This next breed of dog is often picked for their cuteness. Usually under a foot tall, French bulldogs always seem to be curious about their surroundings and eager to learn. Their natural disposition makes them quite easy to train. French bulldogs also bark less frequently than other breeds in their weight class. Although they require very little exercise and grooming due to their short hair, they are sensitive to certain climates. French bulldogs are unable to regulate their body temperature and need to be paid special attention to during extreme weather.