Now no, there most likely isn't genetic material, or anything else in real world science that comes into play. But play along, if you will. Consider me a "scientist" in the TES world, as in I am a character. I am simply showing that for my world, evolution exists, as we (the tes universe) know it.
Okay, hopefully that's well established.
Time, pressure, variation; the three criteria for evolution.
No, TES doesn't evolve the same as our world does. But there is time. There are pressures. But are there any actual variations? Obviously, but to what extent, and what "genetic" material would be passed on through proliferation? "Point" is that change happens. A common misconception about evolution is that things are forced, or are evolved by choice. But it is merely coincidental. There's absolutely no control whatsoever, except for the pressure. But even then, it's still coincidental.
I am not going to go crazy about real life science with TES. That's silly. However, I will draw correlations.
Time is irrelevant, more or less (assuming one has a basic comprehension of lore). So let's move to pressure. There is no natural pressure based on predatory vectors, prey, or anything else. Maybe small variations such as thicker skin, taller, shorter, etc would come into play in environments that add pressure. I mean, you probably wouldn't want a seven-foot tall Bosmer, would you? Which goes to say that organisms of a race (though perhaps species, given the maternal racial based offspring, the races can reproduce with eachother, but the offspring more often than not is the race of the mother) are not identical. You do have variation. And seemingly, you have generations of, say, fighters who are better than other familial generations who aren't as adequate. Those bosmers, sans magic (let's assume this specific group isn't adept at magic) would be more adaptive towards an environment that calls for fighting, struggling, etc. We have seen, I believe, similar things in the games. And while perhaps not detectable, the offspring, aside from being the maternal race, would also have features that resemble them.
But perhaps to go further back, before someone OTHER than Darwin who coined evolution... Darwin's theory was "Descent with modification." And that is all I am trying to merely show, that for whatever reason, there is "evolution" within the TES universe, despite all the "It's magic, Please continue, my good sir. ABOUT REAL WORLD BLAH BLAH BLAH." people. Which, to blast, even MK replied to a topic, and partly to a post of mine, before.
To go a step beyond and provide a list of scenarios:
You started with, say, one Elven race. This has become several that still exist today, and some that are presumed wiped out or merely disappeared. Now, the causes? I'll be honest, I don't remember them all, I'm not much of a Bosmer lover, lol. In fact, I kinda hate them. I'm an Altmer man. But that's extraneous. Back on topic - I do know the story of Dunmer. The time isn't important, and the variation doesn't exist until it happens. But that's one of the things I'd like to enforce. In TES, evolution can and is magical. The Dunmer pressure was Azura. That is what pressured them to change. And it was magical.
Or take the Orsimer, for example. A similar thing happened with them. Both had a pressure, the variation and time being unpresent or not important because it was caused by magic.
Or we could swap the Dwemer in. Now, I don't know how they came about, and it is theorized that, generally, with exceptions, that Elven races are evolved cultural, rather than physical/genetic, I.E. Chimer or Ayleids (though I think they had differences in appearance too, distinct ones. So one has to wonder why?). But back to Dwemer. There's a noticeable difference in their physiology, as is the same for Altmer and Bosmer.
And, we could definitely say that since the Mer races have different racial bonuses (though in-game, they are also present in lore as a race, with some being more swift, etc), they obviously have biological* differences.
(*Please keep in mind I am not suggesting genetics, etc, but that there are undeniably differences between races, for whatever the reason)
Or the race of Bretons, who are the product of Mer and man. It's a little more far-fetched/touch and go, because they're offspring of two races, but in this case, the pressure would be the parents.
And lastly, because I am going to sleep and losing my thought, for those who want to bring up the souls, etc, none of that matters? I mean, why would it? They exist, but I wonder about how much of a part they play.
So anything else to add to the idea? Bearing in mind I am keeping out like 99% of the science, while mostly using the theory or application. Or maybe you hate the idea, and by proxy me? lol