Species diversity can drive speciation


A fundamental question in evolutionary ecology and conservation biology is: why do some areas contain greater species diversity than others? Island biogeographic theory has identified the roles of immigration and extinction in relation to area size and proximity to source areas1,2, and the role of speciation is also recognized as an important factor3,4,5,6. However, one as yet unexplored possibility is that species diversity itself might help to promote speciation, and indeed the central tenets of island biogeographic theory support such a prediction. Here we use data for plants and arthropods of the volcanic archipelagos of the Canary and Hawaiian Islands to address whether there is a positive relationship between species diversity and rate of diversification. Our index of diversification for each island is the proportion of species that are endemic, and we test our prediction that this increases with increasing species number. We show that even after controlling for several important physical features of islands, diversification is strongly related to species number.

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Figure 1: Origin of island endemism.
Figure 2: Elimination of island endemism.
Figure 3: Bivariate plots for the relationship between diversification and species richness.


  1. 1

    MacArthur, R. H. & Wilson, E. O. An equilibrium theory of insular zoogeography. Evolution 17, 373–387 (1963)

    Article  Google Scholar 

  2. 2

    MacArthur, R. H. & Wilson, E. O. The Theory of Island Biogeography (Princeton Univ. Press, Princeton, 1967)

    Google Scholar 

  3. 3

    Gillespie, R. Community assembly through adaptive radiation in Hawaiian spiders. Science 303, 356–359 (2004)

    ADS  CAS  Article  Google Scholar 

  4. 4

    Hubbell, S. P. The Unified Neutral Theory of Biodiversity and Biogeography (Princeton Univ. Press, Princeton, 2001)

    Google Scholar 

  5. 5

    Losos, J. B. & Schluter, D. Analysis of an evolutionary species–area relationship. Nature 408, 847–850 (2000)

    ADS  CAS  Article  Google Scholar 

  6. 6

    Heaney, L. R. Dynamic disequilibrium: a long-term, large-scale perspective on the equilibrium model of island biogeography. Global Ecol. Biogeogr. 9, 59–74 (2000)

    Article  Google Scholar 

  7. 7

    Rosenzweig, M. L. Species Diversity in Time and Space (Cambridge Univ. Press, Cambridge, 1995)

    Google Scholar 

  8. 8

    Tokeshi, M. Species Coexistence: Ecological and Evolutionary Perspectives (Blackwell, Oxford, 1999)

    Google Scholar 

  9. 9

    Carson, H. L. & Clague, D. A. in Hawaiian Biogeography: Evolution on a Hotspot Archipelago (eds Wagner, W. L. & Funk, V. A.) 14–29 (Smithsonian Institution Press, Washington DC, 1995)

    Google Scholar 

  10. 10

    Price, J. P. & Elliott-Fisk, D. L. Topographic history of the Maui Nui complex, Hawai'i, and its implications for biogeography. Pacif. Sci. 58, 27–45 (2004)

    Article  Google Scholar 

  11. 11

    Price, J. P. Floristic biogeography of the Hawaiian Islands: influences of area, environment and paleogeography. J. Biogeogr. 31, 487–500 (2004)

    Article  Google Scholar 

  12. 12

    Acebes Ginovés, J. R., et al. in Lista de Especies Silvestres de Canarias (Hongos, Plantas y Animales Terrestres) (eds Izquierdo, I., Martín, J. L., Zurita, N. & Arechavaleta, M.), 2nd edn (Consejería de Política Territorial y Medio Ambiente Gobierno de Canarias, La Laguna, Tenerife, in the press)

  13. 13

    Oromí, P. & Báez, M. in Lista de Especies Silvestres de Canarias (Hongos, Plantas y Animales Terrestres) (eds Izquierdo, I., Martín, J. L., Zurita, N. & Arechavaleta, M.), 2nd edn (Consejería de Política Territorial y Medio Ambiente Gobierno de Canarias, La Laguna, Tenerife, in the press)

  14. 14

    Nishida, G. M. Bishop Museum—Hawaiian arthropod checklist. 〈http://www2.bishopmuseum.org/HBS/checklist/query.asp?grp=Arthropod〉 (2002).

  15. 15

    Roos, M. C., Kessler, P. J. A., Gradstein, S. R. & Baas, R. Species diversity and endemism of five major Malesian Islands: diversity–area relationships. J. Biogeogr. 31, 1893–1908 (2004)

    Article  Google Scholar 

  16. 16

    Hobohm, C. Plant species diversity and endemism on islands and archipelagos, with special reference to the Macaronesian Islands. Flora 195, 9–24 (2000)

    Article  Google Scholar 

  17. 17

    Buckling, A., Kassen, R., Bell, G. & Rainey, P. B. Disturbance and diversity in experimental microcosms. Nature 408, 961–964 (2000)

    ADS  CAS  Article  Google Scholar 

  18. 18

    Kassen, R., Buckling, A., Bell, G. & Rainey, P. B. Diversity peaks at intermediate productivity in a laboratory microcosm. Nature 406, 508–512 (2000)

    ADS  CAS  Article  Google Scholar 

  19. 19

    Rainey, P. B. & Travisano, M. Adaptive radiation in a heterogeneous environment. Nature 394, 69–72 (1998)

    ADS  CAS  Article  Google Scholar 

  20. 20

    Quinn, G. P. & Keough, M. J. Experimental Design and Data Analysis for Biologists (Cambridge Univ. Press, Cambridge, 2002)

    Google Scholar 

  21. 21

    Draper, N. R., Guttman, I. & Lapczak, L. Actual rejection levels in a certain stepwise test. Commun. Statist. A 8, 99–105 (1979)

    Article  Google Scholar 

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We thank W. Sutherland, G. Hewitt, M. Taylor and T. Givnish for constructive comments.

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Correspondence to Brent C. Emerson.

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The authors declare that they have no competing financial interests.

Supplementary information

Supplementary Data

This file contains additional analyses to ensure results were not simply a statistical artefact from non-independence between measures of diversification and species richness. This file also contains Supplementary Table S1. (DOC 58 kb)

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Emerson, B., Kolm, N. Species diversity can drive speciation. Nature 434, 1015–1017 (2005). https://doi.org/10.1038/nature03450

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