And that development is affected by nutrition deficiencies or sufficiencies, presence or absence of a vast array of toxins, the kinds of stressors that act on the organism both before and after birth, and the deficiencies or sufficiencies of nurturing and environmental stimulation.

You just have to look at that paper by Carpenter and Niven: “Environmental causes of violence” (Physiology & Behavior 99 (2010) 260–268) from back in 2010, where they document the relationship between lowered IQ and heightened levels of violence due to lead exposure: “…a number of environmental exposures are documented to result in a common pattern of neurobehavioral effects, including lowered IQ, shortened attention span, and increased frequency of antisocial behavior. This pattern is best described for children exposed to lead early in life, but a similar pattern is seen upon exposure to polychlorinated biphenyls and methyl mercury. Although not as extensively studied, similar decrements in IQ are seen upon exposure to arsenic and secondhand smoke (SHS) exposure. Prenatal and postnatal SHS exposure is also associated with increased rates of conduct disorder and attention deficit hyperactivity. Recent evidence suggests that temporal trends in rates of violent crime in many nations are consistent with earlier preschool blood lead trends, with a lag of about 20 years. These ecologic correlations are consistent with many controlled studies suggesting that lead- exposed children suffer irreversible brain alterations that make them more likely to commit violent crimes as young adults. If this pattern is true for lead and other contaminants, the most effective way to fight crime may be to prevent exposure to these contaminants….”

The idea that group variations in biology can influence group variations in behavior should be made a thoughtcrime. (Except, of course, where conseratives are concerned, where we know that their diminished anterior cingulate cortexes are to blame for their backward views.)

This is so interesting to me. I recently worked with two groups of middle school students that attempted to address apathy in school. One issue we had was the group feeling of apathy. This study would help me show that IQ and in turn teacher perception, impacts how students do in school. Students that have high IQs but low belief of school ability, may show low IQs and in turn apathy at school. Thanks for sharing this study. As an educator I am always looking for ways to increase engagement and understand why students do what they do.

Humans vary in strength. Within a sex, much of that strength is developmental and experiential.

However, chimpanzees and humans vary in strength by an ordre of magnitude greater than the variation among normal humans. This difference is not thought to be developmental.

Humans and walruses vary within species as to how accustom they are to cold. Within humans, comfort level at cold vs warm conditions is known to be experiential. You “set” your range between birth and about age 5.

Walrus can handle much much colder condition than humans. The difference between humans and walrus is not developmental. According to your logic, either human variation IS GENETIC DAMMIT or the human-walrus difference IS NOT GENTIC DAMMIT

Are you starting to get this?

I’m beginning to wonder if I’ve stumbled onto a blog of the Discovery Institute.

There are no pre-qualifications for commenting on this blog. But if and when you come back with your response, in your case, it needs to be respectful, somewhat apologetic, and you need to demonstrate that you’ve learned something or your comments won’t be appreciated.

To rate your poo-pooing dismissal, innaters have obviously misunderstood something pretty fundamental, so perhaps you can enlighten me about the position of anti-innaters on evolution.
You state:

..variation across humans in ability is not likely genetically determined..

Have you allowed yourself weasel-room in the words “variation ” and “determined”? Otherwise it looks like you negate any genetic component to ability.
Do the cognitive differences between us and chimpanzees have nothing to do with genetics?
Is intelligence not adaptive? If it is, how can evolution work on it if there are no genetically determined variations in it? If it isn’t, how did it evolve?

I’m beginning to wonder if I’ve stumbled onto a blog of the Discovery Institute.

Very often people have received the “knowledge” somewhere along the way that abilities really really and truly really innate, no kidding. Despite the fact that what we know about neurobiology contradicts this, it is the believe a lot of people come to the table with, and it is a strongly held belief.

This does not rule out innateness, it just requires that the assumption is that variation across humans in ability is not likely genetically determined (though it can be very “hard wired” if we allow for the term “hard wired” to mean things other than “your genes made it happen a certain way.”

So, when folks with the received knowledge that “it must be innate” run into evidence that it is not, it seems to be a common thing to see the sort of argument you make pop up.

I don’t like what I see so it is flaky. The waters are muddied. It is not objective. The science is soft.

Innatists are so predictable it actually is funny.