Evolutionary Ecology

, Volume 27, Issue 1, pp 133–143 | Cite as

Genetic diversity within vertebrate species is greater at lower latitudes

Original Paper


The latitudinal gradient of species diversity is one of the oldest recognized patterns in biology. While the cause of the pattern remains debated, the global signal of greater diversity toward the tropics is widely established. Whether the pattern holds for genetic diversity within species, however, has received much less attention. We examine latitudinal variation of intraspecific genetic diversity by contrasting nucleotide distance within low- and high-latitude animal groups. Using mitochondrial DNA markers across 72 vertebrate species that together span six continents, two oceans, and 129 degrees of latitude, we found significantly greater genetic diversity at low latitudes within mammalian species, and trends consistent with this pattern in reptiles, amphibians, fish, and birds. The signal held even after removing species whose current geographic ranges include areas recently covered by glaciers during the late Pleistocene and which presumably have experienced colonization bottlenecks in high latitudes. Higher genetic diversity within species was found at low latitudes also for genera that do not possess higher species richness toward the tropics. Moreover, examination of a subset of species with sufficient sampling across a broad geographic range revealed that genetic variation demonstrates a typical gradient, with mid-latitude populations intermediate in genetic diversity between high and low latitude ones. These results broaden the pattern of the global latitudinal diversity gradient, to now include variation within species. These results are also concordant with other studies indicating that low latitude populations and species are on different evolutionary trajectories than high latitude ones, and we speculate that higher rates of evolution toward the equator are driving the pattern for genetic diversity within species.


Biogeography Conservation Diversity gradient Glaciation Mitochondrial makers 



We thank Rodolfo Dirzo for valuable discussion and comments on earlier drafts of the manuscript.

Supplementary material

10682_2012_9587_MOESM1_ESM.docx (51 kb)
Supplementary material 1 (DOCX 51 kb)


  1. Adams RI, Hadly EA (2010) High levels of gene flow in the California vole (Microtus californicus) are consistent across spatial scales. West N Am Nat 70:296–311CrossRefGoogle Scholar
  2. Allen AP, Gillooly JF, Savage VM et al (2006) Kinetic effects of temperature on rates of genetic divergence and speciation. Proc Natl Acad Sci 103:9130–9135PubMedCrossRefGoogle Scholar
  3. Antonovics J (2003) Toward community genomics? Ecology 84:598–601CrossRefGoogle Scholar
  4. Avise JC (2000) Phylogeography: the history and formation of species. Harvard University Press, CambridgeGoogle Scholar
  5. Borden WC, Krebs RA (2009) Phylogeography and postglacial dispersal of smallmouth bass (Micropterus dolomieu) into the Great Lakes. Can J Fish Aquat Sci 66:2142–2156CrossRefGoogle Scholar
  6. Bromham L, Cardillo M (2003) Testing the link between the latitudinal gradient in species richness and rates of molecular evolution. J Evol Biol 16:200–207PubMedCrossRefGoogle Scholar
  7. Buckley LB, Davies TJ, Ackerly DD et al (2010) Phylogeny, niche conservatism and the latitudinal diversity gradient in mammals. Proc R Soc Biol Sci Ser B 277:2131–2138CrossRefGoogle Scholar
  8. Chek AA, Austin JD, Lougheed SC (2003) Why is there a tropical-temperate disparity in the genetic diversity and taxonomy of species? Evol Ecol Res 5:69–77Google Scholar
  9. Clark PU, Mix AC (2002) Ice sheets and sea level of the Last Glacial Maximum. Quat Sci Rev 21:1–7CrossRefGoogle Scholar
  10. Colwell RK, Lees DC (2000) The mid-domain effect: geometric constraints on the geography of species richness. Trends Ecol Evol 15:70–76PubMedCrossRefGoogle Scholar
  11. Colwell RK, Rahbek C, Gotelli NJ (2004) The mid-domain effect and species richness patterns: what have we learned so far? Am Nat 163:E1–E23PubMedCrossRefGoogle Scholar
  12. Conroy CJ, Neuwald JL (2008) Phylogeographic study of the California vole, Microtus californicus. J Mammal 89:755–767CrossRefGoogle Scholar
  13. Dirzo R, Raven PH (2003) Global state of biodiversity and loss. Annu Rev Environ Resour 28:137–167CrossRefGoogle Scholar
  14. Eckert CG, Samis KE, Lougheed SC (2008) Genetic variation across species’ geographical ranges: the central-marginal hypothesis and beyond. Mol Ecol 17:1170–1188PubMedCrossRefGoogle Scholar
  15. Eo SH, Wares JP, Carroll JP (2008) Population divergence in plant species reflects latitudinal biodiversity gradients. Biol Lett 4:382–384PubMedCrossRefGoogle Scholar
  16. Food and Agriculture Organization (2010) The state of the world’s plant genetic resources for food and agriculture. United Nations, RomeGoogle Scholar
  17. Freestone AL, Osman RW, Ruiz GM et al (2011) Stronger predation in the tropics shapes species richness patterns in marine communities. Ecology 92:983–993PubMedCrossRefGoogle Scholar
  18. Gillman LN, Keeling DJ, Ross HA et al (2009) Latitude, elevation and the tempo of molecular evolution in mammals. Proc R Soc Biol Sci Ser B 276:3353–3359CrossRefGoogle Scholar
  19. Gillooly JF, Allen AP, West GB et al (2005) The rate of DNA evolution: effects of body size and temperature on the molecular clock. Proc Natl Acad Sci 102:140–145PubMedCrossRefGoogle Scholar
  20. Hawkins BA (2001) Ecology’s oldest pattern? Trends Ecol Evol 16:470CrossRefGoogle Scholar
  21. Hewitt GM (2000) The genetic legacy of the Quaternary ice ages. Nature 45:907–913CrossRefGoogle Scholar
  22. Hewitt GM (2004) Genetic consequences of climatic oscillations in the Quaternary. Philos Trans R Soc Lond B Biol Sci 359:183–195PubMedCrossRefGoogle Scholar
  23. Hillebrand H (2004) On the generality of the latitudinal diversity gradient. Am Nat 163:192–211PubMedCrossRefGoogle Scholar
  24. Hughes AL, Hughes MA (2007) Coding sequence polymorphism in avian mitochondrial genomes reflects population histories. Mol Ecol 16:1369–1376PubMedCrossRefGoogle Scholar
  25. Hughes JB, Daily GC, Ehrlich PR (1997) Population diversity: its extent and extinction. Science 278:689–692PubMedCrossRefGoogle Scholar
  26. Hulton NRJ, Purves RS, Mcculloch RD et al (2002) The Last Glacial Maximum and deglaciation in southern South America. Quat Sci Rev 21:233–241CrossRefGoogle Scholar
  27. Jablonski D, Roy K, Valentine JW (2006) Out of the tropics: evolutionary dynamics of the latitudinal diversity gradient. Science 3124:102–106CrossRefGoogle Scholar
  28. Johnson MTJ, Stinchcombe JR (2007) An emerging synthesis between community ecology and evolutionary biology. Trends Ecol Evol 22:250–257PubMedCrossRefGoogle Scholar
  29. Kimura M (1980) A simple method for estimating evolutionary rates of base substitutions through comparative studies of nucleotide sequences. J Mol Evol 16:111–120PubMedCrossRefGoogle Scholar
  30. Kimura M, Clegg SM, Lovette IJ et al (2002) Phylogeographical approaches to assessing demographic connectivity between breeding and overwintering regions in a Nearctic-Neotropical warbler (Wilsonia pusilla). Mol Ecol 11:1605–1616PubMedCrossRefGoogle Scholar
  31. Lessa EP, D’elia G, Pardinas UFJ (2010) Genetic footprints of late Quaternary climate change in the diversity of Patagonian-Fueguian rodents. Mol Ecol 19:3031–3037PubMedCrossRefGoogle Scholar
  32. Martin PR, Mckay JK (2004) Latitudinal variation in genetic divergence of populations and the potential for future speciation. Evolution 58:938–945PubMedGoogle Scholar
  33. Mclachlan JS, Hellmann JJ, Schwartz MW (2007) A framework for debate of assisted migration in an era of climate change. Conserv Biol 21:297–302PubMedCrossRefGoogle Scholar
  34. Miller MJ, Bermingham E, Klicka J et al (2010) Neotropical birds show a humped distribution of within-population genetic diversity along a latitudinal transect. Ecol Lett 13:576–586PubMedCrossRefGoogle Scholar
  35. Mittelbach GG, Schemske DW, Cornell HV et al (2007) Evolution and the latitudinal diversity gradient: speciation, extinction and biogeography. Ecol Lett 10:315–331PubMedCrossRefGoogle Scholar
  36. Myers N, Mittermeier RA, Mittermeier CG et al (2000) Biodiversity hotspots for conservation priorities. Nature 403:853–858PubMedCrossRefGoogle Scholar
  37. Nei M (1987) Molecular evolutionary genetics. Columbia University Press, New YorkGoogle Scholar
  38. Nevo E (2001) Genetic diversity. In: Levin SA (ed) Encyclopedia of Biodiversity, 3rd edn. Academic Press, San Diego, pp 195–213CrossRefGoogle Scholar
  39. Palmer MW (1994) Variation in species richness: towards a unification of hypotheses. Folia Geobot Phytotx 29:511–530Google Scholar
  40. Pianka ER (1966) Latitudinal gradients in species diversity: a review of concepts. Am Nat 100:33–46CrossRefGoogle Scholar
  41. Powell MG (2007) Latitudinal diversity gradients for brachiopod genera during late Palaeozoic time: links between climate, biogeography and evolutionary rates. Glob Ecol Biogeogr 16:519–528CrossRefGoogle Scholar
  42. Rohde K (1992) Latitudinal gradients in species diversity: the search for primary cause. Oikos 65:514–527CrossRefGoogle Scholar
  43. Rosenzweig ML (1995) Species diversity in space and time. Cambridge University Press, CambridgeCrossRefGoogle Scholar
  44. Stehli FG, Douglas RG, Newell ND (1969) Generation and maintenance of gradients in taxonomic diversity. Science 164:947–949PubMedCrossRefGoogle Scholar
  45. Stevens RD (2004) Untangling latitudinal richness gradients at higher taxonomic levels: familial perspectives on the diversity of New World bat communities. J Biogeogr 31:665–674CrossRefGoogle Scholar
  46. Tamura K, Dudley J, Nei M et al (2007) MEGA4: molecular evolutionary genetics analysis (MEGA) software version 4.0. Mol Biol Evol 24:1596–1599PubMedCrossRefGoogle Scholar
  47. Vellend M (2005) Species diversity and genetic diversity: parallel processes and correlated patterns. Am Nat 166:199–215PubMedCrossRefGoogle Scholar
  48. Weir JT, Schluter D (2008) Calibrating the avian molecular clock. Mol Ecol 17:2321–2328PubMedCrossRefGoogle Scholar
  49. Wiens JJ, Graham CH, Moen DS et al (2006) Evolutionary and ecological causes of the latitudinal diversity gradient in hylid frogs: Treefrog trees unearth the roots of high tropical diversity. Am Nat 168:579–596PubMedCrossRefGoogle Scholar
  50. Willig MR, Kaufman DM, Stevens RD et al (2003) Latitudinal gradients of biodiversity: pattern, process, scale, and synthesis. Annu Rev Ecol Evol Syst 34:273–309CrossRefGoogle Scholar
  51. Wright SD, Keeling J, Gillman L (2006) The road from Santa Rosalia: a faster tempo of evolution in tropical climates. Proc Natl Acad Sci 103:7718–7722PubMedCrossRefGoogle Scholar
  52. Wright SD, Gillman LN, Ross HA et al (2010) Energy and the tempo of evolution in amphibians. Glob Ecol Biogeogr 19:733–740Google Scholar

Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  1. 1.Department of BiologyStanford UniversityStanfordUSA
  2. 2.Department of Plant and Microbial BiologyUniversity of CaliforniaBerkeleyUSA

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