 By the beginning of the Neolithic (c. 6,000 BP) sea levels in the Bristol Channel were still about lower than today.The historian John Davies theorised that the story of Cantre'r Gwaelod's drowning and tales in the Mabinogion, of the waters between Wales and Ireland being narrower and shallower, may be distant folk memories of this time.Neolithic colonists integrated with the indigenous people, gradually changing their lifestyles from a nomadic life of hunting and gathering, to become settled farmers about 6,000 BP – the Neolithic Revolution.