I’ve been trying to find a story about a guy who orders exotic pets from all over the universe. He orders these creatures that resemble humans in many ways but are much smaller. There are four tribes, and you put them in a kind of terrarium. You have to be careful not to let them out, because they grow to fit whatever space they are in. They will eventually fight with one another.
Of course they escape.
Anyone know the author or title?
Sounds like “Sandkings” by George R. R. Martin. They weren’t originally humanoid, but ant-like and very adaptive.
“Dreams Of My Father”?
“The Time/Life History of Liberals”?
He bought them from "Shade and Wo", a purveyor of exotic items. They were called "Sandkings" and it was written by George R. R. Martin. One of my favorite all time stories. I believe I first read it in Omni magazine years ago.