Richard wondered if I named Elephant Rock after the state park in Missouri. I did not, though it looks pretty great. As does this rock near Port Reyes, California that I found searching for Elephant Rock images. Apparently there are Elephant Rocks all over the world, from Nevada to Canada to Africa to India to New Zealand (just google image search elephant rock if you're curious).
I've also always liked elephants in general--gigantic matriarchal vegetarians with no real predators--but the name was taken from this Upsetters song, which to me really does sound like something elephants would enjoy.