The Cape flora of South Africa grows in a continental area with many diverse and endemic species1,2,3,4. We need to understand the evolutionary origins and ages of such ‘hotspots’ to conserve them effectively5. In volcanic islands the timing of diversification can be precisely measured with potassium–argon dating. In contrast, the history of these continental species is based upon an incomplete fossil record and relatively imprecise isotopic palaeotemperature signatures. Here we use molecular phylogenetics and precise dating of two island species within the same clade as the continental taxa to show recent speciation in a species-rich genus characteristic of the Cape flora. The results indicate that diversification began approximately 7–8 Myr ago, coincident with extensive aridification caused by changes in ocean currents. The recent origin of endemic species diversity in the Cape flora shows that large continental bursts of speciation can occur rapidly over timescales comparable to those previously associated with oceanic island radiations6,7.
Subscribe to Journal
Get full journal access for 1 year
only $3.90 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Good, R. The Geography of Flowering Plants Ch. 10 190–191 (Longman, London, 1974).
Goldblatt, P. An analysis of the flora of southern Africa: its characteristics, relationships and origins. Ann. Missouri Bot. Gard. 65, 369–436 (1978).
Takhtajan, A. Floristic Regions of the World Ch. 4 263–267 (Univ. California Press, Berkeley, 1986).
Linder, H. P., Meadows, M. E. & Cowling, R. M. in The Ecology of Fynbos: Nutrients, Fire and Diversity (ed. Cowling, R. M.) 113–134 (Oxford Univ. Press, Cape Town, 1992).
Myers, N., Mittermeier, R. A., Mittermeier, C. G., da Fonseca, G. A. B. & Kent, J. Biodiversity hotspots for conservation priorities. Nature 403, 853–858 (2000).
Baldwin, B. G. & Robichaux, R. H. in Hawaiian Biogeography: Evolution on a Hotspot Archipelago (eds Wagner, W. L. & Funk, V. A.) 257–287 (Smithsonian Institution Press, Washington DC, 1995).
Givnish, T. J., Sytsma, K. J., Smith, J. F. & Hahn, W. J. in Hawaiian Biogeography: Evolution on a Hotspot Archipelago (eds Wagner, W. L. & Funk, V. A.) 288–337 (Smithsonian Institution Press, Washington DC, 1995).
Cronk, Q. C. B. The Endemic Flora of St Helena 23 (Anthony Nelson, Oswestry, 2000).
Axelrod, D. I. & Raven, P. H. in Biology and Ecology of Southern Africa (ed. Werger, M. J. A.) 77–130 (Junk, The Hague, 1978).
Coetzee, J. A. in Antarctic Glacial History and World Palaeoenvironments (ed. Van Zinderen Bakker, E. M.) 115–127 (Balkema, Rotterdam, 1978).
Coetzee, J. A. Intimations on the Tertiary vegetation of southern Africa. Bothalia 14, 345–354 (1983).
Kennet, J. P. Palaeoceanographic and biogeographic evolution of the southern ocean during the Cenozoic, and Cenozoic microfossil datums. Palaeogeogr. Palaeoclimatol. Palaeoecol. 31, 123–152 (1980).
Linder, H. P. & Mann, D. M. The phylogeny and biogeography of Thamnochortus (Restionaceae). Bot. J. Linn. Soc. 128, 319–357 (1998).
Linder, H. P. in Species and Speciation (ed. Vrba, E. S.) 53–57 (Transvaal Museum Monograph 4 Pretoria, 1985).
Johnson, S. D. Pollination, adaptation and speciation models in the Cape flora of South Africa. Taxon 45, 59–66 (1995).
Hodges, S. A. & Arnold, M. L. Columbines: a geographically widespread species flock. Proc. Natl Acad. Sci. USA 92, 5129–5132 (1994).
Wojciechowski, M. F., Sanderson, M. J. & Hu, J.-M. Evidence on the monophyly of Astragalus (Fabaceae) and its major subgroups based on nuclear ribosomal QNA ITS and chloroplast DNA trnL intron data. Syst. Bot. 24, 409–437 (1999).
Richardson, J. E., Fay, M. F., Cronk, Q. C. B., Bowman, D. & Chase, M. W. A molecular analysis of Rhamnaceae using plastid rbcL and trnL-F sequences. Am. J. Bot. 87, 1309–1324 (2000).
Swofford, D. L. PAUP*4.0b2: Phylogenetic Analysis Using Parsimony. (Sinauer Associates, Sunderland, Massachusetts, 1998).
Fitch, W. M. Toward defining the course of evolution: minimum change for a specified tree topology. Syst. Zool. 20, 406–416 (1971).
Felsenstein, J. Confidence limits on phylogenies: an approach using the bootstrap. Evolution 39, 783–791 (1985).
Felsenstein, J. Evolutionary trees from DNA-sequences—a maximum likelihood approach. J. Mol. Evol. 17, 368–376 (1981).
Sanderson, M. J. A nonparametric approach to estimating divergence times in the absence of rate constancy. Mol. Biol. Evol. 14, 1218–1232 (1997).
Rambaut, A. & Charleston, M. TreeEdit version 1.0 alpha 4-61 〈http://evolve.zoo.ox.ac.uk/software/TreeEdit/TreeEdit.html〉 (2000).
We are grateful to P. Crane, M. Sanderson and the Tropical Biology Group at the Royal Botanic Garden, Edinburgh, for critical comments and discussion. We thank A. de Bruijn and J. Joseph for technical support. The work was funded by a studentship to J.E.R. from the Royal Botanic Gardens, Kew, which also made possible a four-month visit by F.M.W. to Kew to collect additional data. We also thank collectors of plant material: Y. Mungroo, C. Thébaud, M. van der Bank and R. Cairns-Wicks.
About this article
Cite this article
Richardson, J., Weitz, F., Fay, M. et al. Rapid and recent origin of species richness in the Cape flora of South Africa. Nature 412, 181–183 (2001). https://doi.org/10.1038/35084067
Savanna tree evolutionary ages inform the reconstruction of the paleoenvironment of our hominin ancestors
Scientific Reports (2020)
Opposite trends in the genus Monsonia (Geraniaceae): specialization in the African deserts and range expansions throughout eastern Africa
Scientific Reports (2017)
The biodiversity hotspot as evolutionary hot-bed: spectacular radiation of Erica in the Cape Floristic Region
BMC Evolutionary Biology (2016)