question:  Why is the story's setting important for the plot?
context: The only kind of gag worth pulling, I always maintained, was a cosmic one—till I learned the Cosmos has a really nasty sense of humor! Yet I had always been so sure I could create them that I had been calling them volplas for ten years. No, twelve. Again in the laboratory, I entered the metabolic accelerator and withdrew the intravenous needles from my first volplas. The accelerator had forced them almost to adulthood in less than a month. It would be several hours before they would begin to move, to learn to feed and play, perhaps to learn to fly. Meanwhile, it was clear that here was no war of dominant mutations. I flipped a hamburger and a slice of onion onto a plate and picked up the ketchup and said, "I've reached the dangerous age." I wiped the back of my hand across my mouth and said aloud, "Yes, sir, the dangerous age. I kissed her until I heard rollerskates coming across the terrace from one direction and a horse galloping toward the terrace from the other direction. I've only had the feeling once before in a small way, but I've always...." Outside this little town, I found a litter of flat stones that had young black-snakes under each slab. They were also much faster than had been their predecessors in organizing their nervous activity after the slumbrous explosion of growth in the metabolic accelerator. Except for the face, chest and belly, they were covered with a soft, almost golden down. The cranium was in the same proportion to the body as it is in the human. The spars had been common to the basic colony for years and were the result of serial mutations effecting those greatly elongated fifth fingers that had first appeared in Nijinsky. No longer jointed like a finger, the spar turned backward sharply and ran alongside the wrist almost to the elbow. Powerful wrist muscles could snap it outward and forward. Suddenly, as I teased the male volpla, this happened.
output:  The narrator's ranch is so big it can conceal its inhabitants.
options:  The narrator's ranch is so big it can conceal its inhabitants.  The volplas can only survive in California.  There are sparrows for the volplas to eat at the narrator's ranch.  The volplas originally lived in a similar landscape.