That is one interpretation. Another interpretation is that in pursuing academic career requires a certain attitude towards studying which people growing in a family of academics are a lot more likely to have. In STEM it makes a lot more sense financially to enter the workforce after graduation so staying in university for another 5+ years requires some real love for science. In my experience people with parents in academia are more likely to get financial and moral from their family while they are doing phd.
It is pretty well established that educational attainment is significantly heritable [1]. Although less studied, there is evidence of significant heritability of interests as well [2]
Twin studies, adoption studies, and now GWAS studies are quickly putting an end to the idea of some significant but elusive environmental effect that accounts for heritability measures in exclusion to genes. Regarding the articles, I don't find them compelling. The author of the first one identifies himself as an emergentist, which is conceptually vacuous. The critique in the second article doesn't target the strongest of heritability studies regarding IQ, educational attainment, etc, which have been widely replicated.
All behavioral genetic studies heretofore rely on statistical analysis to draw correlations from datasets. Even ones that identiy specific SNPs are often unable to identify the physiological mechanism by which, say, Gene X influences intelligence. Without that, it's impossible to conclude that expression of Gene X isn't environmentally-influenced, and only has positive effects on intelligence when a certain diet is consumed, or sleep schedule kept, or common childhood illness avoided, for example. Another trait influenced by complex genetic and environmental factors, variability in adult height, has similarly been held to be highly heritable based on flawed studies with flawed construction, methodology, and assumptions, despite the fact that the average in many countries has changed on a time scale incompatible with a purely or even highly genetic basis. And height is easy to measure: get a ruler. Models of intelligence have shifted over the years because, speaking frankly, we don't really know how to measure it objectively.
Your objection to the first is ad hominem, to the second erroneous.
Belief in genetic determinism, as we conceive it, is at odds with the principles of skepticism and scientific inquiry. Like eugenics before it, it really, really wants to find a scientific basis to justify the state of the world we live in even as that state shifts under us. There are massive holes in both the execution of studies and the underlying rationale, and it's impossible to speak in good faith on the topic without acknowledging that.
>Without that, it's impossible to conclude that expression of Gene X isn't environmentally-influenced
Conclusions do not require certainty. Science is about converging to the best explanation, not about unimpeachable conclusions. But when there are no plausible causal paths to explain measured correlations aside from, e.g., gene->phenotype causation, then causation along the available causal path is a valid tentative conclusion.
> variability in adult height, has similarly been held to be highly heritable... despite the fact that the average in many countries has changed on a time scale incompatible with a purely or even highly genetic basis.
I don't know how you can possibly think this supports your argument against genetic heritability. Height has a heritability measure of around 80%, which leaves 20% for environmental factors. There is no contradiction in noting that average height has increased over time when the current best analysis leaves significant room for variation due to environment.
>despite the fact that the average in many countries has changed on a time scale incompatible with a purely or even highly genetic basis.
Nothing you've said demonstrates this claim.
>Your objection to the first is ad hominem
Nope. Emergentism is his avowed conceptual framework, a lens through which he analyzes evidence and draws conclusions. But if the conceptual framework is vacuous, which it is, then that undermines the value of conclusions based on that framework.
If certainty has not been achieved, then you should remain skeptical. The lack of a causal explanation is a massive discontinuity in logic which suggests that our conclusions may be very wrong ("retrograde action" wrong).
>Height has a heritability measure of around 80%, which leaves 20% for environmental factors.
This is what I mean. The studies that determined this used datasets from wealthy Western countries that are more ethnically homogeneous than average. Similar studies done in less wealthy countries found measures of environmental influence as high as 40%. In countries of similar wealth, average height can be predicted by measuring the level of economic inequality, suggesting that environmental factors such as healthcare, nutrition, and fitness access are all significant inputs.
>Nothing you've said demonstrates this claim.
Dutch average height for men grew 8 inches in a century. For comparison, average height for men worldwide has grown around 3 inches in the last millennium. There is evidence to suggest that pre-agricultural male height was similar to where it is now, if not taller; the structure of our civilization is the difference between the average man being 5'6" and 6", i.e., more than one SD from today's average in either direction.
I understand that it is harrowing to think that even our basic physiological attributes may be determined in no small part by the way we're treated by society (that is to say, that decisions could be made to improve your quality of life but are not), but it is very much a possibility.
>Nope. Emergentism is his avowed conceptual framework, a lens through which he analyzes evidence and draws conclusions. But if the conceptual framework is vacuous, which it is, then that undermines the value of conclusions based on that framework.
You are literally invoking a textbook ad hominem fallacy.
>If certainty has not been achieved, then you should remain skeptical
This is like saying you should be skeptical of all scientific claims. But such a claim is in tension with the obvious successes of science and engineering despite the inherent tentativeness of scientific conclusions. Clearly we need something more nuanced. We can draw tentative conclusions and move forward with knowledge while also acknowledging the tentative nature of said knowledge. Global skepticism regarding all scientific results is paralyzing.
>The studies that determined this used datasets from wealthy Western countries that are more ethnically homogeneous than average.
It has to be for any such measure to be meaningful. For example, if you put a toddler in a box and starve it to death, its development stops completely. But this doesn't mean that environmental influence is 100% for all phenotypes. Heritability is a blunt measure for something highly multidimensional. As such, care must be used in its interpretation. What heritability tells us is that given similar environments, what variation in measurable traits is due to variation in genetics or variation in environment. An ideal measure of heritability is a function of environment and would be proportional to the rate of change of environmental influence at every step change in environment.
Of course, such a measure is impossible and so we're left with our current blunt measure. But we can reason about some features of the ideal measure. For example, environmental influences have diminishing returns, thus there comes a point at which the rate of change of environmental influence is zero, meaning better or worse environment has no bearing on the trait and genetic variation dominates outcomes. On the other extreme, environmental influences are dominant. The relevant questions for the validity of heritability is whether the rate of change of environmental influence is steep at the current average environment. If it is steep, then it invalidates drawing conclusions based on measured heritability as the value is unstable.
But your point about Dutch average height does not bear on this. The heritability measure is blind to global average changes in quality of environment. The fact that average height grew so substantially implies that the average environment changed substantially over that period. The Flynn effect is another example, where the average IQ across the population grew substantially over a similar time period. But this doesn't have any direct relevance to the heritability measure of IQ. The question is whether current measures of heritability are stable for typical variations in environment. Regarding height, I would guess yes as calories are abundant in the western world, even among the poor.
>You are literally invoking a textbook ad hominem fallacy.
Notice the word fallacy. Identifying logical fallacies by name is to help recognize patterns of invalid arguments. Ad hominem is only relevant if the argument is not valid. But my point a vacuous conceptual framework leading to specious conclusions is a valid argument.
