AbstractThe heat and water balance of the antelope jack rabbit,Lepus alleni, was studied at various ambient temperatures. At high ambient temperature the animal primarily depends on evaporation for dissipation of the heat load. The use of water was, however, less than could be expected if only body size is considered.It was shown that, when the ambient temperature is below body temperature, there is a two‐ to three‐fold increase in the conductance of the animal as ambient approaches body temperature. This facilitates dry heat loss and contributes to water economy. At ambient temperatures above body temperature the direction of heat flow is reversed, now being from the environment to the body. In this situation the heat flow inwards is impeded by a decrease in conductance to minimal values, thus achieving a considerable saving in the use of water for evaporat
展开▼