Hierarchy research

Hierarchy examples
1.Cubes - This image shows hierarchy by putting the different sized cubes in a certain order to create a wave of some sort
http://www.shutterstock.com/pic-92366806/stock-photo-colored-orderly-arrangement-of-cubes-in-three-dimensional-space.html

 2.Spheres - This shows hierarchy as the spheres are ordered in a way to follow a path
http://rwmasters.blogspot.co.nz/2007/10/array-orderly-arrangement-impressive_30.html