title: Congruent biogeographical disjunctions at a continent-wide scale: Quantifying and clarifying the role of biogeographic barriers in the Australian tropics.
abstract: OBJECTIVE
  To test whether novel and previously hypothesized biogeogaphic barriers in the Australian Tropics represent significant disjunction points or hard barriers, or both, to the distribution of plants.
  
  
  METHODS
  Australian tropics: Australian Monsoon Tropics and Australian Wet Tropics.
  
  
  METHODS
  The presence or absence of 6,861 plant species was scored across 13 putative biogeographic barriers in the Australian Tropics, including two that have not previously been recognised. Randomizations of these data were used to test whether more species showed disjunctions (gaps in distribution) or likely barriers (range limits) at these points than expected by chance.
  
  
  RESULTS
  Two novel disjunctions in the Australian Tropics flora are identified in addition to eleven putative barriers previously recognized for animals. Of these, eleven disjunction points (all within the Australian Monsoon Tropics) were found to correspond to range-ending barriers to a significant number of species, while neither of the two disjunctions found within the Australian Wet Tropics limited a significant number of species' ranges.
  
  
  CONCLUSIONS
  Biogeographic barriers present significant distributional limits to native plant species in the Australian Monsoon Tropics but not in the Australian Wet Tropics.
authors.affiliation: School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Robert D
authors.identifier: http://orcid.org/0000-0002-4993-2453
authors.initials: RD
authors.lastname: Edwards
authors.affiliation: Research School of Biology, The Australian National University, Acton, Australian Capital Territory, Australia.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Crisp
authors.affiliation: Department of Econometrics and Business Statistics, Monash University, Clayton, Victoria, Australia.
authors.forename: Dianne H
authors.initials: DH
authors.lastname: Cook
authors.affiliation: School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Lyn G
authors.initials: LG
authors.lastname: Cook
mesh_terms: D000818:Animals; D001315:Australia; D044822:Biodiversity; D005075:Biological Evolution; D017753:Ecosystem; D049810:Genetic Speciation; D008954:Models, Biological; D058974:Phylogeography; D010944:Plants / Q000145:classification / Q000235:genetics; D014329:Tropical Climate