Ever heard of bears? I don't believe any of them have something that could be called a tribe (unless you redefine any form of family to be one). They simply don

Ever heard of bears? I don't believe any of them have something that could be called a tribe (unless you redefine any form of family to be one). They simply don't have a source of food that could sustain any nontrivial population in small territory. Even living alone most of there lives wouldn't stop them from finding a mate and having an offspring.