We examined thermoregulation and cutaneous evaporative cooling by heat-stressed desert columbids (diamond dove, flock bronzewing, rock pigeon, and spinifex pigeon), temperate-zone columbids (common and brush bronzewing, and crested pigeon), and rainforest columbids (wonga pigeon, Luzon bleeding heart, and emerald dove). Body temperature at a T-a of 47degreesC was lower for desert birds (43.3degreesC) than for temperate-zone birds (43.6degreesC) and rainforest birds (44.4degreesC). Body-skin temperature difference (DeltaT) was only 0.2degreesC for rainforest species; it was significantly higher at 0.4degreesC for temperate-zone pigeons, and significantly higher again at 0.9degreesC for arid-zone birds. Cutaneous water evaporation (CWE) was 2.1 mg H2O cm(-2) h(-1) for rainforest species; it was significantly higher at 5.6 mg H2O cm(-2) h(-1) or temperate-zone birds, and significantly higher again at 13.5 mg H2O cm(-2) h(-1) for arid-zone pigeons. CWE of young wonga and bleeding heart pigeons was similar to that of adults, but was very high for young birds of other species. Comparisons at 42degreesC were very similar. Cutaneous evaporative cooling (CEC), which was suggested to be an evolutionarily recent mechanism compared to panting, is not effective for the three arboreal rainforest pigeons and probably did not occur in ancestral columbids that were presumably arboreal. We suggest that effective CEC evolved in altricial hatchlings of pigeons in a temperate-zone climate as a cooling mechanism, and has achieved its highest effectiveness in both young and adult desert pigeons.