As the shift occurred, some humans have had their genetic code bred to be something different and gain new traits. Like dogs used be selectively bred, so now are humans.
Some humans have been bread to have larger features such as nipples, ears and other such features. Others have had very large, noticeable changes.
The Chimans are humans that have been bred to be rather small. They can fit into hand bags and purses and are often dressed up in cute outfits. They represent the human equivalent of chihuahuas.
The furlers are humans bread to be incredibly hairy and fluffy. They were bred so they could be styled into various shapes and enter shows and enter styling competitions.
The hunter humans are humans that have been bred to be incredibly fit and muscular. Females of this breed lack the large breasts that other humans possess and are mostly flat, save for muscles on the chest.
The mulers are a large, heavy breed of humans. They are the largest breed of humans, being as large as adult shire horses and in some cases elephants. They are one of the oldest breeds of humans and were bred to be able to carry large amounts of weight on their backs and be able to pull carriages and cargo across vast distances. Nowadays, they are often used in the same fashion as horses and riding lessons to ride them exist.
The wild humans, which aren't a selectively bred breed but the natural humans, exist in the same vein as wolves did in the old world. The wild humans are slightly smaller then the average breed of humans but are much more ferocious and deadly. They are pack animals that feed of mammals and plants in woods and mountainous regions. Traits that they possess are having more fur around their crotch and arm pits, while having sharper nails and teeth.
(Please feel free to add anymore breeds if you can think of them)