We have seen at least a couple of Changelings mature from infant to adolescent (which Odo, with all his failings, apparently still is) and then to adulthood (which Laas may have reached), but we have little reason to think this would translate to them aging after they are done maturing. The concept of an "old" Changeling never arises, separately from or even in connection with the maturity issue.
We have seen individuals die, but nobody has discussed dead individuals afterwards, so we lack any idea whether there have only ever been something like eight in the entire history of the species, or whether Founder Heaven is just as littered with ex-individuals as any Solid one.
We have never seen an individual born. The Hundred were called "infants", as was the one that restored Odo's powers before perishing. Is this truly an apt designation, or is procreation an optional pursuit for this species, and only ever practiced in order to create scouts, messengers and assorted other cannon fodder? Since Laas reached maturity of sorts, we might deduce that Changelings do proceed from infant to adult - that is, we don't have a clear-cut reason to think that The Hundred would have been a special breed, destined to die or be killed at return, instead of becoming additional individuals to the community. But that other option certainly still exists.
We do have some reason to believe in individuals as a concept, since even within the Link there is dispute. But this might be more fluid than we perhaps think: 543 Founders may go in to form a Link, but 271 or 968 may eventually come out, and yet nobody died or was born. The material and the ideas may instead mix and match in novel ways in there. Weak kids like Odo would in this model be unable to partake, and would be treated as conventional individuals.
It's difficult to think of anything to add to the pool of known. Changelings may not consist of the type of physical matter that would be subject to wear and tear and conventional aging. Yet Odo has DNA, or instinctively imitates having that. DNA is something that would unravel with time. But replenishing in the Link is an option for true immortality, depending a bit on how an individual is defined. Does its identity reside in the matter, or in some higher dimension, or does it get recycled in the Linking process, moving from one lump of matter to another, just as easily as DNA copies itself?
The only other angle I can think of for tackling this is known history of the species. Weyoun recites the story of the creature that got uplifted for helping an early Changeling, but gives no date. Beyond this, we only know the Dominion is 10,000 years old at least (according to the propaganda) and has not faced an existential threat or even a major challenge in the battlefield for 2,000 years (ditto). Those sprouting the propaganda would not have been there, so there's no telling if their specific individual Changeling gods were, or whether their great-great-grandpredecessors were.
Timo Saloniemi
