From the Summary of Cultural transmission of tool use in bottlenose dolphins:
Cultural diversity within a single population has rarely been documented. In non-human primates, the only comparable case of a subculture within a population appears to be the grooming hand-clasp of chimpanzees in Mahale, Tanzania. In contrast with non-human primates, where culture has been demonstrated by using regional comparisons between populations, the observed vertical transmission of culture with a matriline of a single population creates a different spatial pattern. Thus, the operational definition of culture used in primatology does not capture cases as described in our study. We propose, therefore, to extend this definition to "include traditions that are habitual in some but not other individuals with overlapping home ranges, within the same population, where genetic and behavioral data are inconsistent with those individuals having acquired the behavior genetically."