The Etiology of Individual Differences in Second Language Acquisition in Australian School Students: A Behavior-Genetic Study

• We present one of the first behavior-genetic studies of individual differences in school students levels of achievement in instructed second language acquisition (ISLA). We assessed these language abilities in Australian twin pairs (maximum N pairs = 251) by means of teacher ratings, class rankings, and self-ratings of proficiency, and used the classic twin design to estimate the relative influences of genes, shared (family/school) environment, and unique environment. Achievement in ISLA was more influenced by additive genetic effects (72%, 68%, and 38% for teacher ratings, class rankings, and twin self-ratings, respectively) than by shared environment effects, which were generally not substantial (20%, 07%, and 13%). Genetic effects distinct to speaking and listening, on the one hand, and reading and writing, on the other, were evident for the twin self-ratings. We discuss the limitations and implications of these findings and point to research questions that could profitably be addressed in future studies.

Keyword

twin

behavior genetics

second language acquisition

reading

writing

speaking

listening

MEDICINE

MEDICIN

Publication and Content Type

ref (subject category)

art (subject category)