But that's not creativity. There's no virtually unlimited variety of types of spiderwebs and there is no virtually unlimited variety of types of damns a beavers build. If there were, we'd know. Yet, all we ever see is pretty much always the same.

While it's impossible to be creative without creating, it's perfectly possible to create without being creative. We call that "copying".

In case of spiders and beavers, they simply have the necessary originals/blueprints "built in".