Beeban Kidron

Girls from poor families of the 'untouchable,' or lower, caste are 'married' to Yellamma as young as four. No longer allowed to marry a mortal, they are expected to bestow their entire lives to the service of the goddess.

If you think about evolution, sleep, at some time, was a dangerous undertaking. You lie down in your cave or shelter, and along comes a predator and has you for dinner. Many creatures do not sleep or sleep while standing so they can escape from dangerous situations.