Behavioral performance in adult honey bees is influenced by the temperature experienced during their pupal development

Abstract

To investigate the possible consequences of brood-temperature regulation in honey bee colonies on the quality of behavioral performance of adults, we placed honey bee pupae in incubators and allowed them to develop at temperatures held constant at 32 degrees C, 34.5 degrees C, and 36 degrees C. This temperature range occurs naturally within hives. On emergence, the young adult bees were marked and introduced into foster colonies housed in normal and observation hives and allowed to live out their lives. No obvious difference in within-hive behavior was noted between the temperature-treated bees and the foster-colony bees. However, when the temperature-treated bees became foragers and were trained to visit a feeder 200 m from the hive, they exhibited clear differences in dance performance that could be correlated with the temperatures at which they had been raised: bees raised at 32 degrees C completed only approximately 20% of the dance circuits when compared with bees of the higher-temperature group. Also, the variance in the duration of the waggle phase is larger in 32 degrees C-raised bees compared with 36 degrees C-raised bees. All other parameters compared across all groups were not significantly different. One-trial learning and memory consolidation in the bees raised at different temperatures was investigated 1 and 10 min after conditioning the proboscis-extension reflex. Bees raised at 36 degrees C performed as expected for bees typically classified as "good learners," whereas bees raised at 32 degrees C and 34.5 degrees C performed significantly less well. We propose that the temperature at which pupae are raised will influence their behavioral performance as adults and may determine the tasks they carry out best inside and outside the hive.

Fig. 1.

(A) Probability (mean ± SD) that bees would dance after a visit to the feeder. Column a, probability for bees raised naturally in a standard hive (25 visits from five foragers); column b, probability for bees that were treated as pupae at 36°C (25 visits from five foragers); column c, those treated at 32°C (20 visits from four foragers). There is no significant difference among the three groups. (B) Number of dance circuits (mean ± SD) performed by the bees after each visit to the feeder. Columns represent the same three groups as described in A. Column a, 23 dances from five foragers; b, 22 dances from five foragers; c, 11 dances from four foragers. There is a significant difference between the bees raised at 32°C (c) and those raised at 36°C (b). (C) Duration of the waggle phase (mean ± SD, ms) in the dances performed by the bees. Columns represent the same three groups as described in A. Column a, 1,127 dance circuits from five foragers; b, 1,224 dance circuits from five foragers; c, 176 dance circuits from four foragers.

Fig. 2.

Proboscis-extension reflex response 1 or 10 min after one-trial odor conditioning in bees, the pupae of which were reared at 32°C, 34.5°C, and 36°C. Columns represent the percentage of responders after 1 min (55 bees raised at 32°C, 43 raised at 34.5°C, and 40 raised at 36°C) or 10 min (58 bees raised at 32°C, 54 raised at 34.5°C, and 23 raised at 36°C).