Bumble bees’ food preferences are jointly shaped by rapid evaluation of nectar sugar concentration and viscosity

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..., , , ## 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;
* ...