Increasing body temperature induces T-wave inversion in pythons. (A) The graph shows a representative trace of temperature measured in the thorax of a python during the heating protocol. Electrode recordings were made in brief intervals (black arrowheads) in which the heating pads were disconnected to reduce noise. (B) A schematic drawing (left) of a python and its heart (right) showing the location of the body surface electrodes. (C) A six-lead ECG recorded at 25.8°C (blue) and 35.2°C (red) of python 3. Note the change in T-wave polarity in each lead. We observed change in T-wave polarity in five snakes. F, foot electrode; L, left electrode; LA, left atrium; R, right electrode; RA, right atrium; Ven, ventricle.