Pegasi

The pegasi of the Sky Cowboy world started as regular horses, but evolved sufficiently to gain the ability of flight after the creation of the chasms. There are no wingless pegasi in the SC world, and the word for similar flightless creatures has been mostly lost to them, though some communities still remember an ancient name for the pegasus.

There are three classes of pegasi universally recognized in the Sky Cowboys world: Broadwing, Longwing, and Shortwing.

Broadwings
These pegasi are of average or medium size/weight, with large, strong wings and prominent flight feathers. Aesthetically, they are combinations of raptors like eagles, kites, and hawks, and quarter horses, mustangs, and warmbloods.

Longwings
These pegasi are lightweight and quick, with very long, thin wings. Aesthetically, they are combinations of seagulls, terns, and frigate birds and thoroughbreds, arabians, and akhal-teke horses.

Shortwings
These pegasi are large and heavy, with short, rounded wings and (generally) mild temperaments. Aesthetically, they are a combination of clydesdales, shire horses, and percherons, and small songbirds like finches, nuthatches, and hummingbirds. Due to their massive size and small wings, they can't really fly.

Breeding and Raising
Humans currently breed and raise pegasi of all three classes, though unlike the horses of our world there are still substantial wild populations on various islands. As the biology and behavior of pegasi is based primarily on that of horses, pegasus foals will nurse from their mothers for a period of 1-2 months after hatching.

The beak of a hatchling pegasus is one of the last things to calcify (harden) after hatching, allowing them to nurse for a time. When the hardening process is noticably advanced, most breeders will start to separate the foals and dams to start training and encourage weaning. The exception to this is the longwing breeds, which bear live young. These youngsters are more developed than their hatched cousins, and can usually begin eating fish and grasses within 24 hours of birth.

It is common for a breeder to have a nesting or incubation barn for easy supervision, though not all breeds will cover a nest if it's not outside. Infertile eggs (laid only once or twice a year, and not by all breeds) are collected and used as food or medicine. Several prominent superstitions hold that eating the yolk or shell of a specific breed's eggs (regardless of fertility) can have effects ranging from curing diseases to guaranteeing a human female's fertility. None of this has been tested or proven.

Interbreeding
The question "can a broadwing and a shortwing breed?" has come up several times, and the current answer is "no," though this may be changed by the author in the future.

Coat and Crest types
Pegasi, like the horses of our world, have hair on their bodies and necks, but feathers on their crests, tails, wings, and hocks. As a general rule, pegasi in cold climates will grow a thick, shaggy coat of down feathers to keep them warm, and then molt in the spring (an excellent and renewable source of down for such luxuries as pillows, blankets, and mattresses). Likewise, pegasi in hot climates will have sleek, shiny coats of fine hair, good for reflecting both the sun and its heat. Pegasi crests can also come in multiple styles, and a breeder may select their breeding pairs with this in mind.

A full crest is highly desireable, but hard to maintain, featuring long feathers down the full length of the pegasus' neck.

The half crest can be equally hard to maintain, but more expressive, as the peg may be able to raise and lower it to a limited extent.

A bald crest is common, and the lowest maintenance, often showing up in breeds with prominent markings on the face, neck and/or chest. This features only a few small feathers between the ears or down along the neck.

The bar crest can be dramatic, particularly when paired with a bright color, comprized of 2-5 long, stiff feathers extending back from between the ears, generally along the same line as the face and muzzle.

The hedge crest is the most likely for a breed that can raise and lower its crest for expression or display, and is thus prominent in more colorful or flamboyant breeds. With the 3-5 long feathers furthest between the ears, shorter and often more colorful feathers will fill out the grap between the longest crest feathers and the neck. These are usually soft to the touch, but very sensitive.

OC Creation Guidelines
A  pegasus’ size/conformation is determined by horse breed. Wing size is determined by pegasus class, which is also generally linked to horse breed. Pegasi tend to act more like horses than they do birds. They make horse sounds, but can usually also trill, whistle, and tweet. They tend to follow a horse herd social structure. Per the author: Pegasi are about 80% horse and 20% bird.