Dogs don’t understand human ideas of personal space. While people expect privacy to be respected, dogs rely on instinct and curiosity. As the article notes, “those ‘rules’ of respecting someone’s privacy don’t really apply to dogs.” What feels awkward to us is normal behavior for them and part of how they explore the world.
Dogs often greet others through scent, just as they sniff other dogs. What humans see as an invasion of privacy is simply “a dog’s way of getting to know someone better and saying ‘hello.’” Their noses are incredibly powerful: humans have about 6 million scent receptors, while dogs have “up to 300 million,” making their sense of smell far stronger.

Dogs also have a special structure called Jacobson’s organ, which helps them detect pheromones. Their brains devote far more space to processing scent, making them experts at detecting changes in body chemistry and even helping humans as service and medical detection dogs.

The crotch draws special attention because it contains apocrine sweat glands that release pheromones. These signals carry information about age, sex, mood, and more. Since armpits are harder to reach, “the crotch is the next best information hub for the dogs.” Certain breeds, like Beagles and Bloodhounds, find this especially hard to resist.

While the behavior is natural, it can be redirected. Experts suggest training alternatives rather than punishment, using techniques like fist targeting to give dogs a more appropriate way to greet people.