Jack of Harts

Our early colonies were started by between ten and twenty thousand people. That is a large town or a very small city with an entire world to spread out in. Most of them obviously stayed close to each other where they would be less likely to become food for whatever predators lived on those worlds. And unlike what early scientists had believed, the local predators were perfectly happy to snack on us. Their DNA structures and our own were completely compatible on every world we colonized. We could eat the local plants or animals, and they could eat us. So not only were our colonies cut off from all communication and support from Earth, they were also at effective war with the local wildlife that considered humanity to be exotic snacks. They soon learned that we were very dangerous food.