What do they study

Study of traits shaped by natural selection
No formal distinction from evolutionary biology
Example psychological traits/behaviors: jealousy, homicide, male promiscuity
What was its evolutionary function of jealousy? (studied by Bus)
- Mate-guarding behavior. If you spend lots of resources/time on offspring, you want to make sure they’re yours.
- Observed in primates standing in front of their mates and chasing off all other suitors
How to validate this hypothesis?
- There are two claims to be tested empircally :
  1. The existance of jealous mental states caused people to leave more offspring
  2. Those offspring inherited the tendency to have jealous mental states

Criticism

Couldn’t you just make up a narrative for any trait?

It is fair to accuse EP of making ‘just so’ plausible stories.
Though unfair to say there is anything wrong with that, even if it can be used to justify any conclusion.
Hypotheses (in general) have this feature as well.
- We could’ve come up with a hypothesis for why the sky is black.
EP has been unfairly criticized for ‘just so’ stories when they are widespread in science.
However need to be careful to resist seduction of hearing a ‘just so’ story and think that the hypothesis is confirmed.
Admits that EP are more likely to succumb to this seduction over other fields
The narrative ought just the beginning of a research programme to verify it.

Can’t do tests on humans (ethical reasons, lifespan too long to measure reproductive success)
Mental states do not leave fossils
Need to make claims about proto-humans.

There is tendancy of (moral/political/mind) philosphers to bring in evolution as a skyhook for their theories
It’s not usually a core argument, but it’s used as support
They usually not good support because EP is almost never empirical
Furthermore, lots of evidence of evolutionary selected features that are selected for ‘arbitrary’ reasons, unrelated to flourishing
- E.g. female preferring mate to have a particular spot pattern/chirp just
  due to ‘how they’re wired’ / randomness
- So evolutionary fitness of a moral trait is not a good supporting argument by itself