The science may be ripe for a “killer app” project to resolve, once and for all, the criticisms of evolutionary psychology as not a part of science and just a collection of un-provable “just so stories”. Just so stories, which typically explain just one thing, lack sufficient explanatory power and utility to be confirmable as provisionally true in science.
People familiar with the field understand such criticisms are based on misconceptions. I recommend Edward Clint‘s piece on “Science denialism” which provides a good overview with bountiful references.
As Clint describes, some unscientific claims have been made by a few people in the field. However, in my view, perhaps the most foolish and damaging errors regarding evolutionary psychology’s credibility as science have been nonsensical moral implications proposed by people outside the field. As described by Clint, these include silly claims such as “science implies rape is moral because it is natural”.
A “killer app” for evolutionary psychology would be an application that would make evolutionary psychology a confirmed “must have” part of science. An understanding of morality as an evolutionary adaptation seems uniquely suited for bounding over the two pronged barrier to full acceptance: just so story accusations and false moral implications.
Most importantly for the science of the matter, there is the potential for a much larger and more culturally useful volume of explanatory power than any other single adaptation or set of psychological adaptations I can think of. Moral behavior is what enables us to be such successful social creatures and is one of our most interesting and distinguishing characteristics. Such a volume of explanatory power will overwhelm any “just so story accusations”.
Morality as an evolutionary adaptation simultaneously explains the selection forces responsible for a host of puzzling aspects (perhaps all puzzling aspects) of both human ‘moral’ biology and past and present enforced cultural norms (moral standards).
For example, morality as an evolutionary adaptation identifies the selection forces responsible for the biology underlying our ‘moral’ emotions such as empathy, loyalty, guilt, shame, indignation, and moral disgust. The same selection forces are also responsible for the remarkable biology underlying our moral intuitions that, shaped by experience such as experience with cultural norms, determines when and with what intensity these emotions and the behaviors they motivate are triggered.
Morality as an evolutionary adaptation also explains the primary selection forces for virtually all past and present enforced cultural norms (moral standards), regardless of how diverse (such as in who deserves moral regard and who does not), contradictory (homosexuality is or is not immoral), and bizarre (eating shrimp, trimming your beard, or not being circumcised are immoral).
What are these selection forces? There is strong evidence that the universal selection forces for all ‘moral’ behaviors are the benefits of altruistic cooperation in groups. Our ‘moral’ biology was selected for the reproductive fitness benefits of altruistic cooperation. Past and present enforced moral standards were selected for by whatever benefits of altruistic cooperation that people found attractive (not necessarily including reproductive fitness).
Most importantly for cultural utility, this project to understand morality could provide the factual knowledge needed to rationally choose the underlying basis for moral codes. That is, choosing the moral codes to enforce that are most likely to achieve the most common goal for enforcing moral codes: increased benefits from living in that society. Note that no “ought from is” or “naturalistic fallacy” errors are committed when factual knowledge from science is used to reveal the most likely way to achieve a goal. Using factual knowledge from science to define a moral code that is most likely to achieve a goal is no more illogical than a farmer using agricultural science to reveal the most likely way to achieve a goal of growing a lot of beans.
Thus silly claims such as “science implies rape is moral because it is natural” are revealed as non-sense since 1) such norms are unlikely to increase the benefits of living in societies and 2) such behaviors are neither altruistic nor likely to increase the benefits of cooperation in groups.
Conclusion
This project could resolve, once and for all, 1) the criticisms of evolutionary psychology as not being part of science, 2) what moral behavior descriptively is as an evolutionary adaption, and 3) what the characteristics are of the moral codes that ought to be enforced to achieve the common goal of increasing the benefits of living in a society.
This project is definitely multi-disciplinary. Revealing what moral behavior is as an evolutionary adaptation requires evolutionary psychology, genetic evolution, cultural evolution, anthropology, and game theory. In addition to these, understanding what specific moral code norms ought to be enforced will also benefit from assistance from psychology and sociology.