12 - Effective evolutionary time and the latitudinal diversity gradient  pp. 169-180

Effective evolutionary time and the latitudinal diversity gradient

By Len N. Gillman and Shane D. Wright

Image View Previous Chapter Next Chapter



Introduction

The relationship between climate and biodiversity is perhaps the most widely recognized and extensively studied pattern of nature on earth. Attempts to explain this relationship and the attendant latitudinal gradient in diversity began more than 200 years ago (von Humboldt, 1808; Wallace, 1878) and indeed the number of theories that attempt to address this question appears to be accumulating at an ever increasing rate. However, one theory which has received relatively little attention began with the observation by Rensch (1959) that animals living in warmer tropical climates have shorter generation times than those living at higher latitudes. He suggested that because natural selection accumulates change with each generation, shorter generation times found among tropical fauna might increase the pace of natural selection and thereby the pace at which evolution progresses. A faster evolutionary speed in the tropics would therefore lead to the evolution of more species there than at higher latitudes over an equivalent period of time.

Evidence suggesting that mutations can be induced by high temperatures prompted Rohde (1978, 1992) to predict that not only might rates of selection increase with increasing ambient energy towards the tropics, but that rates of mutation may also be greater in lower-latitude climates. It is predicted that the combined effects of faster rates of mutation and faster rates of selection will lead to greater rates of diversification. Over an equivalent period of time, regions experiencing generally faster rates of genetic evolution will therefore generate and accumulate more species and greater species richness than regions where genetic evolution is slower. Fundamental to this hypothesis is the precept that the incumbent diversity of species within communities is not at an equilibrium number set by contemporary environmental conditions. Instead, it suggests that communities continue to accumulate species at rates that depend on climatic variables. This theory is therefore quite different to those, such as the energy-richness or more individuals hypothesis (Hutchinson, 1959; Brown, 1981; Wright, 1983), that suggest that diversity is limited by energetic capacity of the environment and that species origination and extinction are therefore held in balance with climate.

Allen, A. , Gillooly, J. , Savage, V. , & Brown, J. (2006). Kinetic effects of temperature on rates of genetic divergence and speciation. Proceedings of the National Academy of Sciences of the USA, 103, 9130–9135.
Anderson, K. J. , & Jetz, W. (2005). The broad-scale ecology of energy expenditure of endotherms. Ecology Letters, 8, 310–318.
Ashton, K. G. , Tracy, M. C. , & Dequeiroz, A. (2000). Is Bergmann’s rule valid for mammals. The American Naturalist, 156, 390–415.
Bleiweiss, R. (1998). Relative-rate tests and biological causes of molecular evolution in hummingbirds. Molecular Biology and Evolution, 15, 481–491.
Bromham, L. , & Cardillo, M. (2003). Testing the link between the latitudinal gradient in species richness and rates of molecular evolution. Journal of Evolutionary Biology, 16, 200–207.
Bromham, L. , Rambaut, A. , & Harvey, P. H. (1996). Determinants of rate variation in mammalian DNA sequence evolution. Journal of Molecular Evolution, 43, 610–621.
Brook, B. W. , Sodhi, N. S. , & Ng, P. K. L. (2003). Catastrophic extinctions follow deforestation in Singapore. Nature, 424, 420–423.
Brown, J. H. (1981). Two decades of homage to Santa Rosalia: toward a general theory of diversity. American Zoology, 21, 877–888.
Cardillo, M. (1999). Latitude and rates of diversification in birds and butterflies. Proceedings of the Royal Society of London B, 266, 1221–1225.
Clarke, A. , Rothery, P. , & Isaac, N. J. (2010). Scaling of basal metabolic rate with body mass and temperature in mammals. Journal of Animal Ecology, 79, 610–619.
Cooper, N. , & Purvis, A. (2009). What factors shape rates of phenotypic evolution? A comparative study of cranial morphology of four mammalian clades. Journal of Evolutionary Biology, 22, 1024–1035.
Davies, T. , Savolainen, V. , Chase, M. , Moat, J. , & Barraclough, T. (2004). Environmental energy and evolutionary rates in flowering plants. Proceedings of the Royal Society of London B, 271, 2195–2200.
Gillman, L. N. , Keeling, D. J. , Gardner, R. C. , & Wright, S. D. (2010). Faster evolution of highly conserved DNA in tropical plants. Journal of Evolutionary Biology, 23, 1327–1330.
Gillman, L. N. , McCowan, L. , & Wright, S. D. (2012). The tempo of genetic evolution in birds: body mass, population size and climate effects. Journal of Biogeography, 39, 1567–1572.
Gillman, L. N. , Ross, H. A. , Keeling, J. D. , & Wright, S. D. (2009). Latitude, elevation and the tempo of molecular evolution in mammals. Proceedings of the Royal Society of London B, 276, 3353–3359.
Gillooly, J. F. , Allen, A. P. , West, G. B. , & Brown, J. H. (2005). The rate of DNA evolution: effects of body size and temperature on the molecular clock. Proceedings of the National Academy of Sciences of the USA, 102, 140–145.
Goldie, X. , Gillman, L. N. , Crisp, M. , & Wright, S. D. (2010). Evolutionary speed limited by water in arid Australia. Proceedings of the Royal Society of London B, 277, 2645–2653.
Goldie, X. , Lanfear, R. , & Bromham, L. (2011). Diversification and the rate of molecular evolution: no evidence of a link in mammals. BMC Evolutionary Biology, 11, 1471–2148.
Gossmann, T. I. , Keightley, P. D. , & Eyre-Walker, A. (2012). The effect of variation in the effective population size on the rate of adaptive molecular evolution in eukaryotes. Genome Biology and Evolution, 4, 658–667.
Hillebrand, H. (2004). On the generality of the latitudinal diversity gradient. The American Naturalist, 163, 192–211.
Hutchinson, G. E. (1959). Homage to Santa Rosalia or why are there so many kinds of animals? American Naturalist, 93, 145–159.
Lancaster, L. T. (2010). Molecular evolutionary rates predict extinction and speciation in temperate angiosperm lineages. BMC Evolutionary Biology, 10, 162.
Lanfear, R. , Ho, S. Y. W. , Love, D. , & Bromham, L. (2010). Mutation rate is linked to diversification in birds. Proceedings of the National Academy of Sciences of the USA, 107, 20423–20428.
Lanfear, R. , Thomas, J. A. , Welch, J. J. , Brey, T. , & Bromham, L. (2007). Metabolic rate does not calibrate the molecular clock. Proceedings of the National Academy of Sciences of the USA, 104, 15388–15393.
Martin, A. P. , & Palumbi, S. R. (1993). Body size, metabolic rate, generation time, and the molecular clock. Proceedings of the National Academy of Sciences of the USA, 90, 4087–4091.
Mckechnie, A. E. , & Lovegrove, B. G. (2002). Avian facultative hypothermic responses: a review. Condor, 104, 705–724.
Munro, D. , Thomas, D. W. , & Humphries, M. M. (2005). Torpor patterns of hibernating eastern chipmunks Tamias striatus vary in response to the size and fatty acid composition of food hoards. Journal of Animal Ecology, 74, 692–700.
Nabholz, B. , Glemin, S. , & Galtier, N. (2008). Strong variations of mitochondrial mutation rate across mammals – the longevity hypothesis. Molecular Biology and Evolution, 25, 120–130.
Nikolaev, S. I. , Montoya-Burgos, J. I. , Popadin, K. , Parand, L. , & Margulies, E. H. (2007). Life-history traits drive the evolutionary rates of mammalian coding and noncoding genomic elements. Proceedings of the National Academy of Sciences of the USA, 104, 20443–20448.
Nunn, G. , & Stanley, S. (1998). Body size effects and rates of cytochrome b evolution in tube-nosed seabirds. Molecular Biology and Evolution, 15, 1360–1371.
Ohta, T. (1992). The nearly neutral theory of molecular evolution. Annual Review of Ecology and Systematics, 23, 263–286.
Pagel, M. , Venditti, C. , & Meade, A. (2006). Large punctuational contribution of speciation to evolutionary divergence at the molecular level. Science 314, 119–121.
Patterson, B. D. , Meserve, P. L. , & Lang, B. K. (1989). Distribution and abundance of small mammals along an elevational transect in temperate rainforests of Chile. Journal of Mammalogy, 70, 67–78.
Rensch, B. (1959). Evolution Above the Species Level. London: Methuen.
Rohde, K. (1978). Latitudinal gradients in species diversity and their causes. I. A review of the hypotheses explaining the gradients. Biologisches Zentralblatt, 97, 393–403.
Rohde, K. (1992). Latitudinal gradients in species diversity: the search for the primary cause. Oikos, 65, 514–527.
Simpson, G. G. (1953). The Major Features of Evolution. New York: Columbia University Press.
Smith, S. A. , & Donoghue, M. J. (2008). Rates of molecular evolution are linked to life history in flowering plants. Science, 322, 86–89
Stevens, G. C. (1989). The latitudinal gradient in geographical range: how so many species coexist in the tropics.The American Naturalist, 133, 240–256.
Stockwell, C. A. , Hendry, A. P. , & Kinnison, M. T. (2003). Contemporary evolution meets conservation biology. Trends in Ecology & Evolution, 18, 94–101.
Thomas, J. A. , Welch, J. J. , Lanfear, R. , & Bromham, L. (2010). A generation time effect on the rate of molecular evolution in invertebrates. Molecular Biology and Evolution, 27, 1173–1180.
VanValen, L. M. (1973). A new evolutionary law. Evolutionary Theory, 1, 1–30.
Von Humboldt, A. (1808). Ansichten der Natur mit wissenschaftlichen Erlauterungen. Tübingen.
Wallace, A. R. (1878). Tropical Nature and Other Essays. London: Macmillan.
Webster, A. J. , Payne, R. J. H. , & Pagel, M. (2003). Molecular phylogenies link rates of evolution and speciation. Science, 301, 478.
Weir, J. T. , & Schluter, D. (2008). Calibrating the avian molecular clock. Molecular Ecology, 17, 2321–2328.
Welch, J. J. , Bininda-Emonds, O. R. , & Bromham, L. (2008). Correlates of substitution rate variation in mammalian protein-coding sequences. BMC Evolutionary Biology, 8, 1471–2148.
Woolfit, M. , & Bromham, L. (2005). Population size and molecular evolution on islands. Proceedings of the Royal Society of London B, 272, 2277–2282.
Wright, D. H. (1983). Species-energy theory: an extension of species-area theory. Oikos, 41, 496–506.
Wright, S. , Keeling, J. , & Gillman, L. (2006). The road from Santa Rosalia: a faster tempo of evolution in tropical climates. Proceedings of the National Academy of Sciences of the USA, 103, 7718–7722.
Wright, S. D. , Gillman, L. N. , Ross, H. A. , & Keeling, D. J. (2010). Energy and the tempo of evolution in amphibians. Global Ecology and Biogeography, 19, 733–740.
Wright, S. D. , Gillman, L. N. , Ross, H. A. , & Keeling, J. D. (2009). Slower tempo of microevolution in island birds: implications for conservation biology. Evolution, 63, 2276–2287.
Wright, S. D. , Gray, R. D. , & Gardner, R. C. (2003). Energy and the rate of evolution: inferences from plant rDNA substitution rates in the western Pacific. Evolution, 57, 2893–2898.
Wright, S. D. , Ross, H. A. , Keeling, D. J. , McBride, P. , & Gillman, L. N. (2011). Thermal energy and the rate of genetic evolution in marine fishes. Evolutionary Ecology, 25, 525–530.