Gardener had been at his work for untold eons, at least that’s what he would tell people if he had anyone to tell it to. In truth, it had been 15,623 years since the last human had left, but who was counting.

When the last ship took off into the void of space, they activated Gardener with one simple directive: heal the planet of the damage they had caused. Within his memory files sat every climate record, animal population records, ocean levels, and every conceivably relevant datum relating to the planet that humans had ever recorded. At his disposal was a solar system spanning network of mining drones, solar arrays, and manufacturing facilities that could produce any desired part. There were ground and space based arrays that fed real time data into his central processing hub. There was nothing he couldn’t accomplish, the humans saw to that.

His first step was a surprising one: using his planetary drone network, Gardener went about systematically dismantling nearly all human structures. Only a few ancient structures were spared the wrath of the AI’s cutting lasers. The reasoning was simple, anything not made of stone posed too great of a biological hazard and risked further issues down the road, so it needed to be removed. Anything made of metal was melted down into ingots and stored in underground facilities for later use as needed, plastics and other general waste products were loaded up on rockets and fired into the sun, and nuclear materials were repurposed as reactors to run Gardener’s various systems. To his great surprise, The Great Cleanup only took Gardener a little over two hundred years. With that task out of the way, he was able to focus on the more time consuming tasks.

The first major step that needed to be taken was lowering the CO2 levels in the atmosphere. Not having any human industry around to pump pollutants into the atmosphere was a huge help, but there was centuries of damage that needed to be undone. While he had been sweeping away the remnants of human civilization, Gardener began a program of cultivating plant growth around the world, and focused his efforts on that. Before he knew it, fifty years had passed and saplings covered enough ground that the Amazon had been rebuilt, the ancient forests of Europe were returning, and the Sahara had been kept at bay.

With the green roads laid across the globe, the next project was helping animal populations to recover. Over the previous 250 years, some had recovered naturally, but there were still a fair number that were barely hanging on. To aide these struggling populations, Gardener made use of mobile maternity wards, large vehicles of his own design that would set up base in a habitat native to one of the endangered species to house and help nurture them while their populations recovered. With these wards animals could raise and nurture their young in peace and when the time was right, be let back into the wild as a strong and healthy adults. Part of this program unfortunately involved triaging certain species to keep there numbers in check, but this was mostly confined to species that had been classified as invasive during the time of humans. Within five hundred years, a proper ecological balance had been reached and Gardener was able to discontinue the program.

Having completed his primary directives at a far quicker pace than his creators intended, Gardener soon found himself bored. With no major projects to undertake, much of his day-to-day activities consisted of monitoring various markers of planetary health and keeping animal populations in check.

It was during one of his routine survey that he noticed something rather interesting: a troupe of apes constructing primitive shelters. Feeling what could best be approximated as excitement, Gardener found a new dimension to his mission that he had never considered: teaching up and coming intelligent lifeforms to be proper stewards and exist with the planet, rather than in spite of it.

Over the course of the next two thousand years, a method of communication was built up and a system of “schools” established. In the schools, the apes that showed the most potential for sentience were given more opportunities to mate than their less gifted brethren. While this led to some hurt feelings in the early days, progress was made and entire communities of fully sentient apes sprung up across the globe.

The sentient apes, having known nothing else, came to view Gardener as a god. While flattered, he made sure to explain to them that he was no such thing, except in the most abstract way possible. He taught the apes of their distant cousins, humans, who had created Gardener and came dangerously close to destroying all life on the planet. He used his creators as a cautionary tale and did everything that was within his power to instill the need to preserve nature into humanity’s successors.

As the apes began to develop a true civilization, a tragedy befell the planet. In an event that was several thousand years overdue, the supervolcano underneath what used to be known as Yellowstone erupted. This event triggered several other dormant supervolcanos around the world, creating a runaway catastrophe. Fires swept across the globe, huge clouds of ash blocked out the sun, and entire species went extinct. Gardner watched all these events unfold from space, powerless to offer any real help. Knowing that nothing could be done, he went went into a low power state and waited for the dust to settle.

After a several thousand year rest, Gardener booted his systems up and surveyed the damage. After the eruptions, the world entered into an ice age and most of the planet had frozen over to some degree. The great freeze had killed off most of the plant life he had worked so hard to cultivate, with nothing but the hardiest lichens able to survive in the new climate. With nothing to eat, the animal ecosystem had collapsed as well. Gone were the days of great herds of ungulates wandering the globe and various predators keeping the numbers in control.

The only major life forms to survive were found in the oceans. Whales, octopuses, algae, fish all managed to survive and thrive where others fell. Relieved to see that all was not completely lost, Gardener began to rebuild the world once again.