Important Species Information, Part One: Canon Species · 1:44am May 5th, 2013
I have a very detailed head-canon for my MLP fics, and since it's going to come into play here pretty soon for Her Dark Inheritance, I thought I would post this useful guide, that I refer to when I'm worldbuilding, for anyone who's curious. Keep in mind that this is just my own headcanon, and not all of this will necessarily appear in this story, but might in later stories, or might never show up at all.
Ponies: Earth ponies/Pegasi/Unicorns- obviously all can interbreed and produce offspring. They have a large presence in this world, dominating Equestria, the Crystal Empire, Prance, and Neighpon, as well as having a sizable minority population in Saddle Arabia. In sheer numbers, they technically are the most common species in the world, and in present times generally have a good relationship with their fellow species.
Zebras: can interbreed with ponies and donkeys. Mostly live in Zebrica, although in recent years some have set up in mostly larger Equestrian cities- Manehattan, Chicacolt, Las Pegasus, etc. My rationale for why the Ponyville ponies didn't know what Zecora was in Season 1? Just like people in smaller, rural towns don't always know what's going on in the world, ponies in smaller, rural towns don't always necessarily know what's going on in THEIR world.
Griffons: Live largely in their home country of Griffindell, although some live in Zebrica, some live in Equestria, and there is a population in Prance. While in prior eras they were very warlike and often preyed on other species, they no longer do so, eating non-sapient animals for food and adapting vegetables and fruits to their diet. Griffindell is probably one of the most powerful countries in the world, after Equestria and the Crystal Empire. Although rare, male griffins can sometimes mate with a female pony and produce a hippogriff, although this is extremely uncommon.
Diamond Dogs: Live mainly in Equestria, although there are some groups in Zebrica and Austroolia. .Generally they fall into one of two groups: violent, lawless barbarians, or law-abiding but mistrusted due to the reputation their species has. Some Diamond Dogs have a minor magical ability for geomancy and lapidimancy. They do have a university in modern times, and there are several successful examples of their species, but mostly they keep to themselves. They have a tribal structure, with an Alpha Dog, the Alpha's family, the Betas, and the Omegas. Please note this is not the “alpha/beta/omega dynamic” trope that is common on some websites- it is more akin to a caste system than anything sexual.
Changelings: Live pretty much everywhere. While in some fics, changelings are shown as being reproductively compatible with other species (namely, ponies), I don't hold to that theory. In this world, they are more like bees than mammals- one queen, anywhere from 100-10,000 workers (sterile females) a few hundred drones (males), and a handful of princesses. When a princess reaches of age, she leaves her hive and begins her own. When it is time to mate, drones fly to different hives to spread their genes, then die afterwards. I probably won't focus on them too much in my fics other than a passing mention here or there- this universe is complicated enough without me throwing in changelings.
Dragons: live wherever they want to, although they originate from the Draco Archipelago, a group of volcanic islands. They are not immortal like the alicorns, but can easily live for 1000+ years. Unlike most species they do not really have a system of government- the Draco Archipelago has laws like every other nation, but since most dragons do not live in their ancestral homeland they usually live under the rule of law of their adoptive countries. Spike, for example, is considered an Equestrian citizen- he was hatched there and his “mother” is a mare, not a dragoness. Garble would be considered Equestrian as well under the laws of both the islands and Equestria, although he wouldn't consider himself to be so.
Buffalo: Only found in Equestria, live in tribes. Their lifestyle was pretty well-described in show, so I don't plan to change much about it. In prior eras they fought frequently with ponies, but currently get along relatively well. Equestria mostly lets them handle their own business internally.
Donkeys/Mules/Cows: Live pretty much everywhere in this world. They never really had their own nations or systems of government that anyone can remember- there are a few legends about powerful members of each species, but most have been unconfirmed or discredited. They, out of all of the species, do not really have a history of clashing with the others, outside of the occasional conflicts. While the griffons and the ponies have been at war, or the buffalo and the ponies been in conflict, or zebras clashing with Diamond Dogs, donkeys, mules, and cows have never been in direct conflict with the governments of any of the other species. Occasional conflicts, sure, but never an all-out war.
Minotaurs: I don't know a whole lot about the mythology behind the minotaurs from the Greek myths, other than that they were the result of a union between some deity and a cow, and that the minotaur in mythology was a non-sapient monster. Obviously, minotaurs in this world are sapient, but it seems that a lot of ponies are terrified of them. I am going to go with the theory that they were a very isolated species until relatively recently, so ponies have not had much of a chance to really get to know them at all- maybe something I will explore in a future fic.
Stay tuned next time for the groups of species that have NOT appeared anywhere in canon, but that I've added. It will be somewhat shorter than this, and feel free to ignore if you don't care. :)