    Sentefiée’ 1: What. was ‘the, Plos’ Pathogens,  Paper about?    Sentence 2: ends. the debate” about the  etiology of the” Black’ Death, and  Uharmbiguously demonstrates that -Y.” pestis  was..the’-causative. “agent “of the epidemic  plague. that devastated -€urope during’ the  Middle Ages".    