One of my young kin posted in effbee recently about the new Godzilla movie and how excited he was about it, sharing a picture from it. In the picture, Godzilla was HUGE. I mean, way bigger than ships and stuff. (Here's a link to the Wikipedia page, where you can see a poster picture, and see it compared to the Golden Gate Bridge.)
Now I know I'm totally the wrong demographic for this, but I have to admit that when I saw the poster I immediately thought: how the heck did it get to be that big and no one noticed?
Here's the thing: big animals need to eat a lot. A LOT.
There are basically three choices for eating a lot: plants. You do the elephant thing, and you eat plants, a lot of plants. Fortunately, there are lots of plants to eat, at least in some places. (And in the sea, there's algae, which grows fast. But, my understanding is that most algae grows only in relatively shallow areas (or is the free floating kind, which I'll count as plankton for now), so you'd think people would notice a giant lizard thing eating algae off the coast of Humboldt County, wouldn't you?
plankton. This works GREAT for the big baleen whales. There's lots of it, which is good because whales need to eat a lot.
The problem for godzilla eating these things is that really, no one would be scared of a giant manatee godzilla thing, because it would be busy eating plants all the time. Yes, hippos are really dangerous, and you shouldn't swim with them, but they're not going to take out big ships very easily. And whales can be, I suppose, really dangerous around small boats, but not against the navy.
And finally, most plant and plankton eaters don't look fierce and scary, right?
That leaves us with an animal that eats largish animals. But there's simply no largish animal for something the size of Godzilla (in that poster) to eat and get enough. Compared to a Godzilla that size, a whale is like me eating a minnow, not an entirely satisfying meal. And it's a whole lot easier to catch and eat a messful of minnows (or other smallish fish) than whales.
It's worth noting that many of the largest predators around these days are actually smaller than most of their prey, no? I mean, Brown Bears are bigger than salmon, but lions are smaller than wildebeasts. You either have to eat a whole lot of smaller stuffs (salmon, say, or plankton), or have a plentiful supply of bigger stuffs that you can somehow eat (wildebeasts for lions). Even so, hunting big stuff seems to work best cooperatively. Otherwise, it's handy to be bigger than what you want to eat. (That's why I should hunt minnows.)
Thus, a Godzilla that would find the TransAmerican Pyramid barely up to its chest is a Godzilla that would have deep unmet dietary needs. No wonder it's pissed off!
Let's just admit that I wasn't nearly as impressed by the movie poster as my young kin.