The neolithic period began 40,000 years ago. This was the period when hunter gatherers gave way to farmers. Don't you watch Neil Oliver?
It's amazing how some of the posts on this subject echo the blinkered fundamentalist opinions of the religious types who comment on God, Allah etc. It isn't for me to change the opinions of others but if you ask a stupid question I have to question your stupitity. So space aliens popped along to Earth every few hundred years and either built pyramids or drew big shapes in the desert? No other explanation? What research is this based on? Did you actually bother looking it up on the internet or did you have a stoner debate with someone who said it was true - because they looked it up on the internet? Are you just living in hope that the same space aliens are going to come back soon to abduct you and give you an anal probe? People built the pyramids using the knowledge, tools and resources available to them at the time. You can make a sextant to calculate angles out of two sticks and a length of string, that's all that would have been needed to work out the size and shape of a pyramid. At the same time as the pyramids in Egypt (give or take a couple of hundred years either way) we were putting up Stonehenge. Was that space aliens? If you are blissfull in your ignorance then fair play. Just so as you know that if you were around 3000 years ago chances are you'd be the dribbling idiot staring at the sun going "ooohh, hot!" and believing any sh*t that the shaman told you.
Those long queues of idiots waiting to audition for these so-called entertainment experts with all their bling, it isn't that far away from the slaves breaking the backs for the Pharaohs back then is it?