The image shows a view of a single human brown hair. It is a tube of constant width, and it is interesting that there is a light line across the entirety of the hair. It is notable how incredibly thin the hair is, even upon considerable magnification.

The sample was obtained from my head while I was at the California Institute of Technology at 3:20 pm on 5/27/19. I obtained it by rustling my hand through my hair until a hair detached. (Note to Caltech Bi1 TA’s: I am omitting a picture of my hair (where the sample was obtained) for privacy reasons.)
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