Heart Rate-Temperature Relationship in a Japanese Rat Snake

From February to October, 1981, the heart rate of a Japanese rat snake , Elaphe climacophora, was measured with a clinic electrocardiograph. The ECG electrodes were made of fishhooks and attached subcutaneously. After attachment of leads the snake was put in a box covered with a black curtain and placed in a room without airconditioning . The body temperature was monitored with a thermistor thermometer, and ranged from 0 C in February to 33.5 C in July. Based on 22 data derived from 274 records , the smoothed curve follows the equation of T=-7.263+10.873 ln H (r=0.983) where T equals temperature and H equals heart beats per minute. The logarithmic regression was also proved in some other snakes for the heart rate-temperature relationship .