The Intelligence of Dogs, neuropsychologist Stanley Coren, PhD, focuses on trainability as a marker of intelligence.The University of British Columbia psychology professor relied on the assessments of 110 breeds by more than 200 professional dog obedience judges who scored breeds based on working/obedience tests.The top dogs absorbed commands in less than five repetitions and obeyed them 95% of the time or better. Here's the list along with a breed description by the American Kennel Club.
Exceptionally smart and active. Bred to retrieve things from the water. The miniature variety may have been used for truffle hunting.