Aging Capriciously

Once upon a time, there was a group of creatures called humans.  They evolve and live out their lives on a place they call Earth.   Earth is basically a spheroidal rock that revolves around a Class 3 star (called a sun) in a galaxy named the Milky Way.  No humans know where they came from, how they developed or why.  This is a subject of endless debate and speculation that has led to a plethora of social organizations which humans call religions.

Humans have a limited capacity to think and a very short life span, given the eons that the universe has existed.  Most humans live less than 100 earth years.  A year is the length of time it takes the Earth to revolve around the sun.  Humans seem to have two major characteristics that are shared throughout all members, clans and tribes of the species.  The first is called