A new study from a team of scientists from University of New Mexico and University of Pretoria, South Africa, shows that small songbirds will pant to reduce body temperature when in desert climates. From The Journal of Experimental Biology:

Carefully trapping birds in the arid southern Kalahari Desert, Wolf, Maxine Whitfield and Ben Smit gently injected a minute thermometer into the abdomen of the each of the birds before measuring the animals’ body temperature, metabolic rate and water loss as the temperature increased gradually from 25°C to a sweltering 54°C. However, if the birds began to overheat, the team jumped in quickly, getting the animals’ temperature back to normal by holding them in front of a chilly air conditioner while wiping them with ethanol...

The birds were able to offload heat to the environment at a rate faster than they were producing it through metabolism... the birds lose heat by evaporation to maintain a body temperature that is lower than the air temperature.

Source: Knight, Kathryn (2015). Hot birds pant to keep cooler than air. The Journal of Experimental Biology, 1615-1617.

Photo of Cactus Wren by Henry T. McLin