I'm curious about rather the definition of 'normal', as it affects koinophillia & mate choice, is something instinctual or learned. To clarify I'm not asking if koinophillia itself is instinctual (I take that for granted), but instead the definition of what constitutes 'normal' vs 'abnormal' for a species which drives instinctual attraction via koinophillia.
Basically, does the definition of normal get affected by those around an individual as they grow and/or select a mate? Can a trait that would be considered abnormal for a species be considered accepted or attractive if it is common amongst a small subset that the individual spent time in? For instance, has any study be done in which an animal grew up among a large number of 'abnormal' phenotype animals to see rather the would later be drawn to mates that look like the peers they were raised around or the more normal appearance for their species?
In fact I'm particularly interested in the case of humans. Does anyone know if koinophillia and attraction is affected by the environment one is raised in? For example if someone was born in an isolated island where their populations physical features were rather unique and there was limited genetic variation/gene flow from outsiders but was raised in a family/community of people on the other side of the world with very different physical traits has a study been done to indicate rather they are more likely to be attracted to individuals from their home island, individuals that look like the community the were raised in, or no strong indication either way?