Personalities are inherited. Identical twins separated at birth are statistically more similar than fraternal twins.
The human population has almost zero genetic variation, and there is significant mixing so variations do not systematically cluster. Therefore, it seems unlikely that subtle personality differences are due to genetic variation.
My hypothesis is that animal personalities are encoded in epigenetic changes.
This allows personalities to be inherited, crossover, and evolve. Life experiences can induce epigenetic changes, which allows animals to reliably adapt in a single generation. All of this without requiring any genetic variation. A population of clones could have diverse personalities stored in their epigenome.
This is also just not really true. Natural Selection (as opposed to genetic drift) can maintain genetic variations especially for things like personality, due to the fact that “optimal” behavioural strategies depend on what others are doing. Any monoculture of behavioural strategies is typically vulnerable to invasion by a different strategy. The equilibrium position is therefore mixed. It’s more common for this to occur due to genetic variation than due to each individual using a mixed strategy.
Furthermore, humans have undergone rapid environmental change in recent history, which will have selected for lots of different behavioural traits at different times. So we’re not even at equilibrium.
Personalities are inherited. Identical twins separated at birth are statistically more similar than fraternal twins.
This is unclear: are you saying that identical twins separate at birth are more similar than fraternal twins who are raised together (therefore suggesting nature > nurture)? Or that identical twins separated form each other at birth are more similar to each other than fraternal twins separated form each other than birth? (Only suggesting that nature > uhhh less samey nature).
I would also really like to read the abstracts of all the papers that you’re alluding to here because they sound like some quite fantastic claims.
Compare like-to-like: separated identical twins to sepaparted fraternal twins.
I think the best introduction to the topic would be this lecture, which is mostly about all of the problems with separated twin studies. Identical twins starts at 37 minutes.
These two facts seem incompatible:
Personalities are inherited. Identical twins separated at birth are statistically more similar than fraternal twins.
The human population has almost zero genetic variation, and there is significant mixing so variations do not systematically cluster. Therefore, it seems unlikely that subtle personality differences are due to genetic variation.
My hypothesis is that animal personalities are encoded in epigenetic changes.
This allows personalities to be inherited, crossover, and evolve. Life experiences can induce epigenetic changes, which allows animals to reliably adapt in a single generation. All of this without requiring any genetic variation. A population of clones could have diverse personalities stored in their epigenome.
No need to invoke epigenetics, the answer is that 2 is false. Who is claiming 2 to be the case?
Humans clearly have large genetic variation in physical traits, why would mental traits be an exception?
I think a better argument than #2 would be that evolution tends to remove genetic variantions.
This is also just not really true. Natural Selection (as opposed to genetic drift) can maintain genetic variations especially for things like personality, due to the fact that “optimal” behavioural strategies depend on what others are doing. Any monoculture of behavioural strategies is typically vulnerable to invasion by a different strategy. The equilibrium position is therefore mixed. It’s more common for this to occur due to genetic variation than due to each individual using a mixed strategy.
Furthermore, humans have undergone rapid environmental change in recent history, which will have selected for lots of different behavioural traits at different times. So we’re not even at equilibrium.
This is unclear: are you saying that identical twins separate at birth are more similar than fraternal twins who are raised together (therefore suggesting nature > nurture)? Or that identical twins separated form each other at birth are more similar to each other than fraternal twins separated form each other than birth? (Only suggesting that nature > uhhh less samey nature).
I would also really like to read the abstracts of all the papers that you’re alluding to here because they sound like some quite fantastic claims.
Compare like-to-like: separated identical twins to sepaparted fraternal twins.
I think the best introduction to the topic would be this lecture, which is mostly about all of the problems with separated twin studies. Identical twins starts at 37 minutes.
Weird Synchronicity. I literally started reading “Why Don’t Zebras Get Ulcers” last week.