This paper brings some data to bear on the criticisms, claims, and arguments that Skinner (a) denied or dismissed biological participation in behavior, (b) addressed it only late in his career or more often later than earlier, or (c) addressed it only because of the overwhelming evidence for it or the criticisms that he had overlooked it. For this, we coded Skinner's every primary-source publication for three content categories (i.e., genetics, physiology, and evolution) and for the extent to which he addressed them (i.e., in publication titles, substantively, or in passing). Our findings are that Skinner addressed biological participation in over a third of his publications throughout his career, albeit more often later than earlier. The latter, however, is accounted for by an increase in his base rate of publication and in general conditions and specific events in his career, psychology, and science. The discussion addresses our research methods; the reasons for and refutations of the criticisms, claims, and arguments; and their sources. (Contains 1 figure and 1 table.)