Differences Between Wolves & Dogs?

[Catherine]

We are not the only ones interested in this subject. It seems the real reason dogs have such variations is us. Humans have controlled dogs lives since they started living with us. We have selected and intentionally bred animals that have health issues. We like the trait so we keep it. In a wild population the dog wouldn't have survived.

https://www.nature.com/scitable/topicpag...eding-434/

Some natural variation did exist in wolves and in ancestral wolf and dog populations.
Mutations have occurred more recently as well. 

https://www.thetech.org/ask-a-geneticist...06/ask159/

It would take a lot of study to determine if certain traits existed in wolf populations or are they mutations that have occurred since dogs became domesticated.
It is a complicated subject. Hair alone raises a lot of questions. Variations in coat density and length probably do exist in natural populations. A heavier coat would be an advantage in a colder climate. Hairlessness however seems like a negative trait. Hairless animals exist because we look after them. If wolves had the trait it would have killed any cubs born without hair. 
Poodles don't shed. In the wild that would be a problem. We have bred sheep to have hair that must be sheared. An escaped sheep is in trouble because their hair just keeps growing.

This is going to require more research.

Why don't cats exhibit as much variation? We have been cross breeding them and cats still look like cats. Great Danes and Chihuahuas don't look like they are the same species. I will see what I can find out.