Meeting Abstract
The ability to successfully evade predators is critical to any animal’s survival. To predict how well individuals can do this, ecologists primarily measure their maximum sprint speed. But what should a prey animal do when the predator is faster? In this situation, attempting to outrun the predator is pointless – instead, prey animals often exploit the biomechanical trade-off between speed and agility, and try to outmanoeuvre the predator. We constructed an optimality model that predicts the probability of a prey animal with particular speed and agility capabilities evading a predator along escape paths of differing curviness. In order to model a realistic trade-off, we used a function to link maximum sprint speed and agility to a morphological characteristic, limb length; maximum sprint speed increased with limb length, but agility decreased. We ran 400,000 simulations, modelling animals with 40 different limb lengths over 10,000 different escape paths of equal length. We found that animals typically took longer to complete the curvier escape paths, but this effect was negligible in the shortest legged individuals, which were consistently slow. However, animals with shorter legs were significantly faster than longer limbed individuals on curvier escape paths. This suggests that agile prey would be more likely to escape a faster predator if they chose a tortuous escape path. Our simple model provides a basis for more complex models and simulations. We aim to use these models to help answer questions about the escape capabilities of native species against introduced predators, and the influence of habitat.
