Palaeogeographic, climatic and tectonic change in southeastern Australia: the Late Neogene evolution of the Murray Basin

The lasting biological signature of Pliocene tectonics: Reviewing the re‐routing of Australia's largest river drainage system

“…This system is more than 3,300 km in length, and drains more than 1 million square kilometres (14%) of the Australian mainland. As Australia represents a relatively inactive tectonic setting, scientists have often considered its river drainages to have relatively ancient, stable histories (Unmack, ; see McLaren et al, ), and this inactivity is perhaps reflected by comparatively low freshwater fish diversity (McDowall, ; Unmack, ). However, the findings of recent geological (Holdgate, Wallace, Gallagher, Wagstaff, & Moore, ; McLaren et al, ; McLaren, Wallace, & Reynolds, ) and genetic analyses (see below) lead us (and others) to question this assumption of stability.…”

“…As Australia represents a relatively inactive tectonic setting, scientists have often considered its river drainages to have relatively ancient, stable histories (Unmack, ; see McLaren et al, ), and this inactivity is perhaps reflected by comparatively low freshwater fish diversity (McDowall, ; Unmack, ). However, the findings of recent geological (Holdgate, Wallace, Gallagher, Wagstaff, & Moore, ; McLaren et al, ; McLaren, Wallace, & Reynolds, ) and genetic analyses (see below) lead us (and others) to question this assumption of stability. In particular, McLaren et al () proposed an ancestral (Miocene‐Pliocene) southward course of the MDB drainage through the Douglas Depression (Figures and a), a hypothesis conflicting with previous geological reconstructions that had inferred long‐term stability of drainage geometry (e.g.…”

“…Summary topographic (a) and drainage evolution (b) maps of the middle‐lower Murray‐Darling Basin (locations in Figure ), showing the order of events (in legend in b) between Miocene and present that affected the drainage geometry (after Singleton et al, ; Stephenson, ; McLaren et al, , ) [Colour figure can be viewed at wileyonlinelibrary.com]…”

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“…For example, fossil insect and pollen analyses from a small upland paleolake in southeastern Australia indicate that high annual and summer rainfall persisted there until at least 1.5 Ma (Sniderman et al, 2009(Sniderman et al, , 2013, which is inconsistent with the modern climate and vegetation patterns. Drying of a megalake in what is now the semiarid interior of southeastern Australia did not occur until the early Pleistocene (1.5-1.4 Ma; McLaren and Wallace, 2010;McLaren et al, 2011McLaren et al, , 2012McLaren et al, , 2014. In central Australia, there is evidence that the final phase of aridification, marked by the presence of active dune fields, did not initiate until ~1 Ma (Fujioka and Chappell, 2010).…”

Molecular evidence for mid-Pleistocene divergence of populations of three freshwater amphipod species (Talitroidea : Chiltoniidae) on Kangaroo Island, South Australia, with a new spring-associated genus and species

“…The relatively recent divergence of the Kangaroo Island lineage (of less than 0.5 million years ago: Fig. 5) may indicate that the island was colonised by descendents of A. subtenuis inhabiting the Murray Basin, after the draining of Lake Bungunnia and the forming of the lower Murray River, which happened sometime after 0.7 million years ago (Stephenson 1986;McLaren et al 2011).…”