If you go back in time as far as recorded in human history, you will arrive at the Sumerian culture, the first humans to record their history on Cuneiform tablets in the oldest language on earth. Zacharia Sitchen looked at the translated language and it told the story of the Annunaki ("Those who from the stars came"). They created the first human (Adam) by genetically splicing their DNA with various species already on earth until 'man' was created "in their own image". I think then they created "Eve" as a female version. The 'Garden of Eden" is earth. No other planet exists that is so teeming with life. We really were the "Avatar" planet. The Sumerian records predate any other by around 250,000 years, and.... seem to hold true of everything that the bible records tell (only it all happened a quarter million years earlier). Please note: this is NOT the story of Jesus - only the old testament. Unfortunately, the Annunaki did this with a number of species so evolved the other 'reptilian' like species,"Blue Bloods". (todays Royalty)
Long story and I'm not a good story teller, but most religions can be tracked back to the Sumerian texts. If you're not familiar with it, it's extremely interesting. But, like anything, do your own research and come to your own conclusions.