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Literacy and numeracy are more heritable than intelligence in primary school
Yulia Kovas1, Ivan Voronin, Andrey Kaydalov
11Laboratory for Cognitive Investigations and Behavioural Genetics, Department of Psychology, Tomsk State University.
Psychological Science
|September 5, 2013
Summary
Literacy and numeracy skills are more heritable than general intelligence in early school years. This is because education reduces environmental differences, highlighting genetic influences on learning.
Area of Science:
- Behavioral Genetics
- Developmental Psychology
- Educational Psychology
Background:
- Literacy and numeracy are primary educational goals, while general cognitive ability (g, intelligence) is not explicitly taught.
- It is commonly assumed that skills directly targeted by education are less heritable than innate cognitive abilities.
Purpose of the Study:
- To investigate the heritability of literacy, numeracy, and general cognitive ability (g).
- To compare the relative heritability of these traits in a longitudinal twin study.
Main Methods:
- Analysis of 7,500 UK twin pairs assessed longitudinally at ages 7, 9, and 12.
- Direct comparison of heritability estimates for multiple measures of literacy, numeracy, and g.
Main Results:
- Literacy and numeracy showed significantly higher heritability than g at ages 7 and 9.
- This pattern reversed by age 12, with g becoming more heritable.
Conclusions:
- Universal early education may reduce environmental variance, making remaining individual differences more heritable for literacy and numeracy.
- Increasing heritability of g during development suggests gene-environment correlation as individuals shape their experiences.
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