"parents who are intelligent and love reading, both: (1) have lots of books in the house, and (2) pass on genes for liking reading to their children."
The paper that article is based on looks at adolescent bookishness, but that bookishness can't develop if there aren't books around. Seems like a pretty clear cut example of the environment playing the pivotal role. Children are reading less now than they were twenty years ago, and that's clearly not down to different genes.
But we have copious twin studies that tell us that, no, the family environment doesn’t play “the pivotal role”, and that genes are far more influential. Besides, books are prevalent enough that, even if the family home contains none, a child will encounter them at school and elsewhere.
I'm not sure that that's what the study found (https://www.sciencedirect.com/science/article/pii/S0049089X18300607). A home library better predicted literacy than additional years of schooling. Coming across books elsewhere wasn't as effective as experiencing them in the home. Now you'll say that that's because intelligent people are more likely to have books & intelligent kids. But I'm not sure that's full borne out: cultures of book ownership vary widely between countries. Are ex-Soviet countries with a strong history and culture of book ownership just more intelligent than other countries? After all, Czechians and Estonians grew up with twice as many books on average than Koreans and Belgiums.
Besides, the study (as you link to) is utterly, utterly worthless unless it makes major and serious attempts to control for the effects of genes (since we *know* from twin studies that genes have a huge effect on differences in education outcomes) and the study simply doesn’t do that.
Interestingly, there was a later studied that levied the same criticism as you make here (https://ila.onlinelibrary.wiley.com/doi/full/10.1002/rrq.160). This paper takes into account heritability, and I think it essentially agrees with both of us: the number of books in the home likely reflects parental love of reading/education which is largely heritable, but the actual literacy rate really was influenced by how many books were around the children. This is common sense, as literacy is a skill which improves through repeat exposure to reading, even if you had the best genetic predisposition to reading you're not going to become a good reader unless you actually read books, and those children who read early and often are going to be better readers.
Twin studies repeatedly and reliably show that shared family environment has only a small effect on outcomes. Such studies are usually comparing families within the same country and within the same culture. In that situation, “books in home” is not the causal factor, instead it is a marker for parents who have genes for caring about books, education and learning (that they then pass on to their children). Sure, cultural factors *also* affect the prevalence of books in a home, but, really, the “books in home” is not what’s important here, it’s just a consequence of parents and culture.
this seems like a very, very good point.
"parents who are intelligent and love reading, both: (1) have lots of books in the house, and (2) pass on genes for liking reading to their children."
The paper that article is based on looks at adolescent bookishness, but that bookishness can't develop if there aren't books around. Seems like a pretty clear cut example of the environment playing the pivotal role. Children are reading less now than they were twenty years ago, and that's clearly not down to different genes.
But we have copious twin studies that tell us that, no, the family environment doesn’t play “the pivotal role”, and that genes are far more influential. Besides, books are prevalent enough that, even if the family home contains none, a child will encounter them at school and elsewhere.
I'm not sure that that's what the study found (https://www.sciencedirect.com/science/article/pii/S0049089X18300607). A home library better predicted literacy than additional years of schooling. Coming across books elsewhere wasn't as effective as experiencing them in the home. Now you'll say that that's because intelligent people are more likely to have books & intelligent kids. But I'm not sure that's full borne out: cultures of book ownership vary widely between countries. Are ex-Soviet countries with a strong history and culture of book ownership just more intelligent than other countries? After all, Czechians and Estonians grew up with twice as many books on average than Koreans and Belgiums.
Besides, the study (as you link to) is utterly, utterly worthless unless it makes major and serious attempts to control for the effects of genes (since we *know* from twin studies that genes have a huge effect on differences in education outcomes) and the study simply doesn’t do that.
Interestingly, there was a later studied that levied the same criticism as you make here (https://ila.onlinelibrary.wiley.com/doi/full/10.1002/rrq.160). This paper takes into account heritability, and I think it essentially agrees with both of us: the number of books in the home likely reflects parental love of reading/education which is largely heritable, but the actual literacy rate really was influenced by how many books were around the children. This is common sense, as literacy is a skill which improves through repeat exposure to reading, even if you had the best genetic predisposition to reading you're not going to become a good reader unless you actually read books, and those children who read early and often are going to be better readers.
Twin studies repeatedly and reliably show that shared family environment has only a small effect on outcomes. Such studies are usually comparing families within the same country and within the same culture. In that situation, “books in home” is not the causal factor, instead it is a marker for parents who have genes for caring about books, education and learning (that they then pass on to their children). Sure, cultural factors *also* affect the prevalence of books in a home, but, really, the “books in home” is not what’s important here, it’s just a consequence of parents and culture.