I guess we just have to wait for science to figure out when we developed spiritual souls and tell us what the meaning of life is, then.
Being that the concept of existence of a "soul" is unscientific and unproven, without any basis for existence besides the LONG history of discussing it in philosophy/theology, I wouldn't hold my breath for it's identification: it's a romantic notion that is 4,000 yrs old, at least.
The concept of soul is so entrenched in the minds of some men, it's practically impossible for some to consider it's non-existence, just like supernatural beings are an intrinsic part of many people's beliefs; to accept non-existence of God goes completely against their grain.
There is no reason to suspect that consciousness is anything but an evolutionary cul-de-sac that will never be repeated.
And the flip-side is there is no reason to suspect that it WON'T be repeated, or hasn't been repeated. In fact, the odds of it being a one-off event are MUCH LOWER than it's having happened before, even resulting in different flavors of consciousness.
In fact, look at our World: there's MANY types of consciousness, possessed by many different animals, plants, micro-organisms, etc. We haven't begun to even scratch the surface of investigating these, yet it's funny that some are chomping at the bit to travel to other Planets and search for alien life there!
BTW, evolution is largely a non-directed venture (excluding when man attempts to change it). Agreed on the objection against those who try to introduce value judgments or anthromorphisms into the discussion.
Along those lines, evolution is NOT about "survival of the fittest", as much as it's about "survival of the sufficiently fit" for a given test, i.e. those who pass whatever test(s) they encounter. Sounds circular, but it boils down to those who survive, for what ever reason, are the ones that survive to pass along their genes.
The difference is important to understand: "the fittest" implies that there are two competitors, and only one form survives, "the fittest" like in a WWF cage-match to the death. Nope, that's way too over-simplified. Instead, depending on how high or low the selection pressure bar is set, all, some, few, or even NONE may survive a given environmental condition they encounter. Selection "tests" may be relentless, periodic, or even non-existent at times.
Another element to remember is that evolution does NOT affect traits found in individuals past reproductive age, eg cataract development is NOT a trait that is subject to evolution, since cataracts occur late in life (mid-60's generally); hence any genes that effect their development or afford protection are not subject to selection pressures that might effect their frequency in the gene pool. The exception is childhood cataracts; these ARE subject to evolutionary pressure, since effected children MAY be expected to experience selection pressure (at least, in the days before cataract surgery, or even still in countries where access to such services are unavailable).
