Open-field activity in mice as a function of ceiling height: A genotype-environment interaction.

Three inbred strains of mice, C57BL/6, DAB/2, and BALB/c, were run in the standard McClearn-type open-field with l-, 1 5/8-, and 36-inch ceiling heights. Although all strains showed increased activity as a function of lowered ceiling height, an interaction between strain and ceiling height was obtained: while BALB/c mice were the least active strain in the 36-inch-ceiling-height field, they were the most active strain in the 1-inch condition. Implications of this strain times environment interaction for the well-established low open-field activity of BALB/c and other albino strains are discussed.