Why did this happen to my pennine? I went to check on my pasta and found it in a rather odd configuration.

(Originally, all the pasta was standing together; the few loose ones there are because I had picked up the pot, semi-drained it, and set it back down before taking this photo.)
It had cooked fully submerged in boiling water on a gas stove for 5–10 minutes. The heat was on medium.
The pot was closed with a lid, though the lid has small openings to allow for draining. There was water around the base of the pot, indicating that it had boiled over.

All the pasta had been loose and separate when it was dry and I poured it in. After I drained the water, the pasta continued to stand on end, but some light knocking dislodged it.
 A: Well, I have no background of any kind in physics, but having been encouraged in the comments:
I suspect that the boiling over is a good clue. Because this lid has those built-in holes at the side for draining, water tries to escape through there under some pressure. But I expect the small size of the holes means the water creates little vortices like a drain and a pulling force when it's boiling over.
This force would have interacted with the pasta swirling around in the boiling water, and pushed the noodles into a "path of least resistance" by aligning them as a tube with the direction of the holes. But not being enough to lift them, they remained at the bottom of the pot (perhaps as something swirling down a drain remains suspended in the water for longer than you'd expect?).
As for the gluing with starch, it was pretty light, since as we see some fell away with a little jostling. It may just have been partly an effect of their being packed closely enough to stick to each other. But if they did glue a little to the bottom, that's still possible with the above since the pasta comes to a point rather than being a flush cylinder and so water can still get into it while it makes contact with the bottom.
I can think of a caveat to this theory... In the image, you can see that the pasta is not by one of the grooves in the side of the pot. Those grooves are where the holes align when the lid is on properly, which I think it was at the time. So you would probably expect the noodles to be by the groove.
