Why Have L2 Educators/Researchers Largely Ignored the Importance of L1 Skills For L2 Aptitude and L2 Achievement?

Despite the longstanding recognition of substantial individual differences (IDs) in L2 attainment, SLA/L2 researchers have a history of focusing primarily on universal characteristics and processes of language development. Theoretical work has failed to note and explore the nature and role of the strong evidence for large and stable IDs in early L1 attainment in all components of language development. Extensive research has also shown that there are strong relationships among IDs in L1 achievement, L2 aptitude, and L2 achievement outcomes. More recent investigations have found that prediction from the Modern Language Aptitude Test (MLAT), the strongest single predictor of L2 achievement, may be due largely to MLAT’s assessment of L1 abilities, reinforcing the position that IDs in L2 achievement are strongly related to and constrained by L1 achievement. Despite the evidence that students’ L2 achievement is closely related to their L1 achievement developed prior to L2 exposure, SLA/L2 researchers have largely failed to consider L1 skills as a factor that explains IDs in L2 achievement. Several hypotheses are proposed to explain why SLA/L2 researchers consider IDs in L1 attainment to be unimportant for L2 achievement.