Only 9% of the cumulative variation among dogs on the 8 behavioral factors identified can be attributed to breed.
So little (almost none) of the variability on the agonistic threshold factor (behaviors commonly labeled “aggression”) can be attributed to genetics at all that it is of no utility in predicting behavior in individual dogs.
The majority of mixed breed dogs have more than 4 different breeds in their ancestry.
Morphology varies too extensively among mutts and people typically place too much weight on associations between a few traits and specific breeds to make visual identification reliable.
The dog breed most commonly appearing in the ancestry of mutts is the American Pit Bull Terrier, which appears in the ancestry of 10% of mixed breed dogs.