Ever since Adam and Eve days, Lactase is known to have been around. (Phelan, 2012) Back then, children would produce lactase to a certain point of their lives and then stop. This allowed for the breast feeding from the mother to occur, but it did not allow for the children to be able to consume lactose from that point on after they stopped producing lactase. Around 10,000 BC in Turkey, a mutation occurred that allowed for the lactase to keep producing, making people tolerant to the lactose. Mark Thomas of University College London is credited with figuring this occurring to have happened at this time period and place. As evolution occurred, this allowed for this mutation to spread across the whole entire world. Even though this mutation has occurred though, it is still said to be that two out of three adults are known to be lactose intolerant in today's era, but there has been lactase supplements that have been helpful to many people who are intolerant. The way that this was discovered was people who were able to digest the milk(lactose) were able to live to be able to reproduce, which also caused them to have healthier children while the people who could now digest the milk had children that were more likely to obtain a disease.