According to the Population Reference Bureau, about 107 billion people have lived on Earth. (They calculated it using stats and guesses from when Homo sapiens first walked the earth, about 50,000 years ago, and assumed that 50,000 years ago there was a population of 2. I bet there was a humdinger of an argument about that statistic.) How many people have ever lived? Year Population Births / 1,000 Births since previous date Source: Population Reference Bureau estimates 50,000BC 2 - - 8,000BC 5,000,000 80 1,137,789,769 AD1 300,000,000 80 46,025,332,354 1200 450,000,000 60 26,591,343,000 1650 500,000,000 60 12,782,002,453 1750 ...