dogs-3
Explanation
The Joke
A man and a woman are walking outdoors, and the man cheerfully remarks: "Isn't it amazing how similar dogs are to humans?" The caption below the panel then reads: "Shortly before Dave rolled around in dead mice to acquire their scent."
The setup plays on the common sentiment that dogs are remarkably human-like -- they show loyalty, empathy, playfulness, and emotional intelligence. People love to emphasize the similarities between dogs and humans. The punchline flips this by suggesting that the similarity goes the other direction: rather than dogs being like humans, Dave (the human) is about to behave like a dog, rolling around in dead animals to pick up their scent -- a famously disgusting dog behavior.
The Humor
The comedy comes from the bait-and-switch. The reader expects the caption to provide a heartwarming example of dog-human similarity, or perhaps to gently undercut the claim by noting a way dogs are different. Instead, it confirms the similarity in the most revolting way possible -- by having the human act like a dog at its most animalistic. The joke also works because of Dave's smug, knowing expression in the panel; he delivers his observation about dog-human similarity with no awareness that he is about to prove it in the worst way. It is a classic SMBC move of taking a sentimental platitude and finding the most disturbing interpretation that is technically still consistent with the original statement.