The effect of temperature on the rate of development and color patterns of two honey bee queen lines (black and yellow) was examined. The queens completed the postcapping period (last instar and pupal stages) in incubators maintained at temperatures corresponding with the natural range found in the brood nest: 30.5, 33.5, and 35.5∘C. The black line required significantly fewer accumulated degree-days for development than the yellow line at all temperatures. The queens from both lines had Significantly more yellow coloration on the integument when they completed the postcapping period at 35.5∘C than at 30.5∘C. These results suggest that brood nest temperatures playa more important role in the rate of development of queen lines and in the phenotypic expression of color patterns than has previously been recognized.