Agency is often mistaken for behaviour. In APS, however, biological agency does not require overt behaviour.
Agency refers to viability-oriented activity through which living systems contribute to maintaining or re-establishing conditions compatible with their continued organisation. Behaviour may sometimes form part of this activity, but many forms of biological agency occur without the kinds of observable action ordinarily described as behaviour.
Cells regulate metabolism, tissues coordinate repair, organisms maintain physiological conditions, and developmental systems respond to changing conditions without necessarily producing overt behaviour.
APS therefore distinguishes behaviour from agency. Behaviour describes a class of observable biological activity. Agency concerns the relationship between activity and the viability of the living organisation in which it occurs. Behaviour may provide evidence of agency where that relationship can be established, but behaviour alone does not demonstrate agency.
Conversely, the absence of overt behaviour does not demonstrate the absence of agency. Relevant viability-oriented activity may occur through physiological, cellular, developmental, regulatory, or other biological processes.
APS Principle: Behaviour may provide evidence of biological agency, but behaviour and agency are not equivalent. Agency concerns viability-oriented activity of living organisation and need not take the form of overt behaviour.