Let's not dwell on why I was looking up the word callipygian,
or, for that matter, why I checked the Google books ngram graph for it.
Let us instead wonder, who, or maybe what, a century and change before Minaj, before Kardashian, even before Mix-a-Lot, inspired such intense, short-lived, and concentrated use of the word callipygian in 1818 and 1835. The ngram only goes up to 2008 so we may well have once again achieved peak booty, though I doubt it.
Were there just two books published in 1818 and 1835 that were truly, madly, deeply bum obsessed, or were those years periods of bloom and ferment in the study and discussion of well-formed bottoms across a range of media? Surely an historian in dire need of a dissertation topic can help us out here?
Statisticians with sober, reasonable, non-ass-related explanations for the shape of this graph are kindly asked to butt out.