Everyone with a dog has lived this moment. Your dog latches onto a visitor’s leg, or a cushion, or another dog at the park, and starts going at it. You apologize, you laugh in that strangled way, you pull him off. What nobody does is ask what the humping actually means, which is why almost everyone gets the answer wrong.
Marc Bekoff, professor emeritus of ecology and evolutionary biology at the University of Colorado, has spent a career studying animal behavior, and his position is unglamorous. Humping is ordinary dog stuff. The meaning lives entirely in the circumstances: who started it, who received it, what happened in the ten seconds beforehand, where everyone was standing.
The data does not support your theory
Bekoff and a crew of citizen scientists logged 312 mounting incidents involving around 40 dogs at local parks, which is a genuinely uncomfortable amount of time to spend watching dogs at a park with a clipboard. Males were responsible for 58% of them, females 42%. Body size turned out to be irrelevant.
Here’s where it falls apart for the amateur behaviorists. In roughly 65% of cases, researchers concluded the dog had simply drifted into a physical position and instinct did the rest. No agenda. Play explained another 26%. And dominance, the explanation basically everyone jumps to first, accounted for about 9%.
It’s stress, not a power grab
Dr. Karen Sueda, a board-certified veterinary behaviorist at VCA West Los Angeles Animal Hospital, told Vetstreet that a dog working on your leg is almost never staging a coup. She reads it as displacement behavior, the canine equivalent of jiggling your knee in a waiting room. Feelings pile up, the dog has nowhere to put them, and something has to give.
A stranger arriving at the door will do it. So will a chaotic day at daycare, or the confusing emotional cocktail of being told off by someone you love. Owners typically reach for neutering as the solution, and it frequently disappoints. Testosterone can linger for as long as six weeks after surgery, and if the dog was already at it beforehand, hormones may have stopped being the driver a while ago. By then it’s just a habit with a long history.
And then there’s Reggie
Some dogs are simply committed. Bekoff describes a dog named Reggie whose owner reported that he went after water bowls, beach balls, other dogs from whatever angle presented itself, and human legs, at any hour. Turned down, Reggie moved on without visible distress.
Bekoff also raises a possibility that should quietly humble every owner: the dog being mounted may be issuing an invitation you cannot detect. Smells, sounds, small visual signals. The dogs are having a conversation. You are not in it.
So the next time it happens, skip the apology and look at what just occurred. Reggie’s owner never worked it out. Reggie, for his part, never appeared to want an explanation.