We set up firewalls to protect our online privacy; they seek out fire hydrants to sniff out their neighbors' secrets. We've got AOL; they've got pee-mail.
If the appeal of nosing around lamp posts and stop signs and every other tree on the block eludes you, try imagining it as the canine equivalent of logging on to a Web portal like Yahoo, or Netscape. Dogs have an olfactory sensing ability estimated at a thousand times greater than our own; sniffing and snuffling along any given sidewalk or well-worn walking trail transports them into a kind of sensory-driven cyberspace - a cyberspace filled with smelly hyperlinks.
Every time they step outside, our dogs are bombarded by messages encoded in the chemical compounds found in the urine of other dogs. Sometimes it's spam; sometimes it's a message from the cute Yorkie looking for love, or the Pit Bull reminding the neighborhood who's the boss (and woe to the foolhardy intruder).
A dog that's feeling poor may also report in -- much like that one friend who always calls to complain when she's down with a cold, in hopes that you'll bring over some magazines and videos.
All of this results in behavior that is, from the human point of view, incomprehensible, and even a little nuts: running around in excited circles when Madeline the Shih Tzu pads into the elevator; aggressively barking at that seemingly sweet little Scottish Terrier who looks like he wouldn't harm a flea; straining madly at the leash to go and meet the Dachshund primly seated beside her human companion; suddenly stopping in mid-trot to touch noses with a seemingly depressed Beagle.
There's a method, then, to so much apparent doggie madness: namely, the nose knows. While our own pitifully inadequate muzzles might sometimes leave us in the dark -- how's that for a mixed metaphor? -- the information our four-legged friends glean through theirs is nothing to be sneezed at, which leaves one last question: do dogs Google?