My expectation is that technology will soon reach a point where we’re able to guide our own evolution through cybernetics, genetic engineering, etc. That dynamic will feed back on itself as the first generation of augmented humans influence the direction of future augmentation, so that it becomes really important who makes the first steps and why.
My pet theory for why aliens haven’t contacted us is that a species simply isn’t worth talking to until they’ve taken this step. Not only does it allow a species to achieve the advanced intelligence necessary to become their peers, but it represents a first step into “adulthood.” The species is no longer a slave to the happenstance of biological evolution, but can choose what kind of organism(s) it wants to be, what reward system will govern its consciousness, and so on.
Or, we’ll blow ourselves up. This is why we’re not hearing a lot of radio signals coming from space. In a very short time, species which reach our current level of technology either destroy themselves, or reach a technological singularity that renders them godlike. There are no Star Trek-style spacefarers out there (or, if they are, they look more like the Borg than the Federation).
