TY - JOUR
T1 - Learning and memory in workers reared by nutritionally stressed honey bee (Apis mellifera L.) colonies
AU - Mattila, Heather R.
AU - Smith, Brian H.
N1 - Funding Information:
We would like to thank the staff and students who were part of the Rothenbuhler Honey Bee Laboratory (OSU) when the study was conducted; we especially appreciated technical advice from S. Cobey and S. Kottcamp. HRM is also grateful to the members of the Department of Environmental Biology at the University of Guelph, her home institution when she visited OSU. This manuscript benefited from critical readings by D. Gibo, G. Otis, J. Schmidt, and G. Umphrey. Funding for HRM's travel to Ohio was provided by a Graduate Research Travel Grant from the Entomological Society of Canada. The research was supported by a Canada Graduate Scholarship and a Postdoctoral Fellowship from the Natural Sciences and Engineering Research Council of Canada (HRM) and a grant from National Institutes of Health National Center for Research Resources (grant no. RR014166 to BHS).
PY - 2008/12/15
Y1 - 2008/12/15
N2 - Chronic nutritional stress can have a negative impact on an individual's learning ability and memory. However, in social animals that share food among group members, such as the honey bee (Apis mellifera L.), it is unknown whether group-level nutritional stress is manifested in the learning performance of individuals. Accordingly, we examined learning and memory in honey bee workers reared by colonies exposed to varying degrees of long-term pollen stress. Pollen provides honey bee workers with almost all of the proteins, lipids, vitamins, and minerals that they require as larvae and adults. Colonies were created that were either chronically pollen poor or pollen rich, or were intermediate in pollen supply; treatments altered colonies' pollen stores and brood-rearing capacity. Workers from these colonies were put through a series of olfactory-conditioning assays using proboscis-extension response (PER). PER thresholds were determined, then workers learned in olfactory-conditioning trials to associate two floral odors (one novel and the other presented previously without reward) with stimulation with sucrose and a sucrose reward. The strength of the memory that was formed for the odor/sucrose association was tested after olfactory-conditioning assays ended. Colony-level nutritional status had no effect on worker learning or memory (response threshold of workers to sucrose, acquisition of the odor/sucrose association, occurrence of latent inhibition, or memory retention over 72 h). We conclude that potential effects of chronic, colony-wide nutrient deprivation on learning and memory are not found in workers, probably because colonies use brood-rearing capacity to buffer nutrient stress at the level of the individual.
AB - Chronic nutritional stress can have a negative impact on an individual's learning ability and memory. However, in social animals that share food among group members, such as the honey bee (Apis mellifera L.), it is unknown whether group-level nutritional stress is manifested in the learning performance of individuals. Accordingly, we examined learning and memory in honey bee workers reared by colonies exposed to varying degrees of long-term pollen stress. Pollen provides honey bee workers with almost all of the proteins, lipids, vitamins, and minerals that they require as larvae and adults. Colonies were created that were either chronically pollen poor or pollen rich, or were intermediate in pollen supply; treatments altered colonies' pollen stores and brood-rearing capacity. Workers from these colonies were put through a series of olfactory-conditioning assays using proboscis-extension response (PER). PER thresholds were determined, then workers learned in olfactory-conditioning trials to associate two floral odors (one novel and the other presented previously without reward) with stimulation with sucrose and a sucrose reward. The strength of the memory that was formed for the odor/sucrose association was tested after olfactory-conditioning assays ended. Colony-level nutritional status had no effect on worker learning or memory (response threshold of workers to sucrose, acquisition of the odor/sucrose association, occurrence of latent inhibition, or memory retention over 72 h). We conclude that potential effects of chronic, colony-wide nutrient deprivation on learning and memory are not found in workers, probably because colonies use brood-rearing capacity to buffer nutrient stress at the level of the individual.
KW - Behavioral assays
KW - Conditioned learning
KW - Honey bee workers
KW - Latent inhibition
KW - Memory
KW - Nutritional stress
KW - PER reflex
KW - Pollen diet
KW - Sucrose-response thresholds
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U2 - 10.1016/j.physbeh.2008.08.003
DO - 10.1016/j.physbeh.2008.08.003
M3 - Article
C2 - 18761030
AN - SCOPUS:56249137526
SN - 0031-9384
VL - 95
SP - 609
EP - 616
JO - Physiology and Behavior
JF - Physiology and Behavior
IS - 5
ER -