If the earth is 4+ billion years old, then why are we, as humans, so far behind on the technical curve? Since the advent of methods for keeping history, and judging from old books, we havn't made many advancments until around 2-3 thousands years ago. What happened for the billions of years beforehand? Did we just sit and stare at a rock? That doesn't make any sense... especially considering how from birth most of us want to learn and create... Keep this in perspective, 4 billion years of knowledge, verse how far we've come in only 2000 years... we should be well beyond UFO's by now.

Also, since we know humans looked like humans do today 2000 years ago, how come we never changed over 2000 years? Why don't I have 2 brains yet?

Will todays monkeys become humans in a few thousand years?

If we took a human and put them in the water their entire life, and their children, and so on, for lets say 1000 years, will they start to grow gills? Kinda like the Zora in Zelda.