ABSTRACT
Sustainability is really quite a simple concept. Literally, it relates to the capacity to continue indefinitely. The Earth is a prime example of a sustainable system, its ecosystems having evolved over billions of years to maintain physical resources in perpetual cycles through the net capture of solar energy. The waste products of each link in its complex and intertwined food chains, which comprise the biosphere, form the food for subsequent links in those chains. Not only is the Earth an excellent example of a natural sustainable system, it is also highly pertinent to understanding what sustainability means for humanity.
