You sleep under a grove of trees in a park.
At night a feral cat visits you and you feed her.
You decide to set up a makeshift shelter
with food and water for her.
Another feral cat comes for the food and they fight.
So you guild another shelter for the second cat.
Then you build a third,
and a fourth,
and more for each cat that visits.
Soon, under your grove of trees,
you have a village of shelters
and a community of cats.