Within the world of Arcanum, there are three groups of races. First, the Minute Races which is comprised of the dwarves, gnomes, and halflings. Next come the Median Races, which are the humans, elves, half-elves, orcs, and half-orcs. Finally, there are the Gigantic Races, the ogres and the half-ogres.
The Minute Races
The first grouping of Arcanum's intelligent peoples are the three which I have come to call the Minute Races, these being the dwarves and their cousins, the halflings and gnomes. The Minute Races are easily recognized by their stature, which never admits of a height greater than some 50 inches or 130 centimeters, even in the largest representatives of their race. They are also recognizable by the proportions of the body, which are somewhat different than those exhibited by humans and their kin. Minute peoples tend to have heads which are larger in proportion to the torso and limbs than one would see in a human subject. The limbs, especially the legs, are also shorter and thicker.
The Gigantic Races
Ogres are the last survivors of a very ancient and potent magickal working, which has only lately begun to wane, after having been initiated nearly one million years ago. Roughly 900,000 before the present day, the fossil record shows us a wild outburst of magickal activity, an unprecedented surge of sorcery which affected life on Arcanum for millennia after. What caused this sudden cataclysmic storm of Supernatural Selection, we may never know for certain; all that we can say now is that the magickal agencies at work at that time were enormously strong, far more powerful than the forces which any modern-day mage can command. A great many organisms were created then which survive to this day, albeit in small numbers.
In this distant Epoch of Enchantment we find the origins of many legendary species, including the kraken, hydra and sea serpent; Wyrms, dragons and drakes were brought forth at roughly the same time. Many pre-existing species were substantially altered, as in the case of the unicorn and the firebird; others were merged into chimeric organisms like the centaur and manticore, for reasons unknown. Humans, which pre-date this Epoch by some two hundred thousand years, were not left untouched by the general pandemonium; although the majority of our forebears went on unchanged, some of them were vastly transformed by magick. When the fantastic whirlwind of Supernatural Selection died down some four thousand years later, two new species had emerged, and thereafter co-existed with ordinary humanity: these being the elves and the giants.
True giants are no longer among us. We know that they existed; we can still see the cyclopean stones which they arranged in the Dark Fens, if we care to travel there, and visitors still come yearly to the Giant's Dance of Morbihan to see the pillars they erected to mark the dawning of the Midsummer sun. We have also found their fossilized remains, and one or two impressive skeletons have been assembled at Tarant's Museum of Natural History. But the giants of Arcanum left behind more than their bones; they still walk among us, in the form of their living descendants, the ogres and half-ogres.
The Median Races
It is in the classification of the Median races - orcs, elves, humans and hybrids thereof - that my theories on Natural and Supernatural Selection always meet with the most resistance. I have no illusions in this matter; the religious beliefs of many are at stake, as well as a host of assumptions which are regarded as unassailable truths by the vast majority of our civilization. Nonetheless, I am a man of Science, as are my fellows in the fields of Natural and Supernatural History, and I must make my judgments based on evidence, not wishful thinking.
It is therefore my painful duty to state that all the median races, including the orcs and elves, are descended directly from human beings, by a process of Supernatural Selection. The evidence which has accumulated in recent years, through the science of Paleontology and the art of Forensic Alchemy, leaves this matter in no longer in any doubt.
Such a statement, simple as it is, sets all former systems of classification on their collective ear, and also directly contradicts the teachings of countless religions. Those who have been pleased to associate various races with mystical "Elements" will not be glad to know that their theories are not supported by the fossil record we have available. And even those learned readers who are able to tolerate speculation on the origins of mankind will often balk when we turn the same scrutiny on orcs and elves. The premise most difficult to accept is this: two organisms cannot create offspring together unless they are closely related. Although every naturalist and farmer knows it, we are reluctant to accept the same premise when it is applied to ourselves! It is nearly impossible to make the average elf, orc or human accept the truth: the very fact that half-elves and half-orcs exist at all must mean that we are cousins to one another. Further more, the fact that both half-elves and half-orcs are fertile, viable hybrids, rather than sterile sports, means that the relationship between the parent species is very close indeed!
An extremely rare orcish-elven hybrid, known as the Ren'ar Siamese Twins, is mentioned. They were created through artificial selection. Their skulls can be found in a Tarantian warehouse.