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Citation for Study 1083

Citation title: "Contrasting patterns of radiation in African and Australian Restionaceae.".

This study was previously identified under the legacy study ID S987 (Status: Published).

Citation

Linder H., Eldens P., Briggs B., & Elden?s P. 2003. Contrasting patterns of radiation in African and Australian Restionaceae. Evolution, 57.

Authors

• Linder H.
• Eldens P.
• Briggs B.
• Elden?s P.

Abstract

The floras of the mediterranean-climate areas of southern Africa and south-western Australia are remarkably species rich. Since the two areas are at similar latitudes and in similar positions on their respective continents, they have probably had similar Cenozoic climatic histories. Here we test the prediction that the evolution of the species richness in the two areas followed a similar temporal progression, by comparing the rates of lineage accumulation for African and Australian Restionaceae. Restionaceae (Poales) are typical and often dominant elements in the fynbos vegetation of the Cape Floristic Region of Southern Africa and the kwongan vegetation of the South Western Floristic Province of Western Australia. The phylogeny of the family was estimated from combined datasets for rbcL and trnL?F sequences and a large morphological dataset: these datasets are largely congruent. The monophyly of Restionaceae is supported, and a basal division into an African clade (c. 350 species) and an Australian clade (146 species) corroborated. There is also support for a futher subdivision of these two large sister-clades, but the terminal resolution within the African clade is very weak. Fossil pollen records provided a minimum age of the common ancestor of Australian and African Restionaceae as 64?71 Mya, and this date was used to calibrate a molecular clock. Since a molecular clock was rejected by a likelihood ratio test, rate changes between the lineages were smoothed using non-parametric rate smoothing. The rate-corrected ages were used to construct a plot of lineages through time. During the Palaeogene the Australian lineage diversity increased consistent with the predictions of the constant birthrate model, while the African lineage diversity showed a dramatic increase in diversification rate in the Miocene. Incomplete sampling obscures the patterns in the Neogene, but extending the trends to the modern extant diversity suggests that this acceleration in the speciation rate continued in the African clade, while the Australian clade retained a constant diversification rate. The substantial morphological and anatomical similarity between the African and Australian Restionaceae appear to preclude morphological innovations as possible explanations for the inter-continental differences. Most likely these differences are due to the greater geographical extent and ecological variation in temperate Australia than temperate Africa, which might have provided refugia for basal Restionaceae lineages, while the more mountainous terrain of southern Africa might have provided the selective regimes for a more rapid, recent speciation.

About this resource

• Canonical resource URI: http://purl.org/phylo/treebase/phylows/study/TB2:S1083
• Other versions: Nexus NeXML
• Show BibTeX reference

  		@ARTICLE{TreeBASE2Ref16408,
  	 author = {Hans Peter  Linder and P.  Eldens and Barbara G.  Briggs and Pia  Elden?s},
  	 title = {Contrasting patterns of radiation in African and Australian Restionaceae.},
  	 year = {2003},
  	 keywords = {},
  	 doi = {},
  	 url = {},
  	 pmid = {},
  	 journal = {Evolution},
  	 volume = {57},
  	 number = {},
  	 pages = {},
  	 abstract = {The floras of the mediterranean-climate areas of southern Africa and south-western Australia are remarkably species rich. Since the two areas are at similar latitudes and in similar positions on their respective continents, they have probably had similar Cenozoic climatic histories. Here we test the prediction that the evolution of the species richness in the two areas followed a similar temporal progression, by comparing the rates of lineage accumulation for African and Australian Restionaceae. Restionaceae (Poales) are typical and often dominant elements in the fynbos vegetation of the Cape Floristic Region of Southern Africa and the kwongan vegetation of the South Western Floristic Province of Western Australia. The phylogeny of the family was estimated from combined datasets for rbcL and trnL?F sequences and a large morphological dataset: these datasets are largely congruent. The monophyly of Restionaceae is supported, and a basal division into an African clade (c. 350 species) and an Australian clade (146 species) corroborated. There is also support for a futher subdivision of these two large sister-clades, but the terminal resolution within the African clade is very weak. Fossil pollen records provided a minimum age of the common ancestor of Australian and African Restionaceae as 64?71 Mya, and this date was used to calibrate a molecular clock. Since a molecular clock was rejected by a likelihood ratio test, rate changes between the lineages were smoothed using non-parametric rate smoothing. The rate-corrected ages were used to construct a plot of lineages through time. During the Palaeogene the Australian lineage diversity increased consistent with the predictions of the constant birthrate model, while the African lineage diversity showed a dramatic increase in diversification rate in the Miocene. Incomplete sampling obscures the patterns in the Neogene, but extending the trends to the modern extant diversity suggests that this acceleration in the speciation rate continued in the African clade, while the Australian clade retained a constant diversification rate. The substantial morphological and anatomical similarity between the African and Australian Restionaceae appear to preclude morphological innovations as possible explanations for the inter-continental differences. Most likely these differences are due to the greater geographical extent and ecological variation in temperate Australia than temperate Africa, which might have provided refugia for basal Restionaceae lineages, while the more mountainous terrain of southern Africa might have provided the selective regimes for a more rapid, recent speciation.}
  }
  		

• Show RIS reference

  		TY  - JOUR
  ID  - 16408
  AU  - Linder,Hans Peter 
  AU  - Eldens,P. 
  AU  - Briggs,Barbara G. 
  AU  - Elden?s,Pia 
  T1  - Contrasting patterns of radiation in African and Australian Restionaceae.
  PY  - 2003
  KW  - 
  UR  - 
  N2  - The floras of the mediterranean-climate areas of southern Africa and south-western Australia are remarkably species rich. Since the two areas are at similar latitudes and in similar positions on their respective continents, they have probably had similar Cenozoic climatic histories. Here we test the prediction that the evolution of the species richness in the two areas followed a similar temporal progression, by comparing the rates of lineage accumulation for African and Australian Restionaceae. Restionaceae (Poales) are typical and often dominant elements in the fynbos vegetation of the Cape Floristic Region of Southern Africa and the kwongan vegetation of the South Western Floristic Province of Western Australia. The phylogeny of the family was estimated from combined datasets for rbcL and trnL?F sequences and a large morphological dataset: these datasets are largely congruent. The monophyly of Restionaceae is supported, and a basal division into an African clade (c. 350 species) and an Australian clade (146 species) corroborated. There is also support for a futher subdivision of these two large sister-clades, but the terminal resolution within the African clade is very weak. Fossil pollen records provided a minimum age of the common ancestor of Australian and African Restionaceae as 64?71 Mya, and this date was used to calibrate a molecular clock. Since a molecular clock was rejected by a likelihood ratio test, rate changes between the lineages were smoothed using non-parametric rate smoothing. The rate-corrected ages were used to construct a plot of lineages through time. During the Palaeogene the Australian lineage diversity increased consistent with the predictions of the constant birthrate model, while the African lineage diversity showed a dramatic increase in diversification rate in the Miocene. Incomplete sampling obscures the patterns in the Neogene, but extending the trends to the modern extant diversity suggests that this acceleration in the speciation rate continued in the African clade, while the Australian clade retained a constant diversification rate. The substantial morphological and anatomical similarity between the African and Australian Restionaceae appear to preclude morphological innovations as possible explanations for the inter-continental differences. Most likely these differences are due to the greater geographical extent and ecological variation in temperate Australia than temperate Africa, which might have provided refugia for basal Restionaceae lineages, while the more mountainous terrain of southern Africa might have provided the selective regimes for a more rapid, recent speciation.
  L3  - 
  JF  - Evolution
  VL  - 57
  IS  - 
  ER  -