In particular, this paper details an unconstrained, intrinsic HE experiment where a network of transistors sensed and utilised the radio waves emanating from a nearby PC. Essentially, the EA led to the construction of a radio. This is, as far as the authors know, only the second example of a physical device whose sensors were constructed by a process analogous to that of phylogenetic change. We compare the circuit to the first device constructed in this way: Gordon Pask's electrochemical ear [12]. We argue that both of these devices display three key characteristics: they were constructed and tested in real environments; their basic primitives were not constrained to experimenter specified functional roles; and the primitives were sensitive to a wide range of environmental stimuli. We highlight the difficulties in implementing comparable processes in simulation and argue that only unconstrained physical systems situated in real-world environments can ever construct novel sensors in a way analogous to the phylogenetic process found in nature.

http://www.duke.edu/web/isis/gessler/topics/evolved-radio.pdf

[12] http://www.pangaro.com/pask/pask%20physical-analogues-to-growth-of-a-concept.pdf