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Abstract Reproductive division of labor in insect societies is regulated through multiple concurrent mechanisms, primarily chemical and behavioral. Here, we examined if the Dufour’s gland secretion in the primitively eusocial bumble beeBombus impatienssignals information about caste, social condition, and reproductive status. We chemically analyzed Dufour’s gland contents across castes, age groups, social and reproductive conditions, and examined worker behavioral and antennal responses to gland extracts. We found that workers and queens each possess caste-specific compounds in their Dufour’s glands. Queens and gynes differed from workers based on the presence of diterpene compounds which were absent in workers, whereas four esters were exclusive to workers. These esters, as well as the total amounts of hydrocarbons in the gland, provided a separation between castes and also between fertile and sterile workers. Olfactometer bioassays demonstrated attraction of workers to Dufour’s gland extracts that did not represent a reproductive conflict, while electroantennogram recordings showed higher overall antennal sensitivity in queenless workers. Our results demonstrate that compounds in the Dufour’s gland act as caste- and physiology-specific signals and are used by workers to discriminate between workers of different social and reproductive status.
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CULTURAL IDENTITIES AND RESOLUTION OF SOCIAL DILEMMAS
We report an experiment on payoff‐equivalent, sequential provision and appropriation games with high‐ and low‐caste Indian villagers. A central question is whether caste identities affect resolution of social dilemmas. Making caste salient elicits striking changes in behavior compared to baseline treatment with no information about others' castes. Homogenous groups with high caste villagers are more successful in resolving social dilemmas than homogenous groups with low caste villagers. The success of mixed‐caste groups is somewhere between, which is inconsistent with a group identity model. Absent salient information on caste, behavior is inconsistent with unconditional social preferences but as predicted by reciprocity. (JELC93, H41, Z13)
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- Award ID(s):
- 1658743
- PAR ID:
- 10078159
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Economic Inquiry
- Volume:
- 58
- Issue:
- 1
- ISSN:
- 0095-2583
- Page Range / eLocation ID:
- p. 49-66
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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