One popular story tells how Tepuhi, a spirit with the physical form of a sea-serpent, lifted the heavens to their present positions.  Finding that the earth was one massive stretch of land, he then smashed it up and formed oceans and rivers between the pieces.  Tepuhi as the woman, and earth as the man, later begot the human race. 

Another version tells of a substance called Te Atua o Heka which lay between earth and the heavens.  As it was slippery Te Atua o Heka moved about and caused earth and heavens to shift.  After some time it expanded and gradually forced them apart.  The human race was also formed from this substance.  The first product of it were spirits, both good and bad, who possessed supernatural powers.  Over time, however, they lost these powers and eventually became human. Te Atua o Heka, meanwhile had become personified as ruler of the heavens and earth and had gone to live in the sky.

Eventually a system of clans evolved and within these clans, life revolved around the family.  Traditionally, families consisted of three or four generations, all living and working together.  These extended families were headed by the most senior elder, who would represent the family in clan meetings.  The actual management of each family, however, was entrusted to his sons (or, if need to be, his daughters).  The sons in turn would look upon the eldest among them as leader but any dispute among them would be settled by the head of the family. When the head of the family died his position was taken over the his second eldest brother, or his eldest son, not by his widow.

The island, in turn, was ruled by the representatives from each clan, who sat in the council of chiefs with the king.  The king did not normally talk during these meetings, but expressed himself through the representatives of the Magatai clan, who also conducted the meetings.  Decisions were based on consensus.

Besides the clans, two large social groups called Tonga (south) and Tokelau (north) have been formed on the island.  Tonga and Tokelau do not have any significant positions in community affairs and are called together mainly when a large number of people is needed for a game.  People are more loyal to their clans than to either of these groups.

Despite the importance of clan loyalties and the many profound changes that have occurred in their way of life the people of Nanumaga still retain their traditional respect for their leaders. This is not always to their advantage, as was strikingly shown in recent times by their enthusiastic acceptance of an ill-conceived investment scheme, which brought heavy and embarrassing losses to the island. In 1979 a salesman from a United States land-selling company, Green Valley Acres Incorporated, arrived in Tuvalu. He was Mr Bula Tikotasi O'Brien, a part-Tuvaluan. About the same time the government was investing money with another American land developer, Mr Sydney Gross. O'Brien had come to sell the islanders pieces of land in Texas, and the people of Nanumaga, urged by their elders, yielded to his persuasion. As a result they committed nearly all the funds of the island to paying inflated prices for land which is likely never to be of any use to them because it is of very poor quality, isolated and without water or other essential services. Moreover, Tuvalu people have no right of access to U.S.A. It was an expensive way to learn how important it is to be careful when conducting business but the lesson is not likely to be forgotten.