only apply to Western cultures and to short-term relationships, where people are more concerned about give-and-take and less about security e.g. students in Western societies.
Real-world Application: A primary goal of relationship therapy may be to increase the proportion of positive exchanges and reduce negative exchanges.
Real-World Application: The Couples Coping Enhancement Training (CCET) programme aims to sensitise couples to issues of equity and respect within their relationship and to improve communication and problem-solving skills.
Ethical Issues: Vulnerability of participants is an issue as revisiting breakdown may be difficult for them. Issues of privacy as research is of an intensely personal nature.
Gender Bias: Men could never have evolved the desire for a variety of sexual partners without the participation of willing females. Females may also gain benefits from short term mating, such as mate switching.
Non-Human Research: The two most closely related species are chimpanzees and bonobos. Both show little or no paternal investment. This may mean paternal investment evolved because of cultural learning.
Reductionist: Explanation of paternal investment based on evolutionary factors is limited as men's behaviour depends on personal and social conditions e.g. quality of relationship with the mother, characteristics of child and parent.
Influence of Childhood
Non-Human Species: Experiments of social deprivation with human children are unethical. Research on rhesus monkeys reared with inadequate peer contact showed inappropriate social and sexual behaviour as adults.
Determinism: Research may appear to suggest that childhood experiences have a fixed effect on adult relationships, yet multiple studies found plenty of cases where participants experienced happy adult relationships.
Real-World Application: US Romantic Comedies create a warped sense of the 'perfect' relationship and this could have an adverse effect on the satisfaction of adolescents' future relationships in the US and UK. For instance, in the portrayal of 'love at first sight', whereas in real life love and commitment may take years to develop.