As a recurring element of fantasy rpg’s, you have the various humanoid races most of whom can inexplicably interbreed freely. D&D – as is often the case- laid down the foundations for this in its loving inclusion of everything the authors felt was cool in whatever it was they were currently reading. So we end up with hobbits, elves, dwarfs, and humans in the typical lineup. Hobbits usually get renamed for legal reasons, and elves sometimes split off into different flavors (usually woodsy and snooty). Occasionally, they’re called something different, but if you can quickly summarize them to a new player by saying, “They’re basically elves” then for the purposes of this goof, that’s what they are. We’ve seen this so often that more than one game has been fronted by ads claiming “No elves!”
We get this again and again, and the reason we keep seeing it (in addition to assumption and tradition about what makes a real fantasy game) is because we like it. “We” as something of an aggregate here. All of us like it. Most of us, at one time or another, liked it.
We like it, even if it’s a little silly biologically speaking. I know in fantasy worlds, everybody screws, and everybody breeds. Look at dragons. Horny slutty bastards willing to stick a “Half-Dragon” template on anybody and skip without making any child-support payments. But I’m dialing this in a little closer – if an elf and a human look pretty much the same, and can interbreed to give you conflicted torn-between-two-world emo antiheroes who’re not sterile mules, then how can they really be different species? Don’t let the pointed ears fool you either.
Look at what we’ve done to dogs – the Great Dane is 200 pound and taller than me when it rears up. The chihuahua can fit in a sorority girl’s handbag. There are dogs bred for superior tracking abilities. Others bred for ferocity. Others for size and strength. Others to be low to the ground. Some small and soft and yippy serve no purpose other than fashion accessory. Yet, render a dog down to its DNA (not something to do without a raincoat and eye protection) and there isn’t much difference in small and yippy and huge and chompy. If you were sufficiently dedicated to making the point, you could breed a Great Dahauhua.
What if some elder species did this sort of deliberate breeding with primitive ur-humanity?
Some they bred to be beasts of burden – strong, slow, obedient. These massive people are as big as physics allows a humanoid to be, with corresponding changes to their proportions. These are the giants.
They bred others for war – often a sporting sort of war, done for their own entertainment. These they bred for ferocity and viciousness and aggression against other men. They bred them thick and stout, and strong – non of the soft muscles and short teeth of domesticated man. These are the orcs.
Some they bred to be their seneschals and viziers, their ministers, and their administrators. They put much of their own intelligence and sophistication into these people, making them tall and elegant, fey and beautiful. They also invested them with a measure of their cruelty and their alienness. These are the elves.
Many they bred for simple service, to tend their crops, brew their beer, to see to domestic matters. These they made small and unobtrusive, but dedicated ad sometimes monomaniacal in their pursuit of their duties. These are the halflings or gnomes.
A final race was bred for craft and the construction of the Elder’s great edifices, the mining of ores and gems, and other difficult pursuits. They bred them thick and short, powerful for their size, and extremely hearty. They spared no effort breeding them for cleverness and endurance, but wasted no effort making them attractive. These are the dwarfs.
And the humans?
If allowed to freely interbreed, in a few generations, a diverse enough population of dogs anywhere in the world will eventually normalize into something like a pariah dog – yellowish with subtle patterns, smallish, with stout body and fairly short legs. Upright ears and a slightly flipped over tail complete the picture. The generic dog, the throwback creature. It is genetically diverse, hearty, adaptable.
Among the the races, humanity is the village dog, the result of unchecked crossbreeding. All the races have some measure of cultural identity even after the Elders vanished. The elders treated culture as just one more thing to breed for and manipulate, and imprinted upon their creations cultures which perpetuated the races and kept them pure. But with them gone, this has begun to break down, and some regions are wholly overrun by these ‘base men’ lacking any special capacities or unique niche, being instead mutts of all the others. One upshot of the Elder’s cultural conditioning is the almost-universal hatred for half-breeds. The ‘half elf’ will be lucky to survive childhood.
The races are all extremely specialized in some areas, badly deficient in others. Humans are not gifted but also not impaired and partake of a ‘hybrid vigor’ which makes them resistant to the diseases and weaknesses which afflict some breeds of man.
Do something like this in your fantasy world, and you can (carefully, respectfully) create resonance with real world issues of racism, cultural assimilation, cultural and ethnic identity, eugenics, and other heavy shit. That’s not always a good thing of course – sometimes you want half-elves because SHUT UP THAT’S WHY! – but it raises some interesting possibilities for worlduilding.
And there’s always the question of what happens when the Elders return and find an ugly little mongrel humping away their prize-winning Great Northern Russet-Haired Elf.