These dogs are known to be very energetic and alert. That might contribute to their aggressiveness towards strangers. They are also very loyal and may snap when their family is threatened.
Small dogs in the University of Helsinki's research, miniature poodles behave aggressively to make up for their size. They are very energetic, and their hyperactivity.
Miniature schnauzers are also fearless, despite their size. They won't back down in the face of a fight, which can cause normal situations to escalate.
German shepherds frequently serve as police or military dogs, but not because of their aggressiveness. Instead, it's because they respond well to training.
These medium-sized dogs, known for their woolly curls, were originally bred to retrieve downed waterfowl. That may contribute to their above-average aggressiveness.
The curly-coated Lagotto Romagnolo breed began as a truffle-hunting dog in northeastern Italy. Like other working dogs, they can be very energetic and need plenty of stimulation.
Chinese crested dogs are one of the smallest dog breeds in the world. The breed is most known for its hairless variety, which has only tufts of hair around its paws and head.
These small dogs have poofy coats and a reputation for yapping. They're devoted to their owners, but very distrustful of strangers. They can make great watchdogs.
Cotons are famous for their fluffy white coats and vocal personalities. They form very close bonds with their owners, and they make excellent companions.