Armand Marie Leroi describes a specimen in the Vrolik museum labelled as 'acardia amorphus', “a skin-covered sphere with nothing to hint at the child it almost became except for a small umbilical cord, a bit of intestine, and the rudiments of a vertebral column.”
It was a startling thing to read because until then, I did not know that human development could go so awry -- that I could've gone so awry. To think, that I could've been a ball.
I felt the compulsion to see concrete evidence of this -- surely Armand was exaggerating? But this was back in 2008ish, when googling such a thing gave me unsatisfying, less sphereical variants (actually, it still does). But I was lucky and resourceful: I found someone's flickr album of their visit to the Vrolik Museum, and flipping through their comprehensive-enough pictures of the display cases, I spotted it. It was rather unassuming, but he was not exaggering. Its roundness was unmistakeable. I've saved it -- now posted here to satisfy your curiosity (it is on the right, bottom-middle).
Six years later, I still somehow found it compelling enough that, when on a trip to Paris, I took a detour to Amsterdam for less than 24 hours, just to see it in person.
And more than a decade later, I came across The Seeming Paradox of Mechanizing Creativity", in Metamagical Themas (Hofstadter) where he talks about 'sphexishness', or a rough gauge of complexity by how good at 'rut-breaking' it is. It gave me another way to help express my fascination with acardia amorphus -- I could've been so sphexish.