SCALES, J.A.*; BUTLER, M.A.; Univ. of Tennessee; Univ. of Tennessee: Force Production During Acceleration in Gravid Iguanas

Many animals carry high reproductive loads, yet must maintain locomotor performance despite this burden. One aspect of locomotor performance that is considered important to fitness is acceleration. Green iguanas (Iguana iguana) are burst locomotors, carry a high reproductive load, and still are able to match the acceleration of �normal� iguanas. How do they do this? We compare the force production of individual hind and fore limbs during acceleration in gravid, early post-gravid and recovered green iguanas. Iguanas were induced to run down a 6 m trackway, and video and force measurements were recorded from individual footfalls as iguanas accelerated over a force plate. These data will be used to test whether iguanas are generating more braking forces when gravid, whether force production can be matched to mass gain during gestation, or iguanas may be generating force more economically by adjusting limb posture to align with ground forces.