Unnatural VS Natural

In the world Tolkien has created many things are natural things that we find in our world, some of those things include bees and trees which act similarly in Middle earth as they do in our reality. Tolkien does this to show that even though Middle Earth is fictional it still has similarities to our world that make it seem more tangible ad easy to visualize. Due to the world being more believable and actually something we can visualize when he mentions things like green fire or giant talking eagles we as readers feel more immersed because these "unnatural" things he adds in are basically something we would find in our world just with an added element such as color, size, ability to talk etc. In addition to this he also has a normal version of these "unnatural" things such as red/orange fire or normal sized non talking eagles. Again, I would like to emphasize that he does this because when he writes about something that we can actually visualize and believe could exist it is much easier for readers to transport themselves into Middle Earth and become apart of the story.