The Keys to December by Roger Zelazny

The Keys to December by Roger Zelazny (New Worlds #165, August 1966)1 begins with the birth of Jarry Dark, a modified human who needs a specialised environment (in his case, a temperature of -50°C and gravity of 3.2 gees). When the planet for which he has been designed is destroyed by a supernova, his sponsoring company, General Mining, provide hermetically sealed environments for him and all the other genemods like him.
The rest of the first few pages sees Jarry and the other 28,000 of his kind form the December Club: they pool their money, Jarry makes even more for them on the markets, and they finally buy their own world and start terraforming it.
The next part of the story sees the 28,000 arrive on the planet and enter cold sleep, although small groups are rostered to stay awake for short periods to supervise the twenty World Change machines and their three thousand year task.
During Jarry and his wife Sanza’s first shift, they see the effect the changes are having on the planet’s wildlife:

One morning, as they watched, they saw one of the biped creatures of the iodine forests moving across the land. It fell several times, picked itself up, continued, fell once more, lay still.
“What is it doing this far from its home?” asked Sanza.
“Dying,” said Jarry. “Let’s go outside.”
They crossed a catwalk, descended to the first floor, donned their protective suits and departed the installation.
The creature had risen to its feet and was staggering once again. It was covered with a reddish down, had dark eyes and a long, wide nose, lacked a true forehead. It had four brief digits, clawed, upon each hand and foot.
When it saw them emerge from the Worldchange unit, it stopped and stared at them. Then it fell.
They moved to its side and studied it where it lay.
It continued to stare at them, its dark eyes wide, as it lay there shivering.
“It will die if we leave it here,” said Sanza.
“. . . And it will die if we take it inside,” said Jarry.
It raised a forelimb toward them, let it fall again. Its eyes narrowed, then closed.
Jarry reached out and touched it with the toe of his boot. There was no response.
“It’s dead,” he said.

Later, Sanza expresses doubts about what they are doing to the planet:

“It’s funny,” she said, “but the thought just occurred to me that we’re doing here what was done to us. They made us for Alyonal, and a nova took it away. These creatures came to life in this place, and we’re taking it away. We’re turning all of life on this planet into what we were on our former worlds—misfits.”
“The difference, however, is that we are taking our time,” said Jarry, “and giving them a chance to get used to the new conditions.”
“Still, I feel that all that—outside there”—she gestured toward the window—“is what this world is becoming: one big Deadland.”
“Deadland was here before we came. We haven’t created any new deserts.”
“All the animals are moving south. The trees are dying. When they get as far south as they can go and still the temperature drops and the air continues to burn in their lungs—then it will be all over for them.”
“By then they might have adapted. The trees are spreading, are developing thicker barks. Life will make it.”
“I wonder. . . .”

This conflict limns the rest of the story. After they do a solo shift each, they spend the next one together, and see that the planet’s life has started to adapt. They find strange signs outside their stations. Also, around the same time, one of the other watchers develops an alcohol equivalent which they use to celebrate the millennium.
On later shifts the atmosphere has changed enough for the pair to spend short periods outside, and they see further markings outside the stations, and dead animals that appear to have been left as offerings. This latter, which occurs around twelve hundred years in, leads Jarry and Sanza to suspect that the animals they know as Redforms are becoming intelligent.
When they subsequently visit the tribe of the creatures to investigate they see several of the creatures being attacked by a large bear-like creature. Jarry kills it with a laser, and then dismounts the sled to examine the Redforms, only to be attacked by a second bear he hasn’t noticed. After he recovers from the bear’s initial blow he stabs it in the throat with a knife. At the same time Sanza drives the sled into it and kills herself in the crash. As Jarry starts walking back to the station with her body one of the Redforms retrieves his knife from the body of the bear.
On his return he wakens the executive, and asks him what he should do with Sanza’s body, as none of them have yet died on this world. They suggest burial or cremation and, when Jarry chooses the latter, they let him borrow the large aircar: he takes her to a mountain top, gets airborne again, and uses the laser to level it—the “first pyre this world has seen.” Jarry then goes back into cold-sleep.
The next time Jarry wakes (spoiler) he reads a report stating that the Redforms will die out at the current rate of terraforming. Then, when he goes to visit the Redforms, he sees they now have fire and spears, and opposable digits on their hands (the rate of evolution is the story’s one weak point). After Jarry subsequently manages to learn how to speak to the Redforms, he wakens the executive committee once more, and asks for the project to be slowed down to give them a chance. When he fails to convince them, Jarry proposes waking the membership for a vote, but no-one seconds him. Later though, after he destroys two stations, they agree. To make sure he isn’t double crossed, Jarry tells them that he has trained the Redforms to use laser projectors to destroy the remaining stations if he does not visit by dawn. One of the committee members, after realising they are beaten, asks him a question:

“Why did you do it, Jarry?” he asked. “What are they to you that you would make your own people suffer for them?”
“Since you do not feel as I feel,” said Jarry, “my reasons would mean nothing to you. After all, they are only based upon my feelings, which are different than your own—for mine are based upon sorrow and loneliness. Try this one, though: I am their god. My form is to be found in their every camp. I am the Slayer of Bears from the Desert of the Dead. They have told my story for two and a half centuries, and I have been changed by it. I am powerful and wise and good, so far as they are concerned. In this capacity, I owe them some consideration. If I do not give them their lives, who will there be to honor me in snow and chant my story around the fires and cut for me the best portions of the woolly caterpillar? None, Turl. And these things are all that my life is worth now. Awaken the others. You have no choice.”
“Very well,” said Turl. “And if their decision should go against you?”
“Then I’ll retire, and you can be god,” said Jarry.

Jarry does not go back into cold sleep afterwards, and spends his remaining time with the tribe. The story is not explicit about whether or not he gets his way, although my suspicion is that he does.
This is a very good and emotionally affecting story, and it is probably one of favourite Zelazny pieces. I’d also note that it is a work that combines his stylistic prowess with a heavyweight theme—I often find his stories are often heavy on style and poetry and larger than life characters, but are sometimes light on content. In this case, I suspect the terraforming/extinction theme was influenced by the ecology movements of the time.
**** (Very Good). 8,900 words. Story link.

1. Because this was published in a British magazine it did not appear on that year’s Hugo or Nebula ballot, but did appear on the latter when it was subsequently reprinted in the Wolheim/Carr Best of the Year. The story should probably have one or the other awards, although Harlan Ellison’s Pretty Maggie Moneyeyes would have been strong competition.