Benefits and costs of communication in groups
We often intuitively feel that more information is always better, and that organizations will work more efficiently if more information is shared, but this is often not true for a variety of reasons - as anyone working for a large organization should know. Information has surprising costs: not just producing it, but also opportunity costs of waiting for it, low signal-to-noise ratio if sharing is not selective, too-high uniformity across individuals, difficult/slow updating of information across the group, and other non-obvious consequences of information sharing that are negative for individuals and groups.
Bee Dance and maps
Honey bees (Apis) communicate the locations of food sources - but bumble bees do not. Why?
We demonstrated that benefits of communicating location are not actually common, and appear driven by rare, far away, but plentiful and diverse resources such as mass-flowering trees found in the tropics.
Dornhaus, A, Chittka, L 2004 ‘Why do honey bees dance?’, Behavioral Ecology and Sociobiology 55: 395-401 - pdf - field data in natural areas on increase in nectar collection with vs. without waggle dance location communication show benefit in tropics but not temperate areas
Dornhaus A, Klügl F, Oechslein C, Puppe F, Chittka L 2006 ‘Benefits of recruitment in honey bees: effects of ecology and colony size in an individual-based model’, Behavioral Ecology 17: 336-344 - pdf - simulation model shows strong dependence of waggle dance recruitment benefits on spatial distribution of resources
Dornhaus, A 2002 ‘Significance of honeybee recruitment strategies depending on foraging distance (Hymenoptera : Apidae : Apis mellifera)’, Entomologia Generalis 26: 93-100 - field data on artificial food sources show bees can find nearby food sources in response to recruitment even without waggle dance location information
Donaldson-Matasci MC, Dornhaus A 2012 ‘How habitat affects the benefits of communication in collectively foraging honey bees’, Behavioral Ecology and Sociobiology 66: 583-592 - pdf - field data on a variety of natural habitats show differences in dance benefits best explained by resource diversity
Raine, N E, Ings, T C, Dornhaus, A, Saleh, N, Chittka, L 2006 ‘Adaptation, genetic drift, pleiotropy, and history in the evolution of bee foraging behavior’, Advances in the Study of Behavior 36: 305-354 - pdf - review article on evolution of bee foraging behavior
Bee dance and time
We demonstrated that a variety of (opportunity) costs can arise just from the expectation of communication, and that speed and time delays can drive benefits. Contrary to some expecations, large bee colonies capitalize mostly on having a lot of scouts, not on having a lot of recruits.
Donaldson-Matasci MC, DeGrandi-Hoffman G, Dornhaus A 2013 ‘Bigger is better: honeybee colonies as distributed information-gathering systems’, Animal Behaviour 85: 585-592 - pdf - larger colonies benefit more from location communication not because they recruit more bees to the same food sources, but because they have more scouts to find food sources earlier
Dechaume-Moncharmont, F-X, Dornhaus, A, Houston, A I, McNamara, J M, Collins, E J, Franks, N R 2005 ‘The hidden cost of information in collective foraging’, Proceedings of the Royal Society: Biological Sciences 272: 1689-1695 - pdf - remaining in the nest to be available to be recruited is a cost of communication; longer availability of resource increases benefits of recruitment
Dornhaus A, Collins EJ, Dechaume-Moncharmont F-X, Houston A, Franks NR, McNamara J 2006 ‘Paying for information: partial loads in central place foragers’, Behavioral Ecology and Sociobiology 61: 151-161 - pdf - foragers may even benefit from returning prematurely from rewarding food sources in order to not miss important new information at the hive
Uniformity vs creativity
Generally communication is expected to reduce exploration and increase across-individual consistency, but we find that this depends on the details of behavioral rules.
Donaldson-Matasci M, Dornhaus A 2014 ‘Dance Communication Affects Consistency, but Not Breadth, of Resource Use in Pollen-Foraging Honey Bees’, PLOS One 9: e107527 - analyzing pollen loads from honey bees shows that communicating did not reduce the diversity of pollen collected, but did increase consistency of what was collected across foragers
Lanan M, Dornhaus A, Jones EI, Waser A, Bronstein JL 2012 ‘The trail less traveled: individual decision-making and its effect on group behavior’, PLoS One 7: e47976 - a simulation model of ants foraging on pheromone trails demonstrates that symmetry breaking, and thus consistency of individual resource choices, depends on how non-linear the choice algorithm is, i.e. on details of how choice probability relates to pheromone concentration; larger colonies may have more or less consistent foragers than small colonies depending on these mechanistic details