Is the acquisition of basic-colour terms in young children constrained?

We investigated whether the learning of colour terms in childhood is constrained by a developmental order of acquisition as predicted by Berlin and Kay [1969 Basic Color Terms (Berkeley, CA: University of California Press)]. Forty-three children, aged between 2 and 5 years and grouped according to language ability, were given two tasks testing colour conceptualisation. Colour comprehension was assessed in a spoken-word-to-colour-matching task in which a target colour was presented in conjunction with two distractor colours. Colour naming was measured in an explicit naming task in which colours were presented individually for oral naming. Results showed that children's knowledge of basic-colour terms varied across tasks and language age, providing little support for a systematic developmental order. In addition, we found only limited support for an advantage for the conceptualisation of primary (red, green, blue, yellow, black, white) compared to non-primary colour terms across tasks and language age. Instead, our data suggest that children acquire reliable knowledge of nine basic colours within a 3-month period (35.6 to 39.5 months) after which there is a considerable lag of up to 9 months before accurate knowledge of the final two colours (brown and grey) is acquired. We propose that children acquire colour term knowledge in two distinct time frames that reflect the establishment of, first, the exterior (yellow, blue, black, green, white, pink, orange, red, and purple) and, second, the interior structure (brown and grey) of conceptual colour space. These results fail to provide significant support for the order predicted by Berlin and Kay, and suggest, instead, that the development of colour term knowledge is largely unconstrained.