Kharakov
Quantum Hot Dog
Many humans find cars indicate intelligent design.I guess it's not the point you were going for, but I just find the concept of 'intelligent design' non-sensical.
Say that natural laws, including social forces among the intelligences that evolve, will naturally cause evolution in the system we develop.That's probably obvious to you and assumed in this thread, but once you get past that there's nothing at all intelligent or rational about life, there's no need for an intelligent designer, and asking how one theoretical 'designer' would leave clues is like .... well I don't know what it's like, but it's probably just not a very useful discussion.
Say that certain beings that evolve in the system will be curious about whether or not the system we developed was developed by intelligent beings. Do we leave hints or not?