Evolvable hardware (EH) is a field focusing on the use of evolutionary algorithms (EA) to create specialized electronics without manual engineering.
Done properly, over time the evolutionary algorithm will evolve a circuit configuration that exhibits desirable behavior.
The concept was pioneered by Adrian Thompson at the University of Sussex, England, who in 1996 used an FPGA to evolve a tone discriminator that used fewer than 40 programmable logic gates, and had no clock signal.
This is a remarkably small design for such a device, and relied on exploiting peculiarities of the hardware that engineers normally avoid.
Fitness in evolvable hardware problems is determined via two methods: In extrinsic evolution, only the final best solution in the final population of the evolutionary algorithm is physically implemented, whereas with intrinsic evolution every individual in every generation of the EA's population is physically realized and tested.
For example, one can buy intellectual property cores to synthesize USB port circuitry, Ethernet microcontrollers and even entire RISC processors.