[This is post #19 in a mini-blog-post series for NaBloPoMo 2015. Jump to the first, previous, or next post.]

Congrats again on finishing your Straws Thingy! (If you had or are having trouble, please let me know.)

During the next week we’ll prod more deeply into a few features of this sculpture’s symmetries, especially those that become apparent during construction.

To begin, a puzzle: all three of these Straws Thingys were built precisely according to the instructions outlined earlier, and yet, they’re not identical arrangements! What differs?

This is not meant to be a trick question: their dissimilarity is clearly visible in this image without zooming in or guessing. And in fact, two of these three are identical. Who’s the odd one out? Are there other ways this difference can manifest?