Ge J, Shalem YM-B, Ge Z, Liu J, Wang X, Bloch G.
Integration of information from multiple sources drives and maintains the division of labour in bumble bee colonies. Current Opinion in Insect Science [Internet]. 2023 :101115.
Publisher's VersionAbstractBumble bees are eusocial bees in which the division of labor in reproduction and in task performance changes during their annual life cycle. The queen monopolizes reproduction in young colonies, but at later stages some workers start to challenge the queen and lay their own unfertilized eggs. The division of colony maintenance and growth tasks relates to worker body size. Reproduction and task performance are regulated by multiple social signals of the queen, the workers, and the brood. Here we review recent studies suggesting that bumble bees use multiple sources of information to establish and maintain division of labor in both reproduction and in task performance. Juvenile hormone is an important neuroendocrine signal involved in the regulation of division of labor in reproduction but not in worker task performance. The reliance on multiple signals facilitate flexibility in face of changes in the social and geophysical environment. Data Availability No data were used for the research described in the article.
Goldberg TS, Bloch G.
Inhibitory signaling in collective social insect networks, is it indeed uncommon?. Current Opinion in Insect Science [Internet]. 2023 :101107.
Publisher's VersionAbstractIndividual entities across levels of biological organization interact to reach collective decisions. In centralized neuronal networks, competing neural populations commonly accumulate information over time while increasing their own activity, and cross-inhibiting other populations until one group passes a given threshold. In social insects, there is good evidence for decisions mediated by positive feedbacks, but we found evidence for similar inhibitory signals only in honey bee (Apis mellifera) stop signals, and Pharaoh’s ant (Monomorium pharaonic) repellent pheromones, with only the former occasionally being used as cross-inhibition. We discuss whether these differences stem from insufficient research effort or represent genuine differences across levels of biological organization.
Gonulkirmaz-Cancalar O, Shertzer O, Bloch G.
Bumble Bees (Bombus terrestris) Use Time-Memory to Associate Reward with Color and Time of Day. Insects [Internet]. 2023;14 (8).
Publisher's VersionAbstractCircadian clocks regulate ecologically important complex behaviors in honey bees, but it is not clear whether similar capacities exist in other species of bees. One key behavior influenced by circadian clocks is time-memory, which enables foraging bees to precisely time flower visitation to periods of maximal pollen or nectar availability and reduces the costs of visiting a non-rewarding flower patch. Bumble bees live in smaller societies and typically forage over shorter distances than honey bees, and it is therefore not clear whether they can similarly associate reward with time of day. We trained individually marked bumble bee (Bombus terrestris) workers to forage for sugar syrup in a flight cage with yellow or blue feeders rewarding either during the morning or evening. After training for over two weeks, we recorded all visitations to colored feeders filled with only water. We performed two experiments, each with a different colony. We found that bees tended to show higher foraging activity during the morning and evening training sessions compared to other times during the day. During the test day, the trained bees were more likely to visit the rewarding rather than the non-rewarding colored feeders at the same time of day during the test sessions, indicating that they associated time of day and color with the sugar syrup reward. These observations lend credence to the hypothesis that bumble bees have efficient time-memory, indicating that this complex behavior is not limited to honey bees that evolved sophisticated social foraging behaviors over large distances.