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Evan MacLean and colleagues evaluated behavioral and genetic data from over 14,000 dogs, representing more than 100 breeds, and found that variations in behavior between breeds can be attributed to genetic variations between those breeds, suggesting a genetic basis for breed differences in behavior. This was the case for both separation problems and dog rivalry but was especially pronounced for attachment and attention-seeking, which can be seen when a dog solicits affection or attention. In a different study, researchers found that, with regard to attachment and attention-seeking, the French bulldog behaves in notably different ways than the cairn terrier. Together, these findings imply that

the French bulldog and the cairn terrier differ with with respect to the he genetic underpinnings for attachment and attention-seeking.

the French bulldog and the cairn terrier will likely become more genetically similar over time.

French bulldogs and cairn terriers show a greater tendency toward attachment and attention-seeking than most other dog breeds do.

individual French bulldogs may display higher levels of attachment and attention-seeking than individual cairn terriers.