The Earth we perceive with our physical eyes is billions of years in age. Life began to inhabit this sphere eons ago and evolved to fill the world through a process of natural selection. Several millions of years ago the ancestors of humankind diverged from our nearest surviving cousins and our basic physical form was achieved perhaps 200,000 years ago.
Unlike some of their religious contemporaries, early Mormons did not reject or fear science; they embraced it. Their cosmology (view of the universe) expanded the Biblical scope of creation to include souls on worlds without number. Their cosmogony (explanation for the universe’s origin) embraced contemporary science which held that matter could not be created ex nihilo. (The contemporary scientific “law of conservation of mass” contradicted the Genesis account but was perfectly attuned to the creation described in the Book of Abraham.)
Let me propose that Mormons today needn’t be locked into a world-view that embraces science up through 1844, and rejects subsequent advances in our understanding of geology, astronomy and biology. The understanding of the universe can be elastic, because a veil runs through it.
And there were many whose faith was so exceeding strong even before Christ came, which could not be kept from within the veil, but truly saw with their eyes the things that they had beheld with an eye of faith, and they were glad.
— Book of Mormon (1830) p. 564, (LDS) Ether 12:19, (CoC) Ether 5:19.
Gaze through the veil and picture in your mind’s eye a vision of Eden: the Pre-Mortal Earth perfected in its Celestial Sphere. All of the animals and plants are accounted for, but their condition is utterly different from the familiar mortal plane, for there is no death and no birth in the world. Mortal time itself has no place in the Garden. Placed in the world by the Gods are Michael and Sidri’el of the great ones, valiant leaders both in the Psuchemachy, the Pre-Mortal battle between Lucifer and Jehovah. As Adam and Eve, they exist on Earth and possess physical bodies in the image of their Heavenly Parents’ bodies. But Earth remains in the Celestial Sphere. No progress is possible in this timeless, perfect condition.
— Behold the Fall — a moment of cataclysm — of discontinuity —
Where once the world was whole and wholly a part of Eden, now three Spheres overlap: Celestial, Terrestrial and Telestial. They exist simultaneously together and apart — for they are separated by a veil. The world itself has experienced the Fall and its material forms have become Terrestrial and mortal. Adam and Eve too have been cast out of Eden and become mortal. They now experience time and can progress according to Salvation’s plan. They now have a future and in time their physical bodies will die. But time is linear, and following the line back, their physical existence also has a mortal past.
They are primitives and they are part of a group of humans, the first two to possess human spirits. They are not animals, but in the Terrestrial sphere their forms were now born of animals, whose roots trace back lineally through time to the beginning of mortal life. Their vantage is now grounded in Terrestrial existence. And, like their physical children (down to us), they will live out their lives with mortal eyes, glimpsing the heavenly Sphere they have lost (and will return to) only in fleeting memories and occasional visions — when God sees fit to throw back the veil.