Despite what Ed Brayton may claim, Michael Egnor is right. The Design Inference--make that the design inference--is all over science. It's simple: you take a something in nature, figure out how it works by imagining and recreating how it's put together, and presto! Reverse engineering, the design inference.
Let's see how geologists use reverse engineering to demonstrate how volcanoes are designed.
This is a real volcano. It has hot, steaming red stuff coming out of the top. That's lava. What's lava made of? Where does it come from? What is it for? To find out, geologists employ reverse engineering.
These are geologists reverse engineering a volcano. As you can see, their work proves that when an intelligent agent, or designer, combines vinegar, red food coloring, and baking soda in a conical papier-mâché structure, lava boils over the top. (This is known as the Timmy-Hortensia theorem, after its original inventors, or discoverers.)
Since it takes a human designer to reverse engineer a volcano, obviously a volcano is designed. Q.E.D.