This time I want to talk about breeds. Horses, cows, dogs, cats, all are single species who thanks to human domestication have a plethora of different breeds. Here are the worldbuilding questions for yall:
Would there still be as much diversity among cats, dogs, horses, etc. without humans breeding them? For example if humans had never domesticated cats and all cats had remained wild, what would the
felis domesticus (I guessed at the scientific name, forgive me if it's wrong) species look like? I've heard somewhere what seems to be the accepted tradition that that dogs are descendants of domesticated wolves. If wolves were not domesticated into dogs and bred, would that mean greater diversity among wolves, or would dogs still be a separate species? Would horses still have the wide variety of colors or would it be more limited? Or...to look at it from a different perspective, would the peoples of your worlds have bred the same numbers and types of breeds that humans in our worlds bred? These kind of thoughts are easy ways to add interesting creatures to your world without creating new species.
For instance, if dogs in your world were only bred into three or four breeds, your prince could have a loyal hunting hound of Mastiff size but extremely lupine features, while his best friend the guard boy has a puppy that would look just like a wolf if it weren't for its Irish-Setter coloring. With just that you have crafted colorful creatures for your stories, without having created a new species.

Another thought to play with: Would the peoples of your worlds have domesticated and bred the same types of creatures the peoples of our world did? What if the peoples of your world found different creatures to meet the needs of our domestic animals? What if horses, sheep, cows, and cats had never really been domesticated in your world because its peoples found suitable replacements. I think it's easier for our readers to understand our worlds if we keep some universal domesticated animals like horses and cattle, but these are just fun thoughts to toss around in your head late at night (at least they are for me). And what if horses, sheep, cows, pigs, cats, dogs, etc. were domesticated by the peoples of your world but other animals of the world were more intentionally bred? So your world may have two or three breeds of horses and dogs and only one breed of cat, but over thirty breeds of dragons and wyverns, fifteen breeds of chimaeras, and six or so breeds of goblins (assuming that in this case you hypothetically have goblins as creatures in your world instead of intelligent people/races).
And one last area of thought to run through your heads as you wait for the sandman tonight: What would the lives/survival of our common domestic animals look like if they'd never been domesticated by us? Would sheep have gone extinct millenia ago without shepherds to protect them, would goats? Some fun thoughts for yall.
In Christ,
Jordan