Meeting Abstract

P2-153    Examining temperature dependence of burst performance: Is faster always better? Goodman, CM*; King, RL; Deban, SM; University of South Florida, Tampa FL; University of South Florida, Tampa FL; University of South Florida, Tampa FL colingoodman@usf.edu https://sites.google.com/view/debanlab

Many animal species rely on speed to seize prey or evade predation, and this reliance can generate strong selection for traits that confer a performance advantage. However, the mechanisms that facilitate greater burst performance are often strongly temperature dependent, suggesting the potential for an interaction between maximal performance and thermal sensitivity. To test this, we examined the temperature dependence of locomotor performance in three iguanian lizard species: the northern curly-tailed lizard (Leiocephalus carinatus), the Peter’s rock agama (Agama picticauda), and the black spiny-tailed iguana (Ctenosaura similis). Individuals from each species were collected from across their respective invaded ranges in Florida. We used high-speed imaging (500 Hz) to capture lizard sprinting performance at three temperatures (17, 25, 35 °C). We used coordinate data from digitized videos to extract maximum velocity, acceleration, and power. C. similis reached higher peak velocity (17 °C: 1.56 m s^-1; 25 °C: 2.21 m s^-1; 35 °C: 3.16 m s^-1 vs A. picticauda – 17 °C: 1.16 m s^-1; 25 °C: 1.86 m s^-1; 35 °C: 2.45 m s^-1 vs L. carinatus – 17 °C: 1.31 m s^-1; 25 °C: 1.55 m s^-1; 35 °C: 1.74 m s^-1) and power (17 °C: 13.49 W kg^-1; 25 °C: 26.57 W kg^-1; 35 °C: 62.33 W kg^-1 vs A. picticauda – 17 °C: 7.13 W kg^-1; 25 °C: 18.08 W kg^-1; 35 °C: 33.27 W kg^-1 vs L. carinatus – 17 °C: 9.90 W kg^-1; 25 °C: 24.07 W kg^-1; 35 °C: 36.14 W kg^-1) across all three temperatures, whereas L. carinatus exhibited greater acceleration at higher temperatures (25 °C: 29.21 m s^-2; 35 °C: 42.86 m s^-2), but lower peak velocities than both C. similis and A. picticauda. However, L. carinatus also exhibited lower temperature dependence of velocity across all temperature intervals (Q₁₀ 17-25 °C: 1.24; Q₁₀ 25-35 °C: 1.13), suggesting elevated burst performance may be less sustainable across temperatures.