[jallanite]

Originally Posted by Inziladun

It's difficult to say for sure. Huan apparently wasn't part of a particular species of talking, super-intelligent dogs, instead being a singular creature.

That Huan was ‘permitted’ to speak with words only three times in his life is all we are told. This is an enchantment in the style of a folk tale, not concerned with the logic of the real world in which dogs (nor apes) cannot mentally control their larynx and tongue sufficiently to allow words to be created. One can speculate that in actuality Huan was permitted to use mental telepathy only three times or that the nervous system of his larynx and tongue could only be magically enhanced three times or might imagine other imaginings. Tolkien never explained and so there is no answer.

Yet, why a Maia would choose that specific form is a puzzle. Boredom?

That all living beings in the Undying Lands were Maiar (outside of the Valar and Elves) is a dubious idea. Each spider, caterpillar, tree, blade of grass, or microbe in the Undying Lands is in origin a Maia? It is also possible that the beasts and plants (and microbes?) of the Undying Lands were immortal, living beings distinguished from the Maiar. Tolkien does not get into that at all.

So the Ents were "spirits" that had come to inhabit bodies in Arda. They were not mortal, and Maia appears to fit the bill for their identities.

Men and Elves also are explained as spirits that come to inhabit bodies in Arda. Possible differences between types of spirits and their origins is also something that Tolkien mostly does not discuss.

Nowhere does Tolkien indicate that Ents were “not mortal”, just that Treebeard is one of the first Ents and is still alive at the end of the Third Age. Tolkien writes:

When the Children awake, then the thought of Yavanna [the thought she has just expressed] will awake also, and it will summon spirits from afar, and they will go among the kelvar and olvar, and some will dwell therein, and be held in reverence, and their just anger shall be feared.

The reference to “spirits from afar” may mean spirits from beyond Arda, spirits similar to those sent by Eru to inhabit the bodies of Elves and Men. It is possible that those spirits that are to dwell among the kelvar become the Ents and those spirits that are to dwell among the olvar become the Huorns. But the spirits who dwell among the kelvar may (also?) refer to a sprinkling of intelligent and speaking beasts and birds, such as the raven Roäc son of Carc in The Hobbit.

On the physical level the coming of these spirits into Entish forms would be when Elves first awakened the Ents.

The fact that Huan seemingly wasn't subject to mortal death either might bolster the idea that he was a similar being fundamentally.

Huan was a beast from the Undying Lands given by Oromë to Celegorm and as such might be expected to be immortal (like the Elves), regardless of his origin. One might expect that there were more than one such dog and more than one horse in the Undying Lands. Tolkien seems to imagine all spirits, whether Valar or Maiar or spirits embodied in Elves and Men and in some beasts, to be from beyond Arda.

As to spirits embodied in Orcs, Tolkien had grave problems with those.