What is the minimum viable human brain? If our brains are indeed highly-redundant scale-free networks, would it be possible to eliminate a precisely targeted 99% of neurons without significant degradation? Can we simulate 1% of a brain on today's supercomputers? How about emulating an existing brain? Do animals have the raw hardware to match or exceed human intelligence? Can we download human 'software' into modified animals instead of machines? Are we already being simulated?
This would keep me up at night too.