What physical feature is described as the most defining characteristic linked to the breed's environment?

Answer

Their shaggy, weather-resistant coat

Their shaggy, somewhat harsh coat is cited as the most defining physical feature, as it was necessary for a dog spending its life outdoors to repel rain and insulate against the cold weather of northern France.

What physical feature is described as the most defining characteristic linked to the breed's environment?
raceOriginDogbreedingBerger Picard