Design Challenge: A World Without Spiders
This post is rated PG for mild Dungeons and Dragons Fourth Edition content. Reader discretion is advised.

Myself and several members of my gaming group suffer from varying forms of aversion to insects and arachnids. In my case, at least, it's bad enough that I have to avoid pages in books that contain pictures of the creeps; I can't even look at a picture without freaking. There, stage set.

I'd like to remove spiders entirely from my next game setting, but it's one thing to arbitrarily say "there's no such thing as spiders"; it's another to have their absence make sense. Spiders fill an interesting ecological niche in the real world; they're predators that prey on scavengers, they don't have any real predators of their own, and they can co-exist with humanity (if the humans can stand them). I can't fully grasp the impact that the simple absence of spiders would have from the world, and while there are other predators of small bugs (like bats), they don't fit quite the same profile.

Compounding this problem is that I've been considering setting my next game in D&D 4th Edition, specifically using the stock setting material... and there's a whole evil goddess and her pet race that's devoted to spiders. Tossing all of that out and distributing her domains among other evil gods is an option, but it seems like the most drastic approach. I'm wondering if there's a better way.

I'm currently toying with the idea of making Lolth the "Demon Queen of Bats" instead; bats do fill a similar niche, they're equally stealthy and love the underground, giant bats can be used as mounts, and heck, demons have bat wings! Seems like a good fit to me.

What I want to hear from you folks is - how would you remove spiders from a game world? What would replace them? What CAN replace them? Any other ideas you might have would be much appreciated.