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
To Pimp a Butterfly and the works of Christian theologian Paul Tillich, with McLeod calling "To Pimp a Butterfly" an original example of "existentialist hip hop." Meanwhile, Adam Blum discerned connections between "To Pimp a Butterfly" and the writings of psychoanalysts such as Wilfred Bion, Nicolas Abraham, and Sigmund Freud. In an essay published in "The Lancet Psychiatry", University of Cambridge professors Akeem Sule and Becky Inkster described Lamar as the "street poet of mental health," noting how "To Pimp a Butterfly" (as well as its predecessor, "Good Kid, M.A.A.D City") explore topics such as addiction, anxiety, depression, and resilience. Lamar has offered explanations