Time’s crooked arrow: optimal foraging and rate-biased time perception

Time perception is critical to animal behaviours requiring anticipation of future events based on present information about the environment. Most models of animal foraging assume that animals are capable of measuring absolute time despite evidence that animals measure time with predictable biases in mean and variance. We incorporate the evidence for a rate-biased subjective time perception into a classic model of optimal foraging, the marginal value theorem. If acceleration of the clock rate is proportional to food intake rate and time is perceived similarly when in transit between patches as it is while waiting in a patch following eating, organisms are predicted to follow the predictions of the marginal value theorem exactly. However, a nonlinear relationship between clock rate and food intake rate, unequal wait and transit time perception, or any lag in the clock predicts characteristic suboptimal behaviour. We discuss how this mechanism for suboptimal behaviour compares with others in the literature and how it can be recognized in experiments.