How the Snake Lost Its Legs fly embryo. His books on evolutionary developmental biology (evo-devo) include "Imaginal Discs: The Genetic and Cellular Logic of Pattern Formation" (2002), "Quirks of Human Anatomy: An Evo-Devo Look at the Human Body" (2009), and "Deep Homology? Uncanny Similarities of Humans and Flies Uncovered by Evo-Devo" (2017). In Held's view, "Quirks", "Snake", and "Deep Homology" form a trilogy on evo-devo. "How the Snake Lost Its Legs" is ostensibly organised into six chapters, but in effect into three parts. The first chapter serves as an introduction and overview. The next four chapters provide what Held calls "the meatier aspects of evo-devo" with
How Many Licks? and a bling accessary". Lil' Kim and Sisqó also exchange pick-up lines during the song. The chorus refers to the advertising slogan for Tootsie Pops ("How many licks does it takes to get to the Tootsie Roll centre of a Tootsie Pop?"), and ties sexuality to consumerism according to media studies professor Scott Wilson. For the track's remix, Lil' Kim associates her rapping abilities with oral sex: "Ya neva seen this stroke of genius / [I] put tha cleanest, meanest lips on ya penis!" She is also noted to popularize the word "gangstress" which she had previously used in "Spend