Assessing the diversity of AnGR is made more difficult by the existence of many animal populations that are not assigned to any recognized breed. Even though parts of these “non-descript” populations are known to be multiple crosses of recognized breeds, some animals may belong to (relatively) homogenous groups distinguishable from neighbouring populations on the basis of identifiable and stable phenotypic characteristics (among which may be unique and valuable attributes) that warrant their being distinguished as separate breeds. Determining whether or not this is the case is one of the roles of phenotypic charac- terization and is a prerequisite for effective assessment.
