Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Body-size shifts in aquatic and terrestrial urban communities


Body size is intrinsically linked to metabolic rate and life-history traits, and is a crucial determinant of food webs and community dynamics1,2. The increased temperatures associated with the urban-heat-island effect result in increased metabolic costs and are expected to drive shifts to smaller body sizes3. Urban environments are, however, also characterized by substantial habitat fragmentation4, which favours mobile species. Here, using a replicated, spatially nested sampling design across ten animal taxonomic groups, we show that urban communities generally consist of smaller species. In addition, although we show urban warming for three habitat types and associated reduced community-weighted mean body sizes for four taxa, three taxa display a shift to larger species along the urbanization gradients. Our results show that the general trend towards smaller-sized species is overruled by filtering for larger species when there is positive covariation between size and dispersal, a process that can mitigate the low connectivity of ecological resources in urban settings5. We thus demonstrate that the urban-heat-island effect and urban habitat fragmentation are associated with contrasting community-level shifts in body size that critically depend on the association between body size and dispersal. Because body size determines the structure and dynamics of ecological networks1, such shifts may affect urban ecosystem function.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Map of the study area.
Fig. 2: Micro-climatic urban-heat-island effects.
Fig. 3: Taxon-specific percentage change in CWMBS for a 0–25% change in urbanization.
Fig. 4: Taxon-specific plots of CWMBS as a function of urbanization.

Similar content being viewed by others


  1. Woodward, G. et al. Body size in ecological networks. Trends Ecol. Evol. 20, 402–409 (2005).

    Article  PubMed  Google Scholar 

  2. Brown, J. H., Gillooly, J. F., Allen, A. P., Savage, V. M. & West, G. B. Toward a metabolic theory of ecology. Ecology 85, 1771–1789 (2004).

    Article  Google Scholar 

  3. Scheffers, B. R. et al. The broad footprint of climate change from genes to biomes to people. Science 354, aaf7671 (2016).

    Article  PubMed  CAS  Google Scholar 

  4. Alberti, M., Marzluff, J. & Hunt, V. M. Urban driven phenotypic changes: empirical observations and theoretical implications for eco-evolutionary feedback. Phil. Trans. R. Soc. Lond. B 372, 20160029 (2017).

    Article  Google Scholar 

  5. Cheptou, P. O., Hargreaves, A. L., Bonte, D. & Jacquemyn, H. Adaptation to fragmentation: evolutionary dynamics driven by human influences. Phil. Trans. R. Soc. Lond. B 372, 20160037 (2017).

    Article  Google Scholar 

  6. Chown, S. L. & Gaston, K. J. Body size variation in insects: a macroecological perspective. Biol. Rev. Camb. Philos. Soc. 85, 139–169 (2010).

    Article  PubMed  Google Scholar 

  7. Kalinkat, G. et al. Body masses, functional responses and predator–prey stability. Ecol. Lett. 16, 1126–1134 (2013).

    Article  PubMed  Google Scholar 

  8. Brose, U. et al. Predicting the consequences of species loss using size-structured biodiversity approaches. Biol. Rev. Camb. Philos. Soc. 92, 684–697 (2017).

    Article  PubMed  Google Scholar 

  9. Horne, C. R., Hirst, A. G. & Atkinson, D. Seasonal body size reductions with warming covary with major body size gradients in arthropod species. Proc. R. Soc. B 284, 20170238 (2017).

    Article  PubMed  PubMed Central  Google Scholar 

  10. Seto, K. C., Güneralp, B. & Hutyra, L. R. Global forecasts of urban expansion to 2030 and direct impacts on biodiversity and carbon pools. Proc. Natl Acad. Sci. USA 109, 16083–16088 (2012).

    Article  PubMed  PubMed Central  ADS  Google Scholar 

  11. Youngsteadt, E., Dale, A. G., Terando, A. J., Dunn, R. R. & Frank, S. D. Do cities simulate climate change? A comparison of herbivore response to urban and global warming. Glob. Chang. Biol. 21, 97–105 (2015).

    Article  PubMed  ADS  Google Scholar 

  12. Ward, K., Lauf, S., Kleinschmit, B. & Endlicher, W. Heat waves and urban heat islands in Europe: a review of relevant drivers. Sci. Total Environ. 569-570, 527–539 (2016).

    Article  PubMed  ADS  CAS  Google Scholar 

  13. Niemelä. J. Urban Ecology: Patterns, Processes, and Applications (Oxford Univ. Press, Oxford, 2011).

  14. Atkinson, D. Temperature and organism size: a biological law for ectotherms? Adv. Ecol. Res 25, 1–58 (1994).

    Article  Google Scholar 

  15. Bonte, D. & Dahirel, M. Dispersal: a central and independent trait in life history. Oikos 126, 472–479 (2017).

    Article  Google Scholar 

  16. Piano, E. et al. Urbanization drives community shifts towards thermophilic and dispersive species at local and landscape scales. Glob. Chang. Biol. 23, 2554–2564 (2017).

    Article  PubMed  ADS  Google Scholar 

  17. Concepción, E. D., Moretti, M., Altermatt, F., Nobis, M. P. & Obrist, M. K. Impacts of urbanisation on biodiversity: the role of species mobility, degree of specialisation and spatial scale. Oikos 124, 1571–1582 (2015).

    Article  Google Scholar 

  18. Arnfield, A. J. Two decades of urban climate research: a review of turbulence, exchanges of energy and water, and the urban heat island. Int. J. Climatol. 23, 1–26 (2003).

    Article  Google Scholar 

  19. Benjamini, Y. & Hochberg, Y. Controlling the false discovery rate: a practical and powerful approach to multiple testing. J. R. Stat. Soc. B Stat. Methodol. 57, 289–300 (1995).

    MathSciNet  MATH  Google Scholar 

  20. Forster, J., Hirst, A. G. & Atkinson, D. Warming-induced reductions in body size are greater in aquatic than terrestrial species. Proc. Natl Acad. Sci. USA 109, 19310–19314 (2012).

    Article  PubMed  PubMed Central  ADS  Google Scholar 

  21. Dahirel, M., Dierick, J., De Cock, M. & Bonte, D. Intraspecific variation shapes community-level behavioral responses to urbanization in spiders. Ecology 98, 2379–2390 (2017).

    Article  PubMed  Google Scholar 

  22. McDonnell, M. J. & Hahs, A. K. Adaptation and adaptedness of organisms to urban environments. Annu. Rev. Ecol. Evol. Syst. 46, 261–280 (2015).

    Article  Google Scholar 

  23. Alberti, M. et al. Global urban signatures of phenotypic change in animal and plant populations. Proc. Natl Acad. Sci. USA 114, 8951–8956 (2017).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  24. Johnson, M. T. J. & Munshi-South, J. Evolution of life in urban environments. Science 358, eaam8327 (2017).

    Article  PubMed  CAS  Google Scholar 

  25. Schramski, J. R., Dell, A. I., Grady, J. M., Sibly, R. M. & Brown, J. H. Metabolic theory predicts whole-ecosystem properties. Proc. Natl Acad. Sci. USA 112, 2617–2622 (2015).

    Article  PubMed  PubMed Central  ADS  CAS  Google Scholar 

  26. Malerba, M. E., White, C. R. & Marshall, D. J. Eco-energetic consequences of evolutionary shifts in body size. Ecol. Lett. 21, 54–62 (2018).

    Article  PubMed  Google Scholar 

  27. Osmond, M. M. et al. Warming-induced changes to body size stabilize consumer–resource dynamics. Am. Nat. 189, 718–725 (2017).

    Article  PubMed  Google Scholar 

  28. Gianuca, A. T., Pantel, J. H. & De Meester, L. Disentangling the effect of body size and phylogenetic distances on zooplankton top-down control of algae. Proc. R. Soc. B 283, 20160487 (2016).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  29. Agosta, S. J. & Janzen, D. H. Body size distributions of large Costa Rican dry forest moths and the underlying relationship between plant and pollinator morphology. Oikos 108, 183–193 (2005).

    Article  Google Scholar 

  30. Biesmeijer, J. C. et al. Parallel declines in pollinators and insect-pollinated plants in Britain and the Netherlands. Science 313, 351–354 (2006).

    Article  PubMed  ADS  CAS  Google Scholar 

  31. Duffy, J. E. Biodiversity loss, trophic skew and ecosystem functioning. Ecol. Lett. 6, 680–687 (2003).

    Article  Google Scholar 

  32. Webb, C. T., Hoeting, J. A., Ames, G. M., Pyne, M. I. & LeRoy Poff, N. A structured and dynamic framework to advance traits-based theory and prediction in ecology. Ecol. Lett. 13, 267–283 (2010).

    Article  PubMed  Google Scholar 

  33. Threlfall, C. G. et al. Increasing biodiversity in urban green spaces through simple vegetation interventions. J. Appl. Ecol. 54, 1874–1883 (2017).

    Article  Google Scholar 

  34. IBZ. Bevolkingscijfers per Provincie en per Gemeente op 1 Januari 2017 (Federale Overheidsdienst Binnenlandse Zaken, 2017).

  35. De Saeger, S. et al. Biologische Waarderingskaart en Natura 2000 Habitatkaart (Instituut voor Natuur en Bosonderzoek, Brussels, 2016).

  36. Packet, J. et al. Watervlakken Versie 1.0: Polygonenkaart van Stilstaand Water in Vlaanderen. Inhoud en Metadata van een Nieuw Instrument voor Water-, Milieu- en Natuurbeleid (Instituut voor Natuur en Bosonderzoek, Brussels, 2017).

  37. Burnham, K. P. & Anderson, D. R. Model Selection and Multimodel Inference: a Practical Information-Theoretic Approach (Springer Science & Business Media, New York, 2003).

    MATH  Google Scholar 

  38. R Development Core Team. R: A Language and Environment for Statistical Computing (R Foundation for Statistical Computing, Vienna, 2015).

  39. Bink, F. A. Ecologische Atlas van de Dagvlinders van Noordwest-Europa (Schuyt & Co, Haarlem, 1992).

    Google Scholar 

  40. Sekar, S. A meta-analysis of the traits affecting dispersal ability in butterflies: can wingspan be used as a proxy? J. Anim. Ecol. 81, 174–184 (2012).

    Article  PubMed  Google Scholar 

  41. Stevens, V. M., Trochet, A., Van Dyck, H., Clobert, J. & Baguette, M. How is dispersal integrated in life histories: a quantitative analysis using butterflies. Ecol. Lett. 15, 74–86 (2012).

    Article  PubMed  Google Scholar 

  42. Stevens, V. M. et al. A comparative analysis of dispersal syndromes in terrestrial and semi-terrestrial animals. Ecol. Lett. 17, 1039–1052 (2014).

    Article  PubMed  Google Scholar 

  43. Manley, C. British Moths and Butterflies: a Photographic Guide (A & C Black, London, 2008).

    Google Scholar 

  44. Nieminen, M., Rita, H. & Uuvana, P. Body size and migration rate in moths. Ecography 22, 697–707 (1999).

    Article  Google Scholar 

  45. Slade, E. M. et al. Life-history traits and landscape characteristics predict macro-moth responses to forest fragmentation. Ecology 94, 1519–1530 (2013).

    Article  PubMed  Google Scholar 

  46. Reinhardt, K., Köhler, G., Maas, S. & Detzel, P. Low dispersal ability and habitat specificity promote extinctions in rare but not in widespread species: the Orthoptera of Germany. Ecography 28, 593–602 (2005).

    Article  Google Scholar 

  47. Roberts, M. J. The Spiders of Great Britain and Ireland: Compact Edition (Apollo Books, Vester Skerninge, 2009).

    Google Scholar 

  48. Turin, H. De Nederlandse Loopkevers: Verspreiding en Ecologie (KNNV, Zeist, 2000).

    Google Scholar 

  49. Duff, A. G. et al. Beetles of Britain and Ireland 4 (A. G. Duff, West Runton, 2016).

    Google Scholar 

  50. Donner, J. Ordnung Bdelloidea. Bestimmungsbücher zur Bodenfauna Europas (Akademie-Verlag, Berlin, 1965).

    Google Scholar 

  51. Fontaneto, D. Biogeography of Microscopic Organisms: is Everything Small Everywhere? (Cambridge Univ. Press, Cambridge, 2011).

    Book  Google Scholar 

  52. Meisch, C. Freshwater Ostracoda of Western and Central Europe (Spektrum Akademischer, Heidelberg, 2000).

    Google Scholar 

  53. Bilton, D. T., Freeland, J. R. & Okamura, B. Dispersal in freshwater invertebrates. Annu. Rev. Ecol. Syst. 32, 159–181 (2001).

    Article  Google Scholar 

  54. De Bie, T. et al. Body size and dispersal mode as key traits determining metacommunity structure of aquatic organisms. Ecol. Lett. 15, 740–747 (2012).

    Article  PubMed  Google Scholar 

  55. Brans, K. I. et al. Eco-evolutionary dynamics in urbanized landscapes: evolution, species sorting and the change in zooplankton body size along urbanization gradients. Phil. Trans. R. Soc. Lond. B 372, 20160030 (2017).

    Article  Google Scholar 

  56. Gianuca, A. T. et al. Taxonomic, functional and phylogenetic metacommunity ecology of cladoceran zooplankton along urbanization gradients. Ecography 41, 183–194 (2018).

    Article  Google Scholar 

Download references


We thank M. De Cock, J. Dierick, P. Limbourg, E. van den Berg, M. Van Kerckvoorde and P. Vantieghem for help with sampling and identification of species. This is publication BRC419 of the Biodiversity Research Centre (UCL/ELI). This research is part of the SPEEDY-project, funded by the Interuniversity Attraction Poles program of the Belgian Science Policy Office BELSPO (IAP-grant P7/04).

Reviewer information

Nature thanks M. McDonnell and the other anonymous reviewer(s) for their contribution to the peer review of this work.

Author information

Authors and Affiliations



T.M., L.D.M. and H.V.D. conceived the study. C.S. and L.D.M. coordinated the consortium. T.M., C.S., A.K., L.F.B., T.B., D.B., K.I.B., M.C., M.D., N.D., K.D.W., J.M.T.E., D.F., A.T.G., L.G., F.H., J.H., L.L., K.M., E.M., E.P., R.S., I.S. and K.V.D. contributed to sampling and data collection. T.M. and A.K. performed the analyses. H.M. selected study plots, calculated fragmentation variables and designed the study area map. T.M. wrote the first draft of the manuscript with all authors contributing substantially to revisions.

Corresponding author

Correspondence to Thomas Merckx.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data figures and tables

Extended Data Fig. 1 Micro-climatic urban-heat-island effect strengths.

a, b, Slopes of the urban-heat-island effects (measured as the increase in temperature (°C) per 1% increase in percentage BUC) as a function of spatial scale (the radius at which urbanization was quantified) with 95% confidence intervals (CI). Separate measurements are shown for summer (red) and winter (blue) using merged readings for pond, grassland and woodland habitats (n = 104 sites). a, Diurnal measurements. b, Nocturnal measurements. Data points are offset from one another horizontally to improve clarity.

Extended Data Fig. 2 Correlations between urbanization and habitat fragmentation.

Correlations between urbanization (measured as the percentage BUC) and three habitat fragmentation variables: habitat coverage (a, b), mean size of habitat patches (c, d), and mean nearest-neighbour distance among habitat patches (e, f). Separate plots are shown for terrestrial (that is, all types of (semi-)natural habitat, a, c, e) and aquatic (that is, all pond types, b, d, f) habitats (n = 27 landscape-scale sampling plots). Pearson’s r coefficients and P values are indicated; not significant (NS), P > 0.1; *P < 0.05; ***P < 0.001.

Extended Data Table 1 Taxon-specific details of sampling procedures, body-size data and size–dispersal links
Extended Data Table 2 Model output of average temperature in relation to urbanization and habitat type
Extended Data Table 3 Model output of CWMBS in relation to urbanization
Extended Data Table 4 Model output of abundance and diversity measures in relation to urbanization

Supplementary information

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Merckx, T., Souffreau, C., Kaiser, A. et al. Body-size shifts in aquatic and terrestrial urban communities. Nature 558, 113–116 (2018).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing