"Right now I’m looking at a 3D printing device with some amazing technical specifications. (Actually, with a quantity discount, I was able to acquire six.) 

Through a high-resolution layered deposition process, it prints varied, curved-surface, three-dimensional shapes that respond to the signals it receives. The print material is high-density calcium carbonate—amazingly strong, and fully recyclable. The precise mix of this material can be adjusted, at the deposition point, to produce many different colors and textures. The forms that it produces are all of the same type, but each one is precisely customized to its particular context.

Best of all, this device is self-replicating. It can produce a new generation of printers that execute essentially the same code. This code can evolve from generation to generation, and specialists in the engineering of this sort of system are now discovering strategies to intervene with more radical reprogramming.

It is, of course, an oyster. And that’s just the 

beginning of its advanced architectural capabilities.

In addition, oysters are self-siting. An oyster larva has a light sensor (a rudimentary eye), a few actuators (cilia for swimming), an attachment device (a little sticky foot), and just enough embedded circuitry to integrate these elements into a simple problem-solving system. If this system doesn’t get eaten first, it will find a suitable place for the young oyster to grow, and then securely attach itself to that spot.

Furthermore, oysters like to attach themselves to other oysters. (Or, if you prefer, they behave like developers—simply choosing spots where it seems that predecessors have already done well.) That’s enough to initiate a self-assembly process. Over time, this process generates large oyster beds—megastructures, composed of individual living pods, that might have been the envy of the Metabolists. The shells of the pioneers form a foundation from which the bed rises free from the muck of the sea floor and into a zone of 

more abundant sunlight and nutrients. Within the structure, the shape of each unit is beautifully adapted to the shapes of its neighbors.

Once it is settled, an oyster initiates an automatic hardware upgrade and begins to respond to its environment in a new way. It gets rid of the eye, the cilia, and the foot, and activates new gear and associated logic in their place. Oyster 2.0 devotes itself to slightly parting its shells, straining plankton out of seawater, and closing up again if something unwelcome hits its gills. Simple sensors, actuators, and feedback loops of the kind that were investigated by the pioneers of cybernetics now control its responses to its changing environment. 

For creatures that scarcely have central nervous systems, this isn’t bad. Oysters respond to changes in their environment on three time frames. In real time, they open and close their shells as necessary. Over their individual life spans, they select sites and adaptively build structures that respond to local conditions. And, over many generations, they construct much larger-scale configurations that respond to longterm topographic and hydrographic patterns.

So consider the oyster, with its capacity to create huge, complex, responsively varied structures through distributed intelligence and action, selfreplication, elegantly simple principles of selforganization, and real-time connection of actuators to sensors. Through the evolution of its capabilities, it has already figured out the principles of intelligently responsive architecture.

As this book demonstrates, human architects are now starting to catch up."

William J. Mitchell, Foreword to Interactive Architecture

(thanks, Kathy)