Vertebrate hearts all have an inbuilt pacemaker which sets the baseline for heart contractions. This can be influenced by chemical stimuli or nerve impulses or both to increase or decrease the rate of contractions. The heart will continue to contract while there is a supply of oxygen and energy (glucose).
Crocodile_dan, I do recall the Cane Toad heart dissections and ECGs. Pracs used to go for 3 hours but sometimes people stayed on to do further investigations for another hour or two. So long as you irrigated with Ringer’s Solution, the heart would continue to beat for hours. And croc hearts are amazing - four chambered like birds and mammals but with mechanisms for avoiding the lungs when submerged.
The muscular contractions that can occur sometime after death are short and limited from what I can recall, which is not much at all so if anyone can contribute, please feel free.
A couple of tales to keep in the spirit of things. When growing up, we used to raise our chooks fo the table. Dad would chop off their heads, tie the legs together with string and hang them on the back fence to bleed. You would occasionally have the chooks kick themselves free of their bonds and fall off the fence. The prize, however, goes to the chook that escaped Dad’s grasp once its head had been removed. This headless wonder did a full 2½ circuits of the backyard including around the clothes hoist, at full pace, before finally collapsing. That was the last time I watched while Dad despatched the chooks.
Dad was medic in the army and they had morgue set in Darwin to store the dead before they could be flown south. He got the shock of his life early on when he had just finished laying out a body, turned away for a moment, heard a noise and so turned back only to find this dead body sitting bolt upright. I have no doubt had it been me I would have been due for a change of underwear!
Blue
