In 1935 the editor of this journal called attention to limitations inherent in the presentation of grouped or average data (Dunlap, 1935/1982). Because of contemporary misconceptions analogous to those Dunlap discussed, we clarify and emphasize the important distinction between the use of grouped data to demonstrate learning in a species and the reliable measurement of learning in identified individuals, as well as how best to assess the outcome of selective breeding with conditioning as the phenotype.