A Different Flesh is a collection of related short stories by Harry Turtledove. Based on the idea that Homo erectus ("sims" in the text) and megafauna survived in North America, the stories chronicle the move toward the recognition of the sims as intelligent beings with rights. Originally published by Congdon & Weed in 1988, it was first published in paperback by Worldwide the following year. In 1994, Baen reprinted the book. The book includes an introduction written by Dr. Isaac Asimov. Most of the short stories were originally published in issues of Analog: Science Fiction and Fact. "Trapping Run" was originally published in Asimov's Science Fiction.