Operative and Standard Operative Temperature: Tools for Thermal Energetics Studies

Abstract

Operative and standard operative temperatures, Te and Tes) are pseudo-temperatures denning “environmental temperature.” They have numerous applications, including extending the Scholander model ofthermoregulation to complex thermal environments. They may be calculated or measured directly using taxidermic mounts or models. Theory suggests that the distribution and structure of insulation, as well as the external size, shape and color ofthe animal, influence both Te and Tes. Experimental studies confirm this, and emphasize the effect of the regional distribution of insulation. Comparisons of various methods for determining Te and Tesindicate greatest accuracy for mounts. Uncertainties in calculations based on micrometeorology data make the use of mountsas a control essential. Rugged models, if carefully designed and exhaustively tested against mounts, might be used in place of mounts for some studies.