Evolutionary history of the angiosperm flora of China
- Nature
- doi:10.1038/nature25485
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Abstract
High
species diversity may result from recent rapid speciation in a ‘cradle’
and/or the gradual accumulation and preservation of species over time
in a ‘museum’1,2.
China harbours nearly 10% of angiosperm species worldwide and has long
been considered as both a museum, owing to the presence of many species
with hypothesized ancient origins3,4,
and a cradle, as many lineages have originated as recent topographic
changes and climatic shifts—such as the formation of the Qinghai–Tibetan
Plateau and the development of the monsoon—provided new habitats that
promoted remarkable radiation5.
However, no detailed phylogenetic study has addressed when and how the major components of the Chinese angiosperm flora assembled to form the present-day vegetation. Here we investigate the spatio-temporal divergence patterns of the Chinese flora using a dated phylogeny of 92% of the angiosperm genera for the region, a nearly complete species-level tree comprising 26,978 species and detailed spatial distribution data. We found that 66% of the angiosperm genera in China did not originate until early in the Miocene epoch (23 million years ago (Mya)).
The flora of eastern China bears a signature of older divergence (mean divergence times of 22.04–25.39 Mya), phylogenetic overdispersion (spatial co-occurrence of distant relatives) and higher phylogenetic diversity. In western China, the flora shows more recent divergence (mean divergence times of 15.29–18.86 Mya), pronounced phylogenetic clustering (co-occurrence of close relatives) and lower phylogenetic diversity. Analyses of species-level phylogenetic diversity using simulated branch lengths yielded results similar to genus-level patterns.
Our analyses indicate that eastern China represents a floristic museum, and western China an evolutionary cradle, for herbaceous genera; eastern China has served as both a museum and a cradle for woody genera. These results identify areas of high species richness and phylogenetic diversity, and provide a foundation on which to build conservation efforts in China.
However, no detailed phylogenetic study has addressed when and how the major components of the Chinese angiosperm flora assembled to form the present-day vegetation. Here we investigate the spatio-temporal divergence patterns of the Chinese flora using a dated phylogeny of 92% of the angiosperm genera for the region, a nearly complete species-level tree comprising 26,978 species and detailed spatial distribution data. We found that 66% of the angiosperm genera in China did not originate until early in the Miocene epoch (23 million years ago (Mya)).
The flora of eastern China bears a signature of older divergence (mean divergence times of 22.04–25.39 Mya), phylogenetic overdispersion (spatial co-occurrence of distant relatives) and higher phylogenetic diversity. In western China, the flora shows more recent divergence (mean divergence times of 15.29–18.86 Mya), pronounced phylogenetic clustering (co-occurrence of close relatives) and lower phylogenetic diversity. Analyses of species-level phylogenetic diversity using simulated branch lengths yielded results similar to genus-level patterns.
Our analyses indicate that eastern China represents a floristic museum, and western China an evolutionary cradle, for herbaceous genera; eastern China has served as both a museum and a cradle for woody genera. These results identify areas of high species richness and phylogenetic diversity, and provide a foundation on which to build conservation efforts in China.
- 1.McKenna, D. D. & Farrell, B. D. Tropical forests are both evolutionary cradles and museums of leaf beetle diversity. Proc. Natl Acad. Sci. USA 103, 10947–10951 (2006)
- 2.Moreau, C. S. & Bell, C. D. Testing the museum versus cradle tropical biological diversity hypothesis: phylogeny, diversification, and ancestral biogeographic range evolution of the ants. Evolution 67, 2240–2257 (2013)
- 3.Blackmore, S., Hong, D.-Y., Raven, P. H. & Wortley, A. H. in Plants of China: A Companion to the Flora of China (eds Hong, D.-Y. & Blackmore, S.) 1–6 (Science Press, 2013)
- 4.Sun, G., Dilcher, D. L., Zheng, S.-L. & Zhou, Z.-K. In search of the first flower: a Jurassic angiosperm, Archaefructus, from northeast China. Science 282, 1692–1695 (1998)
- 5.Wen, J., Zhang, J.-Q., Nie, Z.-L., Zhong, Y. & Sun, H. Evolutionary diversifications of plants on the Qinghai–Tibetan Plateau. Front. Genet. 5, 4 (2014)
- 6.Xing, Y.-W. & Ree, R. H. Uplift-driven diversification in the Hengduan Mountains, a temperate biodiversity hotspot. Proc. Natl Acad. Sci. USA 114, E3444–E3451 (2017)
- 7.Klak, C., Reeves, G. & Hedderson, T. Unmatched tempo of evolution in Southern African semi-desert ice plants. Nature 427, 63–65 (2004)
- 8.Mishler, B. D. et al. Phylogenetic measures of biodiversity and neo- and paleo-endemism in Australian Acacia. Nat. Commun. 5, 4473 (2014)
- 9.Richardson, J. E., Pennington, R. T., Pennington, T. D. & Hollingsworth, P. M. Rapid diversification of a species-rich genus of neotropical rain forest trees. Science 293, 2242–2245 (2001)
- 10.Forest, F. et al. Preserving the evolutionary potential of floras in biodiversity hotspots. Nature 445, 757–760 (2007)
- 11.Verboom, G. A. et al. Origin and diversification of the Greater Cape flora: ancient species repository, hot-bed of recent radiation, or both? Mol. Phylogenet. Evol. 51, 44–53 (2009)
- 12.Thornhill, A. H. et al. Continental-scale spatial phylogenetics of Australian angiosperms provides insights into ecology, evolution and conservation. J. Biogeogr. 43, 2085–2098 (2016)
- 13.Donoghue, M. J. A phylogenetic perspective on the distribution of plant diversity. Proc. Natl Acad. Sci. USA 105, 11549–11555 (2008)
- 14.Svenning, J.-C., Eiserhardt, W. L., Normand, S., Ordonez, A. & Sandel, B. The influence of paleoclimate on present-day patterns in biodiversity and ecosystems. Annu. Rev. Ecol. Evol. Syst. 46, 551–572 (2015)
- 15.Wu, Z.-Y., Raven, P. H. & Hong, D.-Y. (eds) Flora of China, Vol. 1–25 (Science Press & Missouri Botanical Garden Press, 1994–2013)
- 16.Qian, H. & Ricklefs, R. E. A comparison of the taxonomic richness of vascular plants in China and the United States. Am. Nat. 154, 160–181 (1999)
- 17.López-Pujol, J., Zhang, F.-M., Sun, H.-Q., Ying, T.-S. & Ge, S. Centres of plant endemism in China: places for survival or for speciation? J. Biogeogr. 38, 1267–1280 (2011)
- 18.Qian, H. Environmental determinants of woody plant diversity at a regional scale in China. PLoS ONE 8, e75832 (2013)
- 19.Wang, Z.-H., Fang, J.-Y., Tang, Z.-Y. & Lin, X. Patterns, determinants and models of woody plant diversity in China. Proc. R. Soc. Lond. B 278, 2122–2132 (2011)
- 20.The Angiosperm Phylogeny Group. An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG IV. Bot. J. Linn. Soc. 181, 1–20 (2016)
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