the body temperature of Arabian oryx fluctuates during the day from about 38oC, the normal body temperature, up to 42oC at midday, and then falls back to 38oC at night. Calculate how much water heterothermia saves over the 24 hr period. Normal Tb = 38oC. Max Tb = 42oC during middle part of day. You may need to know that the specific heat of tissue = 3.48 kJ (kg • oC), that is, it takes 3.47 kJ of heat to raise one kg of tissue one degree centigrade. We have already been introduced to the heat of vaporization of water which equals 2404.2 kJ/liter, i.e. it takes 2404.2 kJ of heat to convert a liter of water into vapor.