Now that I've discussed how dwarves procreate, a few brief words on the question of elven reproduction.
So far as anyone knows, elves are immortal. They can be killed and certain ailments may slay them, but they never die of old age. All elves, regardless of their chronological age -- and many elves claim to be over a thousand years old -- look as if they were approximately in their late teens or early 20s from a human perspective. Interestingly, elves, unlike most other races, cannot be raised from the dead if slain.
Elves are few in number; most humans have never seen more than two or three elves their entire lives and rarely do they ever see more than one elf in the same place. However, there are communities of elves in isolated parts of the world but humans rarely see them, let alone visit them. Those few who have visited them note, among other things, that there are no children to be found among the elves.
This lack of children has led to speculation about how new elves come to be, if indeed they do at all. For their part, elves refuse to broach the subject with "ephemerals," implying only that it is an intensely personal matter that they do not discuss with non-elves. One popular belief is that elves are a dying race that will pass away forever when the last elf is slain. Another even more popular belief is that elves steal human children and raise them as their own. Others say that one can become an elf by consuming their food, a notion made more plausible by the fact that elves do not consume human foodstuffs if they can avoid it and prefer not to eat in the presence of non-elves, regardless of the menu.
In general, elves are a detached, almost emotionless people, at least by human standards. Though there are many tall tales of "half-elves" -- the result of a star-crossed romance, usually between a human hero and a beautiful elven maiden -- there's no evidence that such a thing is even possible. For their part, elves take no interest whatsoever in humans (or any other race) as objects of affection. Furthermore, though elves do have two genders that, outwardly at least, resemble those of humans, elves do not marry or form pair bonds or have any other kind of social arrangements that suggest either the formation of families or indeed any purpose to the physiological differences between the genders. It's almost as if elves were male and female in imitation of humans, a theory that seems unlikely given the antiquity of the race and the fact that they originated on another world.
Thus, how -- and if -- elves reproduce remains a mystery to all but the elves and they're not telling.