In Tolkien's universe there are examples of evolution (e.g. hobbits originate from humans) as well as creation (e.g. dwarves made by Aulë).
What do we know about Tolkien's personal opinion concerning creation and evolution? And how did his opinion on this matter affect his work?
That Tolkien was a Creationist (of some sort) is indisputable; consider Letter 96, for example:
As for Eden. I think most Christians, except the v[ery] simple and uneducated or those protected in other ways, have been rather bustled and hustled now for some generations by the self-styled scientists, and they've sort of tucked Genesis into a lumber-room of their mind as not very fashionable furniture, a bit ashamed to have it about the house, don't you know, when the bright clever young people called
The Letters of J.R.R. Tolkien 96: To Christopher Tolkien. January 1945
That does not, however, necessarily mean he was against biological evolution, so long as the act of creation was still divine; that's essentially what Theistic Evolution is. What's more, there are explicit references to evolutionary processes in his writings; Hobbits being descended from Men is one example, as is this passage from The Hobbit:
[Bilbo] could not swim; and he thought, too, of nasty slimy things, with big bulging blind eyes, wriggling in the water. There are strange things living in the pools and lakes in the hearts of mountains: fish whose fathers swam in, goodness only knows how many years ago, and never swam out again, while their eyes grew bigger and bigger and bigger from trying to see in the blackness
The Hobbit Chapter 5: "Riddles in the Dark"
In an essay published in Morgoth's Ring, he expresses the opinion that growth and change are inherent natural processes, placed there by the Valar during their creation1:
When [the Valar] perceived that Melkor would now turn darkness and night to his purposes, as he had aforetime sought to wield flame, they were grieved; for it was a part of their design that there should be change and alteration upon Earth, and neither day perpetual nor night without end.
History of Middle-earth X Morgoth's Ring Part 5: "Myths Transformed" II
And, in a footnote on that passage:
For it is indeed of the nature of Eä and the Great History that naught may stay unchanged in time, and things which do so, or appear to do so, or endeavour to remain so, become a weariness, and are loved no longer (or are at best unheeded.
History of Middle-earth X Morgoth's Ring Part 5: "Myths Transformed" II
As our good friends at Christianity.SE tell us, there's not necessarily a contradiction with being Catholic and accepting evolution; quoting from an answer to that question (in turn quoting a statement by Pope Pius XII:
[The] Teaching Authority of the Church does not forbid that, in conformity with the present state of human sciences and sacred theology, research and discussions, on the part of men experienced in both fields, take place with regard to the doctrine of evolution, in as far as it inquires into the origin of the human body as coming from pre-existent and living matter - for the Catholic faith obliges us to hold that souls are immediately created by God.
Although this was published in 1950, while Tolkien was nearing completion on The Lord of the Rings, it seems unlikely that this was a radical view of the time.
Pope Pius' statement is quite similar to the theology of Middle-earth, where growth and change (and subcreation by lesser beings than Ilúvatar) is possible, but the "soul" still ultimately comes from God.
1 Really sub-creation, since true Creation is again the exclusive purview of God
This can mostly be seen in two of his later Middle-earth writings, "The Converse of Manwë with Eru" and "The Primal Impulse".
To perceive the patterns, and their kinship, through living variation is a chief delight of those who survey the wealth of the living things of Arda. Neither is there a fast distinction between “kinds” and the variations of individuals. For some kinds are more akin to others in pattern, and may seem to be only variations of some older and common pattern. This the Valar say is how the variety of Arda was indeed achieved: beginning with a few patterns, and varying these or blending pattern with pattern.
The Nature of Middle-earth - "Elvish Reincarnation"
For it is clear in such lore as we have received from the Valar that they set in motion the unfolding of different living patterns at many different points in the Ainulindalë, and therefore this was repeated in Eä. Within Eä we have then not one single Ermenië or Great Pattern, but a number of early or Major Patterns (Arkantiër). ... Their number none but the Valar can know. These are not rightly called “akin” (unless by later mingling), for they are related only as proceeding from the same mind (as of one Vala) or from like minds (as of more than one of these), and their differences are given not developed within and by the operation of Arda. But these “major patterns” (arkantiër) developing in Arda will diverge whether by the design of their beginners, or by the varieties caused by the stuff of Arda which they must use, into different but similar groups of descendants. These are truly akin and members of races or tribes or families or houses. At last and in our time it is beyond the skill of any but the Valar to distinguish the likenesses due to the likeness of the minds of the Valar from those due to descent in Arda.
The Nature of Middle-earth - "The Primal Impulse"
Carl Hostetter explains this as such:
A long-standing feature of what has come to be known as “young-Earth creationism” is the belief in “special creation”: that is, that the first living things in all their species were created, if not “at once”, nonetheless within a short period of time. This belief was (is) rooted in a literal interpretation of the creation account of Genesis, such that all varieties of life were created within a span of four days. Coupled with commitment to a theory of invariable, immutable forms, there is no time or mechanism available for any sort of descent of species: all species must therefore have been directly created by God at the beginning of the world.
Tolkien’s theory of patterns (forms) here, on the other hand, allows both for beginnings at different times of various species, from a variety of patterns (though always subordinate to and ultimately derived from Eru’s own Great Pattern, and subject to the will of Eru), and even for their change, by blending or divergence, over time. (A time greatly lengthened by the alteration of the length of the Valian Year, though of course still nothing like geologic time.) It should be noted that this sort of theistic evolution is not the same as what is now commonly called “Intelligent Design”, one form at least of which has God repeatedly intervening in time to shape and guide the development of species. Rather, the ability of patterns to blend and diverge over time is in a sense “built into” them. (Note that the term evolve itself, in origin and in this context, indicates a “rolling out” of some inherent potentiality already possessed by a living being, or in Tolkien’s terminology, that “unfolds” over time.)
The Nature of Middle-earth - "Appendix I: Metaphysical and Theological Themes"
The books were written as Christian mythology, creation etc. But:
Tolkien once described The Lord of the Rings to his friend, the English Jesuit Father Robert Murray, as "a fundamentally religious and Catholic work, unconsciously so at first, but consciously in the revision."source
Also:
In C.S. Lewis and evolution (www.creation.com) Peter Barnes writes, "Theologically, Lewis described himself as an Anglican...He is often regarded as suspect in his views, especially regarding the doctrines of revelation and the atonement. Certainly, Lewis retained some liberal elements in his thinking..." In other words, by thinking for himself, he was a heretic. He was converted to Christianity by J.R.R. Tolkien of Lord of the Rings fame.source
Both Tolkien and C.S. Lewis were Christian and creationists.
Most discussions of J. R. R. Tolkien and C. S. Lewis stress their kinship--their shared faith, their similar scholarly interests in literature and language, their mutual love of myth, legend, and heroic romance. Scholars have tended as well to note similarities in the distinguished corpus of fantasy literature created by Tolkien and Lewis.source
Tolkien's theory of Sub-Creation
The doctrine of sub-creation was especially congenial to Tolkien, both as a Christian and as a fantasy writer. As a Christian, Tolkien could view sub-creation as a form of worship, a way for creatures to express the divine image in them by becoming creators. As a fantasy writer, Tolkien could affirm his chosen genre as one of the purest of all fictional modes, because it called for the creation not only of characters and incidents, but also of worlds for them to exist in.
As far as I am aware from reading a biography on Tolkien he was an devout Catholic after his father. The book I read never spoke about his personal beliefs in regard to this kind of thing, however in general (especially at the time of Tolkien) the Catholic church believes strictly in Genesis creation.
There are some similarities between biblical creation and how Eru Ilúvatar created the Ainur and they in turn created Arda (of which Middle-earth is a part). Read The Silmarillion for more detail, I don't know all of it off the top of my head :)
