That's true to.
One thing I noticed was that the people they measured, were younger adults, which have been shown to not have complete brain structuring until around 25 years old.
If that's the case, the fear portions of the brain not completely developed would make sense, as young people are commonly known for their lack of inhibition.
I think there was also an element of large numbers of social connections or something as well.
In kicking the idea of some genetic phenomenon at play around with friends quite a bit over the years we came to some similar but decidedly different conclusions than the study above.
We noted that while many conservative positions appear to be based on fear, on further consideration we decided it was more a powerful "rally round the flag, the huns are coming" response.
This fits our overall conclusion, that the difference in life approaches is evolutionary/genetic.
The "risk taking" element fits too. Mastadons are HUGE. Potatoes....not so much.
Its actually kind of amazing how well this model fits. How plausible it seems when various factors are run through it.
And its perfectly scientifically possible.
Hunter-gatherer and agricultural-pastoral lifestyles would select for different traits/behaviors.
12,000 years is plenty of time to do it.
When you consider history, most of the time there have been three basic groups that breed pretty much inclusively:
Aristocracies
Peasantries
Frontier/explorer types
This would tend to imply that there are possibly THREE subspecies.
Or two with an additional subset.
Tons of fun brain exercise down this rabbit hole!:2wave: