Ergativity is a term used in traditional descriptive and typological linguistics to refer to a system of nominal case-marking where the subject of an intransitive verb has the same morphological marker as a direct object, and a different morphological marker from the subject of a transitive verb. Languages in which this system is found are divided into two main types, A and B (following Trask 1979:388). In Type A the ergative construction is used equally in all tenses and aspects. Furthermore, if there is verbal agreement, the verb agrees with the direct object in person and number in exactly the same way it agrees with the subject of an intransitive verb. The verb agrees with the transitive subject in a different way. Well-known representatives of this type are Basque, Australian ergative languages, certain North American languages, Tibeto-Burman and Chukchee. In type B there is most often a tense/aspect split, in which case the ergative construction is confined to the perfective aspect (or the past tense), and the nominative-accusative configuration is used elsewhere. Furthermore, if there is verbal agreement, the verb may agree with the direct object in number and gender but not in person.

There are various ways to construe the relationship between linguistic research and studies in language development. They can range in principle from strict dependence (one domain being parasitic on the other) to complete independence. Thus, it is now commonplace to find some developmental psycholinguists turning to generative linguistics for models through which to interpret child language (Chomsky 1969; Roeper 1973, 1982; Goodluck and Solan 1978, inter alia). This is not simply a matter of descriptive convenience. Research in grammatical theory and developmental psycholinguistics has grown increasingly interconnected since Chomsky first argued (1965:27) that hypothesized grammatical models within linguistics should be justified on the basis of their relation to a theory of language which specifies the innate abilities that make language acquisition possible. Hence the claim that linguistic theory is responsible for the “logical problem of language acquisition” (Baker 1979; Hornstein and Lightfoot 1981), i.e., gross properties of learning (relative rapidity, relative ease, overall lack of variability, general success, all on the basis of restricted input).

Perhaps the most pervasive issue in the study of adult second language (L2) acquisition concerns the relative contribution of prior first language (L1) experience — the contrastive component — and universal grammatical principles — the constructive component — to this language learning process. Concern with this issue stems in part from basic linguistic and psychological questions about the nature of language learning in the adult and in part from the desire to integrate these two components within a framework that can provide for a unified theory of language learning in general. Current research within the field endeavors to isolate and quantify each of these two components in the adult L2 learning process.

Within this context, this paper reports results of an experimental study of the acquisition of anaphora in structures such as in (1) and (2).

• (1) Alice helped Mary when she walked through the garden.

• (2) Alice helped Mary when walking through the garden.