we probably underestimate the complexity of the nervous system to a profound degree. just in terms of low-hanging fruit in that category, not most people know

we probably underestimate the complexity of the nervous system to a profound degree. just in terms of low-hanging fruit in that category, not most people know this, but the gut contains a "brain" on the level of a frog's brain, which is more reasonably understood as a specialized brain-like digestion processing management unit. similar to the way computers have CPUs and GPUs, humans have brains and stomach brains. there's evidence that female humans may also have a third "brain" which performs similar specialized processing for the uterus, but I don't remember if that was ever fully proven.