Nonsexual mounting of other dogs is generally a dominance, control, or challenge behavior, although when practiced by puppies it’s primarily about play and social learning, beginning as early as 3-4 weeks. Mounting of humans is strictly nonsexual; it may be about control, it can be attention-seeking, and it can be a stress-reliever. High hormone levels and normal sexual responses to other unneutered dogs are different from the kind of “problem mounting” that embarrasses you in front of your in-laws or boss when they visit!
Read more: Why do Huskies mount other dogs, people or furniture?