Our conscious visual experience of the environment is derived from optical information consisting of an ever-changing distribution of light specified in angular units. To transform these units into linear spatial units appropriate for the specification of spatial extents, the visual system needs geometry and a ruler to scale the information. We review the evidence that perceptual rulers derive from the body’s phenotype, which is comprised of our morphology, physiology, and behavioral repertoire. We then propose that perception is also scaled relative to the socio-ecological environment. In this account, social resources affect perception by extending or contracting the relevant physiological ruler. Additionally, we suggest the human ecology functions to select the relevant perceptual ruler. Finally, we highlight research on individual differences as a useful method to further investigate these issues. In moving forward, a complete account of visual perception must necessarily include the socio-ecological environment.