Spontaneous quantity discrimination of artificial flowers by foraging honeybees

Abstract

Many animals need to process numerical and quantity information in order to survive. Spontaneous quantity discrimination allows differentiation between two or more quantities without reinforcement or prior training on any numerical task. It is useful for assessing food resources, aggressive interactions, predator avoidance and prey choice. Honeybees have previously demonstrated landmark counting, quantity matching, use of numerical rules, quantity discrimination and arithmetic, but have not been tested for spontaneous quantity discrimination. In bees, spontaneous quantity discrimination could be useful when assessing the quantity of flowers available in a patch and thus maximizing foraging efficiency. In the current study, we assessed the spontaneous quantity discrimination behaviour of honeybees. Bees were trained to associate a single yellow artificial flower with sucrose. Bees were then tested for their ability to discriminate between 13 different quantity comparisons of artificial flowers (numeric ratio range: 0.08-0.8). Bees significantly preferred the higher quantity only in comparisons where '1' was the lower quantity and where there was a sufficient magnitudinal distance between quantities (e.g. 1 versus 12, 1 versus 4, and 1 versus 3 but not 1 versus 2). Our results suggest a possible evolutionary benefit to choosing a foraging patch with a higher quantity of flowers when resources are scarce.

Estimating on the fly: The approximate number system in rufous hummingbirds (Selasphorus rufus)

“…That our hummingbirds provided evidence of their numerical discrimination much more strongly in Experiment 2 is consistent with data from bees: in both cases, when the animals were trained that one of the options contained the reward and the other did not (Howard et al, 2019), both bees and our hummingbirds showed that they were capable of numerical discrimination that is not seen when the training was much less, and importantly, involved only a rewarding option (Howard et al, 2020). Indeed, substantial differences in the numerical abilities of animals are found depending on whether spontaneous numerical abilities are tested or if animals are first trained to associate a reward with a higher or lower numerosity (Agrillo & Bisazza, 2014).…”

Quantitative abilities of invertebrates: a methodological review

“…During foraging visits, bees can spontaneously discriminate among patches of flowers to maximize their foraging efficiency. Howard et al ( 2020a ) tested forager bees for their spontaneous preference by presenting 13 different quantity discriminations. Stimuli were artificial flowers (i.e., yellow circle) that differed for the number of items and overall surface area.…”

Counting on Numbers—Numerical Abilities in Grey Bamboo Sharks and Ocellate River Stingrays

“…However, having a side preference can generally be considered a reliable replacement strategy, as it enables an animal to secure 50% of the rewards. The low number of individuals advancing to the transfer test stage may not only reflect individual learning variation but could also indicated that numerical discrimination abilities may not be as fundamental to these species as to others [ 7 , 13 ]. Information on the ecology and the natural behavior of C. griseum and P. motoro is scarce and whether there is a need to discriminate quantities for mating, foraging or other behaviors is not known [ 61 , 62 ].…”

“…The ability to discriminate quantities has shown to be a widespread cognitive skill in a variety of animals including mammals [ 1 ], insects [ 2 ], birds [ 3 ], fish [ 4 ], amphibians [ 5 ] and reptiles [ 6 ]. This is not surprising, as quantity discrimination is advantageous for many behaviours including foraging [ 7 , 8 ], mating [ 9 , 10 ] and predator avoidance [ 11 , 12 ]. There is an ongoing debate in the literature on how quantities are perceived and processed [ 13 ].…”