It's not because this new game, Appaloosa's Jaws Unleashed, is particularly terrific. On the contrary, it's riddled with gameplay flaws (more on this later). But after a couple of hours of severing limbs, overturning boats and roaming the briny deep as nature's finest killing machine, I've had an epiphany: It is unusually fun to experience life as another species. Why don't more games do this?

After all, video games have the unique ability to put you in someone else's shoes. But they usually just port you into the experience of another human: a soldier, an adventurer, a woman with improbable proportions and even less-probable battlewear.

Sure, you get to be someone else; but you rarely get to be something else. When games do have you play as an animal, the animals are pretty humanoid. (In the recent, impossibly dull game of Over the Hedge, the raccoon uses golf clubs to fire charged-up bolts at enemies, which really isn't much different from being a level-12 mage in World of Warcraft.)

In contrast, the idea of being an animal -- with genuinely animal-like movement, skills and behavior -- is really compelling. Jaws Unleashed tries more or less to stick to sharklike movement: You slide through the ocean with sinuous grace, and have to keep moving and feeding to stay alive. Like a real shark, you can't back up, so you wind up inadvertently stumbling upon the ominous techniques that sharks use: You circle your prey until you discover the perfect angle of attack.

The fact that teeth are your primary weapon gives combat an entirely different psychological flavor than, say, Halo. Military experts have long known there's an enormous difference between attacking someone with a gun from far away versus a close-quarters attack, like a bayonet. There's something erotically charged -- something queasily sensual -- about close-quarters attacks, which is why movie psychos always come at their victims with a knife instead of a machine gun.

Jaws Unleashed plays this to maximum effect: When you've got someone in your mouth, you wiggle the left joystick to "play" with them, thrashing them to and fro until body parts fly off. I found it both campily fun and totally unsettling.

Even better than the attacks, though, was the sheer fun of exploring the underwater world. The visuals are so lovely that merely cruising around can be more fun than engaging in the often-daft "missions." Appaloosa pioneered this sort of play with its previous Ecco the Dolphin title, and as it turns out, an animal game neatly reworks the "sandbox" conceit from Grand Theft Auto.

Hell, I'd play a shark game that dispensed with the dorky plot of Jaws Unleashed -- an evil corporation, a hidden plot, whatever -- and just let me spend hours traversing the ocean. It's the most unexplored place on earth, infinitely weirder than even outer space.

Now, before you rush out to buy Jaws Unleashed, I'm compelled to note that it suffers from some excruciating design flaws. The camera angle is almost unbearable -- it boxes you into corners and unpredictably flips into an "above the water" shot when you get near the surface, making combat situations insufferable.

It also has many stupidly un-sharklike elements. Some missions require you to jump out of the water and wriggle onto land; the game also gives you a "nose smash" attack, despite the fact that sharks' noses are tender sensing devices that are easily injured.

Mind you, I'm not suggesting that an animal sim be 100 percent faithful. But imagine the fun -- to say nothing of educational possibilities -- that could be had from letting us become various critters. How about being a sea gull or hawk, zooming vertiginously around the wilderness or cityscapes? Or what about turning into a monkey swinging from vine to vine? Or a cat, with its incredible balance and totally alien sensing abilities? This is just the sort of thing we need to break gaming out of its increasingly stale platform-jumping, run-and-gun conventions.

Interestingly, there's some indication that game designers are keen for this. Last fall's Geist had you "possess" other creatures in the game, allowing you to temporarily become a dog. The recent Paradise lets you partly -- if boringly -- play as a tiger. Closer yet, the "feral" abilities of your human character in Far Cry gave you animal-like enhanced perceptions that were a total blast.

It half made me wish they had simply turned you into an animal and been done with it. Inside every human there's a wildness just waiting to get out.