Kacelnik, Alex - Facts and Theories in Decision Making: Sturnus vulgaris vs. Benjamin Franklin - Understanding decision-making involves many disciplines, including Evolutionary Biology, Economics, Psychology and Quantitative Behavioral Analysis. In this tutorial I review recent experiments on choice between different combinations of amount and delay to food that used starlings as experimental animals. The results are contrasted with predictions from theoretical models originating in these disciplines (including those advocated by B. Franklin). I show that while some models are better at data fitting they can be weaker in other respects. My overall message is that the worth of theoretical models is not identical to their predictive performance (how well they fit the data): Theories and models are validated by the accuracy of their predictions but should be judged by many additional criteria, including their value to guide research, and to place observations within broader fields of knowledge.