An evolvable circuit includes a plurality of reconfigurable switches, a
plurality of transistors within a region of the circuit, the plurality of
transistors having terminals, the plurality of transistors being coupled
between a power source terminal and a power sink terminal so as to be
capable of admitting power between the power source terminal and the
power sink terminal, the plurality of transistors being coupled so that
every transistor to transistor terminal coupling within the region of the
circuit comprises a reconfigurable switch.