Innateness of magnitude perception? Skill can be acquired and mastered at all ages.

We agree with Leibovich et al.'s argument that the number sense theory should be re-evaluated. However, we argue that highly efficient skills (i.e., fluent and highly accurate, "automatic," performance) can be acquired and mastered at all ages. Hence, evidence for primacy or fluency in perceiving continuous magnitudes is insufficient for supporting strong conclusions about the innateness of this aptitude.