Old Hundredth by Brian W. Aldiss

Old Hundredth by Brian W. Aldiss (New Worlds #100, November 1960) is set on a far future Earth where humanity has departed and only animals are left; it opens with Dandi Lashadusa (who we later discover is an uplifted sloth-like creature) passing a musicolumn:

When old Dandi Lashadusa came riding down that dusty road on her megatherium, the column began to intone. It was just an indigo stain in the air, hardly visible, for it represented only a bonded pattern of music locked into the fabric of that particular area of space. It was also a transubstantio-spatial shrine, the eternal part of a being that had dematerialised itself into music.  p. 63

Dandi dismounts near the column to listen to its music, and telepathically communes with her tetchy mentor half a world away in Beterbroe. He ignores Dandi’s suggestion to look at the view through her eyes, and he instead provides a trenchant critique of an unnamed piece of music that is of significance to Dandi. The conversation then briefly touches on to her tentative plans to die, before she gets back on the megatherium and continues on.
As Dandi travels towards her next stop, the Involute (“it seemed to hang irridial above the ground a few leagues on”), we learn that, in this far future, the Moon has left Earth to orbit the Sun, and that Earth and Venus now orbit each other. We also learn about humanity’s expansion throughout the solar system, and their development of the Laws of Intergration, which ultimately led to the construction of the transubstantio-spatialisers used to project them onto the pattern of reality. They never came back.
When Dandi arrives at the Involute her mentor senses her dark thoughts. He tells her that moping does not become her, and that she should return home, and adds that he does not want to hear any more about the music she has chosen for her swan song. She replies that she is lonely:

He shot her a picture from another of his wards before leaving her. Dandi had seen this ward before in similar dream-like glimpses. It was a huge mole creature, still boring underground as it had been for the last twenty years. Occasionally it crawled through vast caves; once it swam in a subterranean lake; most of the while it just bored through rock. Its motivations were obscure to Dandi, although her mentor referred to it as ‘a geologer.’ Doubtless if the mole was vouchsafed occasional glimpses of Dandi and her musicolumnology, it would find her as baffling. At least the mentor’s point was made; loneliness was psychological, not statistical.
Why, a million personalities glittered almost before her eyes!  p. 68

The last part of the story (spoiler) sees Dandi arrive at her old home in Crotheria. When she goes to look at her old house she is confronted by an uplifted bear—transgressive creatures that are the only ones who wish to emulate “man’s old aggressiveness”. Dandi panics and summons her mentor (now revealed as an uplifted dolphin). He takes control of her body and moves to kill the bear, but Dandi fights her mentor and tells the creature to flee. The enraged mentor throws Dandi’s elephant-sized body against the wall and the house begins to collapse. She jumps to safety.
Dandi later realises, when she hears nothing further from her mentor, that she has been excommunicated. She continues her journey until she comes to a suitable spot, frees her mount, and proceeds with her plan:

Locking herself into thought disciplines, Dandi began to dissolve. Man had needed machines to help him do it, to fit into the Involutes. She was a lesser animal: she could unbutton herself into the humbler shape of a musicolumn. It was just a matter of rearranging—and without pain she formed into a pattern that was not a shaggy megatherim body . . . but an indigo column, hardly visible . . .
Lass for a long while cropped thistle and cacti. Then she ambled forward to seek the hairy creature she fondly—and a little condescendingly—regarded as her equal. But of the sloth there was no sign.
Almost the only landmark was a faint violet-blue dye in the air. As the baluchitherium mare approached, a sweet old music grew in volume from the dye. It was a music almost as old as the landscape itself and certainly as much travelled, a tune once known to men as The Old Hundredth. And there were voices singing: “All creatures that on Earth do dwell . . .”  p. 73

There isn’t much of a story here, and the pleasure that this piece provides comes from (a) its exotic and elegiac descriptions of a pastoral far-future Earth, and (b) its transcendent, sense-of-wonder ending. I thought this was an excellent story the first time I read it but, this time around, it was apparent that part of its charm is the novelty of its touching last line.
***+ (Good to Very Good). 4,300 words. Story link.