Cohesive conjunctions and their function in the discourse of the popularization of science: Charles Darwin’s correspondence on evolution and related matters

Written correspondence has always constituted a specific text genre through which scientific research is both discussed and carried out (see Gotti 2010), especially so in the case of the biologist Charles Darwin, who conducted most of his relations with the scientific community at a distance but remained actively engaged in the debate on evolution. Written correspondence, therefore, lay at the very heart of Darwin’s scientific enterprise (Christiansen 2010). Darwin’s correspondence also presents fertile terrain for an investigation into the popularization of science because his various correspondents constitute a cross section of the wider discourse community (both expert and non-expert) involved in the new science of natural history. In particular, letter-writing is a form of interaction which has always been highly context-sensitive (Nevalainen and Tanskanen 2007) and thus examining correspondence provides ample opportunity to observe many aspects of social-semiotics that are also relevant to the dichotomy between pure and popularized science (e.g. genre and register – see Christiansen 2010). This chapter will investigate the use of conjunctions in Darwin’s correspondence specifically on evolution (taken from that published in edited form as Life and Letters of Charles Darwin (Vols I and II); More Letters of Charles Darwin (Vols I and II), comparing that to fellow natural historians (approx. 310,000 words) with that to non-experts (approx. 24,500 words) in which his scientific ideas are “popularized”. Conjunctions are important because they play a fundamental role in the cohesion of texts (Halliday and Hasan 1976) providing overt links between clauses and sentences without being a constituent of them (Chris- tiansen 2011) and thus are pivotal in the way that arguments are presented and the way that the ideational content of different clauses are woven together into a coherent discourse. Notwithstanding their centrality, little research has been done into types of conjunctions from the perspective of their cohesive function (additive, adversative etc.; internal, external etc – see Halliday and Hasan 1976) and their contrasting uses in scientific and popularized scientific discourses.