Fig. 7From: Phylogenetic analysis of human Chlamydia pneumoniae strains reveals a distinct Australian indigenous clade that predates European exploration of the continentEvolutionary hypothesis model describing two alternate hypotheses for the characteristic deep-branching of the Australian indigenous strains SH511 and 1979. In hypothesis A, Australian indigenous strains evolved from a separate zoonotic (or intermediate) transmission event, and continued to evolve in isolation from non-indigenous human C. pneumoniae strains. In hypothesis B, all human C. pneumoniae strains disseminated from a single zoonotic (or intermediate) transmission event and evolved separately in response to differing ecological functionsBack to article page