Page - 57 - in JRFM - Journal Religion Film Media, Volume 03/02

Emulating Science | 57www.jrfm.eu 2017, 3/2, 53–64 inspired by the work of geologist Charles Lyell, darwin wanted to argue against natural theology: the different finches in the Galápagos Islands had not been created one by one but were all descendants of an original finch. Darwin argued that, through a long process of adaptation across successive genera- tions, the birds had developed different beaks that were better adapted to each environment: heavier beaks were able to break husks or larger seeds; pointed beaks could better pierce fruit, and so on.11 In order to reason that different species were not the product of divine creation but the result of natural selec- tion, Darwin opted for a very traditional rhetorical figure of speech: he created a visual polyptoton. “Polyptoton” is one of the major reasoning strategies listed in Aristotle’s Rhetoric, later detailed in his Topics. It is defined as the repetition of the same word, image, pattern, or root as a persuasive device. in a polyptoton, each time a word or image is repeated, it comes in a slightly different form. According to Fahnestock, in scientific visualizations, the goal of a polyptoton is to create a new knowledge by building upon a concept or an idea that is already accepted or known. By creating a sequence of similar birds with small differences, Darwin intended to build his new theory upon what was already accepted: thus, while it is true that species present physical differences, this certainly does not mean they were individually created by God. darwin took the similar patterns to sug- gest that, instead, they all had evolved from one common ancestor. Polyptoton is not the only Darwinist figure of science that Fahnestock has investigated. she argues that in The Expression of the Emotions in Man and Ani- mals (1872), Darwin endorsed antithesis, another figure of speech, when trying to understand the role that emotions and expressions played in evolutionary adaptation. in an illustration contrasting the behavior of two dogs, darwin op- posed different emotions by placing them side by side. The first dog is visually represented as “hostile”: it has raised hair, an elevated head, bared teeth, and the body in an aggressive posture. The second dog is “humble and affection- ate” and represented in a submissive position. instead of walking upright, the body sinks downward. darwin stated that the ability to identify such visual clues was key for natural selection. humans and animals would know, for example, if someone or something approaching them posed a threat. in his own words, the naturalist stated that animal behaviors could be read in terms of “principles of antithesis” that were part of a body language that was “innate or universal”.12 another relevant example of visual rhetorical tools in the service of evolu- tion is the scientific illustration known as the “Evolution of Homo Sapiens”. this parade representing 25 million years of human evolution is one of the most 11 ibid. 12 darwin 1899, Chapter 2.