I’ve seen posts going around claiming that petting animals is basically tricking them into thinking they’re being groomed, and it’s bugging me because, like, there’s no trickery afoot. Petting and scritching are grooming activities. They help to dislodge loose fur and foreign objects and more evenly distribute protective oils, among other things. Primates are social groomers, and the human impulse to scritch is the legacy of our primate ancestors. We see an animal we like, even a dangerous one, and the monkey brain says “groom that thing”.