In which Max examines the history of research on that Burgess oddball, Opabinia regalis, and asks why this problematic fossil is less problematic than it used to be

In which Max considers the history of the expression “Cambrian explosion” and asks whether it’s here to stay

In which Max finally completes his three-part essay on Stephen Jay Gould and punctuated equilibria, and asks why Gould changed his mind about key features of evolution around 1977

In the second part of a three-part “Problematica,” Max examines why the development of punctuated equilibria did so little to upset Gould’s early adaptationist and progressivist ideas about evolution—at least at first

In the first part of a three-part installment of “Problematica,” Max examines what Stephen Jay Gould was up to on the eve of “Punctuated equilibria: an alternative to phyletic gradualism” (1972), and introduces an interpretive puzzle