DOI: 10.5061/dryad.g79cnp5tn
title: Bumble bees’ food preferences are jointly shaped by rapid evaluation of nectar sugar concentration and viscosity

description: Animals are often assumed to follow a strategy of energy maximization, and
 therefore should evaluate feeding options based on energy intake rates.
 However, at the proximal level, a direct estimate of
 energy intake rates, if that is possible at all, might require
 postabsorptive senses with relatively longer processing times, whereas an
 indirect estimate of energy intake through proxies like pre-absorptive
 senses of different sensory food properties might support rapid
 foraging decisions. Here, we show that nectar sugar concentration
 (sweetness) and nectar viscosity (resistance) drive preferences of bumble
 bees, Bombus terrestris, classical models for economic and
 foraging decision making. Using a tasteless/odourless biopolymer (Tylose),
 we created feeding options that differed in sweetness and resistance,
 properties that affect energy intake rate and can be immediately sensed.
 When energy intake rates were similar, bumble bees developed preferences
 based on sweetness and resistance. When energy intake rates were
 different, but sweetness and resistance were balanced against each other,
 bees developed no preferences. Decision dynamics during training indicated
 that bumble bees simultaneously evaluated sweetness and resistance to make
 decisions quickly (in seconds). These results suggest that bumble bees’
 food preferences are jointly affected by the immediate sensation of nectar
 sweetness and resistance as positively and negatively reinforcing
 properties, respectively, indicating a pre-absorptive proximate mechanism
 for rapid energy sensitive decisions in bumble bees.
description: ## Data and file structure The dataset contains all the raw data used for
 the statistical analyses and visualisation in the main text and the
 supplementary figures, from four experiments (experiment 1-4). In each
 experiment, foraging options with various nectar sugar concentrations
 and/or viscosities were provided. There are three spreadsheets in the
 dataset: 'Blocks of Landings', 'Test', 'Disrupted
 Drinking Behaviour'. ### In 'Blocks of Landings' there are
 six columns: * 'beeID' entries are the unique identification
 numbers for each individual bee used in each experiment; *
 'colony' entries are the identification numbers for each colony;
 * 'colour' entries are the counterbalanced colour sets used for
 different groups, with 1 = training with orange colour associated with the
 lower viscosity option, and lime colour associated with the higher
 viscosity option; 2 = vice versa; * 'block' entries are the
 numbers of the blocks that generate that values in the
 'percHC/V' column; * 'percHC/LV' values are the
 proportion of choices for the higher concentration option in experiment 1,
 3 and 4, or for the lower viscosity option in experiment 2. *
 'exp' entries are the experiment number; ### In 'Test'
 there are six columns: * 'beeID' entries are the unique
 identification numbers for each individual bee used in each experiment; *
 'colony' entries are the identification numbers for each colony;
 * 'colour' entries are the counterbalanced colour sets used for
 different groups, with 1 = training with orange colour associated with the
 lower viscosity option, and lime colour associated with the higher
 viscosity option; 2 = vice versa; * 'percHC/LV' values are the
 proportion of choices for the higher concentration option in experiment 1,
 3 and 4, or for the lower viscosity option in experiment 2; *
 'numland' values are the total number of landings in the test
 for each bee. * 'exp' entries are the experiment number; ### In
 'Disrupted Drinking Behaviour' there are eight columns: *
 'beeID' entries are the unique identification numbers for each
 individual bee used in each experiment; * 'block' entries are
 the numbers of the blocks that generate that values in the
 'percentage' column; * 'colony' entries are the
 identification numbers for each colony; * 'colour' entries are
 the counterbalanced colour sets used for different groups, with 1 =
 training with orange colour associated with the lower viscosity option,
 and lime colour associated with the higher viscosity option; 2 = vice
 versa; * 'group' entries record where the disrupted drinking
 behaviour happens, with 1 = disrupted drinking events on the higher
 viscosity option, and 2 = disrupted drinking events on the lower viscosity
 option; * 'percentage' values are the proportion of the
 disrupted drinking events in all the choices of one type of option within
 one block; * 'numep' values are the numbers of disrupted
 drinking events within one block; * 'exp' entries are the
 experiment number;