Lots of people go to New York City at Christmastime. There's a lot to see: the lights, the window displays, the tree at Rockefeller Center. (Like most celebrities, it's not as tall as you expect.)

I was most fascinated by the wildlife. And by wildlife, I don't mean the Rockettes. I mean the rats.

I've ridden the New York City subways a fair amount over the years, but I have seen only one rat. It was on the track bed at a station in Queens, looking to escape the Manhattan rents.

This trip, in the space of three days, I saw seven. I don't know whether more rats are moving to New York or they're spending less time online, but they were definitely out and about at the close of 2009.

Six of the seven rats I saw were busying themselves down among the tracks; the seventh was on a platform, scuttling toward a staircase, which it began to climb. I had the impression it had missed its stop.

The standard-issue rat goes by many aliases: Rattus norvegicus (Norway rat), brown rat, wharf rat, city rat, alley rat, house rat and sewer rat. Or the more colorful subway-specific nickname, "track rabbit."

(Is anyone else surprised to hear the Latin for rat is "rattus"? That's almost too Wile E. Coyote to be believable.)

Honestly, I thought they were kind of cute. Yes, yes, they eat garbage, live in grime and carry diseases. And you've never had fast food or given someone a cold?

I did a little research and found that rats have a following of grudging fans. They are, after all, the ultimate survivors. One subway blogger even claims that the rats' fur has, over the decades and generations, actually evolved to match the color of the ambient filth on the track beds.

The Urban Legends Reference Pages (Snopes.com, font of truth and scourge of Internet twaddle) says this: "Rats ... are for the most part intelligent, quiet, clean, sociable and even affectionate." So saying you married one isn't actually an insult.

Snopes goes on to debunk the idea that any city has as many rats as people, dismissing such vividly creepy aphorisms as "You're never more than six feet away from a rat."

(This is true only in legislative chambers.)

The reality check comes from a book by Robert Sullivan titled simply "Rats," which evidently is so popular it's "temporarily out of stock" on Amazon.com -- though you can download it to a Kindle and be reading about the pest-control industry in under a minute.

(Gift wrap is available, for some very special person in your life.)

The Amazon review of "Rats" describes New York's history as "particularly ratty," a characterization that must make the New York City tourism people choke on their $8 bagels.

And the Publisher's Weekly reviewer raves, "You'll feel like you need to wash your hands when you put it down."

Mr. Sullivan traces the rat-per-person myth to a 1909 book about the English rodent problem that determined that in rural areas, there was about one rat per acre of cultivated land. At the time, the acres of such land happened to be equal to the population, so, across the whole country, there was roughly one rat per person. (Two for members of Parliament, and members of the royal family get three but may not use them for hunting.)

I've never seen a rat in Pittsburgh's subway, but they may have found that -- even with the trash receptacles welded shut -- three stops don't furnish enough discarded fast food beyond the Arts Festival and holidays.

Despite our fearful tendency toward rat inflation, a definitive 1949 survey reckoned New York City's rat population at one rat for every 36 people -- coincidentally, also the number of available subway seats.

What else is there to do while you're waiting for a train? Well, maybe write, cast and rehearse a musical. But if you do that, or watch the pan pipe players in their colorful knitted hats, you've missed the animal act below your feet.

Rats.

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