Here's the thing about the beached monster of Montauk: In all the pictures, its big canine teeth are visible on the bottom of its mouth but not on top. Dogs generally have their biggest canines on top plus a couple of smaller ones on the bottom. You know who has big canines on the bottom? Pigs! See the picture, left top, via the wildlife blogger behind Animal Tourism, who first floated the pig theory. Not only are many domesticated pigs slaughtered throughout the country for delicious pork products, but also there has apparently been a huge boom in the U.S. wild pig population. So it's not a stretch to imagine one washing up in Long Island. If this creature is a pig, it would fit with this email tip we got a few days ago:

The monster is a capibarra, a wild pig/rat from South America, it is considered a delicacy in Brazil. Taste like Chicken! I've had it and its not bad. To prepare it you can drop it boiling water to remove the skin, then roast it.

A foreign pig, eh? That would sure explain this picture of Monty acting like a terrorist (left), courtesy the brand new Montauk Monster mash-up site.

But there's one problem with focusing on the lack of upper teeth, as in the pig theory: The skull as show in the original, more decomposed picture of the monster looks like it has sockets for teeth on the top.

These sockets would be critical not only to the dog theory, but also the raccoon theory, as illustrated in this image from a chat board discussion:

And of course, pigs have some upper teeth, too, so the sockets don't rule out Monty being a pig.

But it's worth noting that monsters and demon hellspawn are known for bad dental hygiene, so there's always that!