Another property of the agent is that all (pre-programmed) behaviors are distributed throughout the architecture. This inherent distribution was used to specialize the effects of several modules, resulting in the addition of learning and planning to the more primitive capabilities of the basic subsumption architecture.
The subsumption agent relies completely on the world for information. There is no explicit knowledge representation -- no global representation of state nor any underlying symbol level. "The world is its own best model".
The hormonal control modification to the subsumption agent gives the agent several new capabilities.