A relatively juvenile civilization inhabiting twelve villages on M7G-677. For more than five hundred years the Wraith have not come to cull this planet, partially due to the fact that the entire population engages in ritual self-sacrifices on the eve of their 25th birthdays.
Forced suicides have occurred in the past, though this is only out of necessity if the individual has pressing reservations. According to Keras, the villagers can be "persuasive" when the time comes. In their eyes 25 years plus one day does not necessarily mean the Wraith will sense an adult and come, but an approximate, yet consistent age had to be decided upon.
Unbeknownst to the population, self-sacrifices are only partially responsible for their survival. A Zero Point Module, concealed in an ancient abandoned city, powers an energy field which neutralizes all forms of electromagnetic energy (Including that which sustains Puddle Jumpers and Darts). Because there are adequate sources of food elsewhere, the Wraith do not bother culling the villagers on foot.
The suicides control the size of the population and prevent them from migrating beyond the field's perimeter, but the Z.P.M. is chiefly responsible. For centuries the villagers did not know that their suicides were only partly responsible. When Rodney McKay arrived with John Sheppard's unit, he was able to manually recalibrate the size of the field to accommodate an expanding population that would last for at least half a century before the module died. Only after this calibration did the suicides cease.
The people have successfully built a thriving metropolis in the treetops, with frequent exchanges of children between villages to maintain the diversity of their gene pools. Each child is trained in the use of bows and arrows, as well as crossbows and the construction of other man-made weapons.
Up until the suicide pacts ended religion played a prominent role. Only one who had given their own lives could be permitted to enter into the Eternal Rest. To die at the hands of the Wraith would prevent reaching this plane.
Childhood's End - Major Sheppard's unit visits M7G-677 and encounters a race of children who perform ritual suicides on the eve of turning 25 to prevent their slaughter by the Wraith.