How is it possible for insects to survive after they've had their head removed?
Short answer - the insect brain doesn't control body functions the way it does in mammals, for instance. Insects don't have an autonomic nervous system. Breathing in insects is passive - they have spiracles (holes) in the exoskeleton to allow air exchange for the body tissues.
Humans- heartbeat and breathing are under control of the brain. Remove the brain and breathing and heartbeat go away. Periplaneta spp. (cockroaches) can live for days without a head.
My understanding was that heart muscle, being myogenic, is not controlled by the brain and heart rate can keep at a steady pace -- even outside the body (if provided with oxygen etc.) . I hope I didn't misunderstand since this is one of my favorite useless-facts to bring up when a conversation goes awkward and silent and there's nothing to talk about
Read about the parasympathetic effects on the heart of the vagus nerve:
Most things in Biology are not absolute statements- it is possible to keep heart tissues alive and well outside the body.
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