“…One of the several factors that might have contributed to this finding was the younger age of the subjects in Experiment 2 (90 days) relative to those in Experiment 1 (181-197 days) and those in Hobbs and Elkins (1976) (180 days). Although young adult rats generally acquire stronger taste aversions than rat pups (e.g., Baker, Baker, & Kesner, 1977;Caza, Steinert, & Spear, 1980), there is no clear evidence that aversion strength is enhanced by further maturation (Franchina & Horowitz, 1982;Guanowsky & Misanin, 1983). Nevertheless, we returned to the use of older subjects in the next experiment.…”