An interesting case is where a human does the selection; this was pretty well covered in Dawkin's 'The Blind Watchmaker' [0] with his program for generating biomorphs. Some nice speculation in there too:
'Dawkins speculated that the unnatural selection role played by the user in this program could be replaced by a more natural agent if, for example, colourful biomorphs could be selected by butterflies or other insects, via a touch-sensitive display set up in a garden.' (from the wikipedia article).
'Dawkins speculated that the unnatural selection role played by the user in this program could be replaced by a more natural agent if, for example, colourful biomorphs could be selected by butterflies or other insects, via a touch-sensitive display set up in a garden.' (from the wikipedia article).
[0] https://en.wikipedia.org/wiki/The_Blind_Watchmaker