Meeting Abstract
Even during extreme fitness-defining behaviours like running away from predators, an animal should select a speed that balances the benefits of high speeds against the probability of mistakes. In my talk I will explore this theme by quantifying trade-offs between speed, maneuverability and motor control in two groups of animals; wild northern quolls (Dasyurus hallucatus) and Australian water dragons (Intellagama lesueurii). Across both animals with different locomotor styles, we found that the faster an individual approached a turn the higher the probability that they would crash and these risks were greater when negotiating tighter turns. To avoid crashes, animals modulated their running speed when they moved through turns of varying angles. Average speed for quolls when sprinting along a straight path was around 4.5 m/s but this decreased around tighter corners to speeds of around 1.5 m/s when running through 135 degree turns. I will also discuss how bipedal vs quadrupedal locomotion affects the turning ability of lizards that transition between these two locomotor forms. As the selection of an optimal movement speed must balance the relative cost and benefit of speed and maneuverability, it is also crucial that we have an understanding of how these two performance traits independently translate to fitness. During the third part of my talk, I will present data from a simple tablet-based game using human subjects, that provides a quantitative description for the relationship between speed and maneuverability with fitness. Taken together, our work reveals that animals must balance the competing demands of speed, maneuverability and control when selecting running speeds, and that the optimal choice will also depend on the relative importance of these performance traits with fitness.
