A thoroughly enjoyable read on an important topic.
As to this point, couldn't it be argued that human beings are also a "direct product of human creation"? We may have no conscious awareness of the exceptionally complex process that occurs following intercourse but it's possible we are somehow subconsciously manifesting the process.
Our autonomous nervous system manages many of the functions that allow us to continue living. Our heartbeat for example. Perhaps the real reason we don't have conscious control of such things is that on a subconscious level, we know survival is easier without it. Just because we don't have conscious awareness of the control we have over such things doesn't necessarily mean we don't control them. Perhaps it's just happening on a different level of awareness that we can't normally access.
If human consciousness emerges from a bed of unconscious, biological, physical matter. Why is it not possible that it could emerge from other forms of physical matter when conditions are right for the spark of consciousness to appear?