Why Do Dogs Yawn When You Do? The Science of Contagious Yawning

Published September 2026 -  Pet N Pet Editorial - National Dog Day Science Series

You yawn, and a second later your dog yawns too. It feels like a small moment of connection, and one famous study seemed to confirm it: 21 of 29 dogs yawned after watching an unfamiliar person yawn, while none yawned when the person just moved their mouth without yawning (Joly-Mascheroni, Senju, and Shepherd, Biology Letters, 2008).

That was the first evidence of contagious yawning outside of primates, and it launched a tempting idea, that dogs "catch" our yawns because they empathize with us. It's a lovely thought. It's also far from settled. Later studies have both supported and flatly contradicted it, and the honest version of this story is more interesting than the greeting-card one.

What the First Study Actually Found

In 2008, researchers sat dogs in front of an unfamiliar person who yawned repeatedly, then compared that with a control where the person opened and closed their mouth without yawning. The result was striking: 21 of the 29 dogs yawned in the real-yawn condition, and not a single dog yawned in the control (Joly-Mascheroni, Senju, and Shepherd, Biology Letters, 2008). On average, it took a dog about a minute and a half to catch the yawn.

This was the first time contagious yawning had been shown in a non-primate, and it made headlines. The authors were cautious in their wording. They suggested it might indicate a rudimentary form of empathy. "Might" and "rudimentary" did a lot of work in that sentence, and the pop-science version quickly dropped both.

Why the Empathy Story Took Off

The empathy idea didn't come from nowhere. In humans, how easily you catch a yawn tracks how close you are to the person yawning. Yawn contagion is strongest between family members, then friends, then acquaintances, then strangers (Norscia and Palagi, PLOS ONE, 2011). If closeness drives yawn contagion, the reasoning goes, then contagious yawning must be tapping into something social and empathic.

A 2013 dog study was built to test exactly that. Across 25 dogs, the animals yawned more in response to their own owner than to a stranger, a familiarity effect (p=0.032). And their heart rate didn't rise during the yawning, which the authors used to argue the yawns weren't just a stress reaction (Romero, Konno, and Hasegawa, PLOS ONE, 2013). For a while, this looked like solid support for the empathy account.

Then the Contradictions Piled Up

Here's where honesty matters. The empathy story has taken serious hits. First, the basic effect doesn't always show up. A controlled study using video of yawning humans found only 1 of 15 dogs yawned more to yawns than to control clips, a failed replication of the 2008 result (Harr, Gilbert, and Phillips, Animal Cognition, 2009).

More damaging, the familiarity bias, the heart of the empathy argument, hasn't held. An earlier study found no evidence that dogs yawned more at familiar people than strangers (O'Hara and Reeve, Animal Behaviour, 2011). And the largest analysis to date, covering 257 dogs, confirmed that contagious yawning happens but found no familiarity bias, no gender bias, and no link to helpfulness. The dogs even yawned slightly more at an unhelpful person. The authors concluded plainly that contagious yawning in dogs is not driven by an empathy-related mechanism (Neilands et al., Proceedings of the Royal Society B, 2020).

The Competing Explanation: Arousal, Not Fellow-Feeling

If it isn't empathy, what is it? One well-evidenced alternative is plain physiological arousal. When researchers exposed 60 shelter dogs to human yawns and measured their stress hormone, the dogs that caught yawns showed elevated cortisol afterward, while non-yawners' cortisol dropped (Buttner and Strasser, Animal Cognition, 2014). That points to yawning being tied to a state of arousal or mild stress in the moment, not to a dog sharing your feelings.

There's also the simplest possibility of all: some contagious yawning may just be a low-level, automatic response to seeing a familiar action, the same reflexive way you might yawn reading this paragraph. None of these explanations require the dog to understand or share your emotional state. They just require a normal, slightly suggestible nervous system.

So What Should You Actually Believe?

The fair summary is this. Dogs can catch human yawns, though not as reliably as the viral version suggests. Whether it reflects a flicker of empathy, ordinary arousal, or simple automatic mimicry is genuinely unresolved, and the most recent and largest study leans away from empathy.

So if your dog yawns when you do, enjoy it as a real, if modest, bit of social contagion between two species that pay close attention to each other. Just be skeptical of anyone who tells you, with certainty, that it proves your dog empathizes with you. The scientists who study this for a living can't agree on that, which is a good sign you shouldn't be certain either.

Frequently Asked Questions

Why does my dog yawn when I yawn?

Dogs can catch human yawns, shown first when 21 of 29 dogs yawn after watching a person yawn (Joly-Mascheroni et al., 2008). Why they do it is disputed. It might reflect a rudimentary social response, ordinary physiological arousal, or simple automatic mimicry. The most recent large study leans away from the popular empathy explanation.

Is yawning really contagious for dogs, or is that a myth?

It's partly supported, not a clean fact. Some studies show dogs catching yawns, but others don't, one controlled study found only 1 of 15 dogs did (Harr et al., 2009). So the effect is real but inconsistent across experiments, which is why researchers describe it as present but weaker and less reliable than in humans.

Does my dog catching my yawn mean it loves or empathizes with me?

Probably not in the way the internet claims. One study found dogs yawned more at their owner than a stranger (Romero et al., 2013), but a 257-dog reanalysis found no such bias and concluded yawning isn't empathy-driven (Neilands et al., 2020). Treat the empathy idea as an unproven hypothesis, not an established fact.

Why do dogs yawn when they're not tired?

Yawning in dogs is often tied to arousal or mild stress rather than sleepiness. In 60 shelter dogs, those that caught human yawns had elevated cortisol afterward (Buttner & Strasser, 2014). Dogs also yawn during tense or uncertain moments, which is why a yawn in a stressful situation may signal discomfort more than fatigue.

Do dogs yawn more at their owners than at strangers?

One 2013 study said yes, and it became the main evidence for the empathy theory. But later work undercut it: an earlier study found no familiarity difference (O'Hara & Reeve, 2011), and a 257-dog analysis found none either (Neilands et al., 2020). So the owner-versus-stranger difference is contested and may not be a real effect.

Bottom Line

Contagious yawning in dogs is a great example of how a charming finding gets ahead of the evidence. The core phenomenon is real: dogs do sometimes catch our yawns. But the sequel, which proves canine empathy, is exactly the part that keeps failing to replicate. The best current read is that a dog catching your yawn is a genuine but modest social contagion, driven by attention and arousal more than by shared feeling. Which, honestly, is still a nice thing to share with an animal across a species line. Just don't oversell it.

SOURCES & CITATIONS

Joly-Mascheroni, Senju, Shepherd "Dogs catch human yawns," Biology Letters 4(5):446-448 (2008). 21 of 29 dogs yawned after watching a human yawn; 0 in control. https://pmc.ncbi.nlm.nih.gov/articles/PMC2610100

Romero, Konno, Hasegawa "Familiarity Bias and Physiological Responses in Contagious Yawning by Dogs Support Link to Empathy," PLOS ONE 8(8):e71365 (2013). Owner > stranger effect (p=0.032); heart rate not elevated. https://pmc.ncbi.nlm.nih.gov/articles/PMC3737103/

Harr, Gilbert, Phillips "Do dogs (Canis familiaris) show contagious yawning?" Animal Cognition 12(6):833-837 (2009). Only 1 of 15 dogs; a failed replication. https://pubmed.ncbi.nlm.nih.gov/19452178/

O'Hara, Reeve "A test of the yawning contagion and emotional connectedness hypothesis in dogs," Animal Behaviour 81(1):335-340 (2011). Found no familiarity bias. https://www.sciencedirect.com/science/article/abs/pii/S0003347210004483

Buttner, Strasser "Contagious yawning, social cognition, and arousal... in shelter dogs," Animal Cognition 17(1):95-104 (2014). 60 dogs; yawn-catchers had elevated cortisol (arousal explanation). https://pubmed.ncbi.nlm.nih.gov/23670215/

Neilands, Claessens, Ren, et al. "Contagious yawning is not a signal of empathy...," Proceedings of the Royal Society B 287(1920):20192236 (2020). 257 dogs; no familiarity, gender, or prosociality bias. https://pmc.ncbi.nlm.nih.gov/articles/PMC7031662/

Norscia, Palagi "Yawn Contagion and Empathy in Homo sapiens," PLOS ONE 6(12):e28472 (2011). In humans, contagion tracks social closeness (kin > friends > strangers). https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0028472

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