The turtle (individual 03) takes 6 breaths and 20 strides during a locomotor bout which lasts ~25 seconds. This clip shows three simultaneously recorded images: the top portion of the screen shows light video, the middle shows x-ray video and the bottom shows ventilatory airflow. In this lateral view, the animal is wearing a custom-built pneumotach mask (appears dark in x-ray and light in regular video) which is attached to a differential pressure transducer and calibrated for airflow rates and volumes. The light area in the middle of the animal is the air-filled lungs. A metal marker has been glued to the skin just superficial to the abdominal muscles (transverse and oblique abdominis) which can be seen to move during breathing. In the airflow trace, zero airflow (the flat line in the middle) indicates no breathing, exhalation occurs when the trace is above zero and inhalation occurs when the trace is below zero. For this bout of locomotion, mean speed is 0.091 meters/second; stride frequency is 0.8 strides/second; and stride length is 0.114 meters/stride.
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