Conscientiousness and Openness: Tracing our evolutionary heritage
While the Big 5 factor “extraversion” is the most widely known personality factor, conscientiousness and openness are even more interesting as they show a variety of correlations that have implications for modern life. Extraverts tend to be happier than introverts, have better social networks, retire later from the workforce and have more romantic partners during their lifetime. These are certainly some impressive correlations. However, conscientiousness and openness have correlations that are at least as impressive.
High conscientiousness is correlated with:
- Higher academic and financial success
- Solid work ethic
- (social) conservative political orientation
- More stable romantic relationships and fewer divorces
- Health outcomes and Longer lifespans and health outcomes
High openness is correlated with:
- Lifetime learning and knowledge
- Creativity and to a certain extent with intelligence
- Liberal political orientation
- Higher intake of healthy foods like fruit and vegetable, less meat
- Higher risk for psychosis and mental health problems
These are by far not all interesting correlations. Political orientation alone comes with a host of different values and attitudes, like a tendency towards xenophobia or xenophilia or traditional vs progressive values (e.g. gender equality).
What is the evolutionary origin of these two personality factors? Each factor is a bundle of traits or facets:
Conscientiousness includes the facets or sub-traits of being achievement-oriented, cautious, dutiful, orderly, self-disciplined, and prone to self-efficacy.
I have argued that high conscientiousness only evolved late in human evolution, i.e. with the advent of horticulture/agriculture. Basically, all the facets are indications:
Achievement orientation (industriousness): farmers had to work more and harder for subsistence than hunter-gatherers. Cautious and detail-oriented work habits: farming required long routine work with a constant focus on many details (sowing, weeding, harvesting, etc.). Orderliness is all about changing the environment for your needs rather than adapting to an environment. Self-discipline and delayed gratification had never been this important in hunter-gatherer life, who immediately consume whatever they have to eat. For early farmers eating the seeds rather than showing them would have been detrimental. Walter Mischel’s famous Marshmallow experiment has shown how much even little children differ in their ability for delayed gratification. There really isn’t that much difference between marshmallows and grains from an evolutionary point of view. Dutifulness: a lot of farming effort, especially irrigation farming, had to be organised hierarchically rather than in an egalitarian hunter-gatherer way. Again, it was of vital importance that farmers fulfilled their position in a hierarchy and followed orders without too much protest. Finally, high conscientiousness and high disgust go together. This trait helped sedentary farmers fight higher numbers of pathogens.
Openness involves six facets, or dimensions: active imagination (fantasy), aesthetic sensitivity, attentiveness to inner feelings, preference for variety (adventurousness), intellectual curiosity, and challenging authority (psychological liberalism).
By now it should be clear that a lot of farmer traits are incompatible with the nomadic lifestyle of egalitarian hunter-gatherers. Openness predicts and preference for variety, which is exactly what we would expect for nomadic people (hunter-gatherers or pastoralists). Sensitivity: hunter-gatherers are highly in tune with their environment and experience themselves as a part of nature rather than the humans vs nature experience of farmers. Imagination is highly important for hunters when tracking animals as they have to imagine several possibilities simultaneously. Not only do hunters infer what kind of animal they are tracking, but also details, like its age, speed, direction, state of exhaustion, etc. Hunter-gatherers living in our “farmer” world would also frequently challenge authority as they are highly egalitarian and would accept only temporary leaders based on high competence.
Personality factors provide a map of our evolutionary origin. Check out my book for more background information on mapping human nature: