Figure 1.

Modest environmental enrichment.

(A) Full two-level cage view, (B) one-level of a two-level cage; Critter Nation, Muncie IN. Housing design may be manipulated in multiple ways. For example, adding/removing dividers between levels to control space allotment, changing objects/toys and their location, providing access to running wheels, in addition to varying the number of cage mates. Set-up will be dependent on the overall purpose of enrichment and the controlled factors of interest (i.e., novelty, physical activity, social interaction).