For dogs, as unusual as it can be for humans, sniffing butts is the essential way to say hello, thanks to their remarkable sense of smell.
When one dog welcomes another with a nose in the butt, it’s basically to have a quick biography of the new folk, a biography composed by fragrance molecules and pheromones.
Anal sacs are pouches located to the sides of a dog’s butt. These pouches secrete chemicals that can give a lot of information about their owner. Among this information, the sniffer dog can extract precious information about gender, reproductive status, and clues concerning health, diet, and even emotional state. For us, humans, this is an odd way to meet someone, but butt sniffing is the canine version of shaking hands, it is speaking with chemicals, and maybe the most direct way to fall in love.
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