Methodological challenges in the study of primate cognition.

Laboratory studies of primate cognition face the problem that captive populations of a species are not always comparable, and generalizations to natural populations are never certain. Studies of primate cognition in the field face the problem that replications are expensive and difficult, and again different populations are not always comparable. To help remedy these problems, we recommend the creation of data banks where primary data and videotapes may be deposited (perhaps as a requirement of publication) to facilitate cross-examination, replication, and, eventually, the pooling of data across investigators.