An other problem with authors calculs of potential to improve intelligence: let’s suppose, there is a problem in the human brain that reduces IQ by 10 points, and it can be solved by Gene1 or Gene2. Let’s suppose that 99% of humans do not have either Gene1 or Gene2. In this case, the author’s method would show that if we added both Gene1 and Gene2 to the same person, their IQ would increase by 20 points.
A lot of curves are sigmoid. Let’s say there’s a neurotransmitter where having to double the amount of it increases IQ but there are no gains from having four times as much of the neurotransmitter.
There are two genes that both double the production of the neurotransmitter. If both genes individually are +5 IQ both genes together don’t give you +10 IQ.
It would even be possible that overproduction of that neurotransmitter produces problems at 4x the normal rate but not a 2x the normal rate.
When it comes to chicken and their size I would expect the relationship of there being two genes that both increase muscle production to be happen more frequently than for intelligence.
If you have genetic mutations that increase intelligence without cost evolution works to spread them through the whole population. If you have wild chicken for whom a given size is optimal there’s no strong selection pressure to get rid of all the +x or -y size genes from the gene pool.
One way to look into this would be to see how many of the genes that increase physical size more when there are two copies of the gene compared to how many genes increase intelligence more when there are two copies of it.
And how many genes increase size/intelligence with one copy but decrease it with two copies.
An other problem with authors calculs of potential to improve intelligence: let’s suppose, there is a problem in the human brain that reduces IQ by 10 points, and it can be solved by Gene1 or Gene2. Let’s suppose that 99% of humans do not have either Gene1 or Gene2. In this case, the author’s method would show that if we added both Gene1 and Gene2 to the same person, their IQ would increase by 20 points.
I don’t understand your question
A lot of curves are sigmoid. Let’s say there’s a neurotransmitter where having to double the amount of it increases IQ but there are no gains from having four times as much of the neurotransmitter.
There are two genes that both double the production of the neurotransmitter. If both genes individually are +5 IQ both genes together don’t give you +10 IQ.
It would even be possible that overproduction of that neurotransmitter produces problems at 4x the normal rate but not a 2x the normal rate.
When it comes to chicken and their size I would expect the relationship of there being two genes that both increase muscle production to be happen more frequently than for intelligence.
If you have genetic mutations that increase intelligence without cost evolution works to spread them through the whole population. If you have wild chicken for whom a given size is optimal there’s no strong selection pressure to get rid of all the +x or -y size genes from the gene pool.
One way to look into this would be to see how many of the genes that increase physical size more when there are two copies of the gene compared to how many genes increase intelligence more when there are two copies of it.
And how many genes increase size/intelligence with one copy but decrease it with two copies.