The relationship between predator and prey body sizes is an important property of food webs with potential implications for community dynamics and ecosystem functioning. To shed more light on this issue I here analyze the relationships between prey size, predator size and trophic position of consumers, using body size estimates of 697 species in 52 food webs. First I show that the relationship between predator and prey body sizes across many systems can be different from, and potentially obscure the true relationship within systems. More specifically, when data from all webs are aggregated average prey size is positively correlated to predator size with a regression slope less than unity, suggesting that predators become less similar in size to their average prey the larger the predator is, and consequently that the relative size difference between a predator and its prey should increase with the trophic position of the consumer. However, despite this I find the predator-prey body mass ratio to be negatively correlated to the trophic position of the consumer within many webs. The reason for this is that the across-webs pattern is not representative for the within-web relationship. Second, I show that the pattern observed is not compatible with a simple null-model for the distribution of trophic links between predators and prey. The observed relationship between predator size and mean prey size is for most webs significantly steeper than that predicted by the cascade model. Furthermore, the observed relationship also deviates significantly (but less so) from an ecologically more realistic model for the distribution of trophic links (the niche model). The results contradict the traditional Eltonian paradigm that predator-prey body mass ratios do not vary consistently across trophic levels. It is concluded that more studies are needed to establish the generality of the results and explore its dynamical implications.
Aljetlawi, A.A., Sparrevik, E. and Leonardsson, K. 2004. Preypredator size-dependent functional response: derivation and rescaling to the real world. J. Animal Ecol. 73: 239–252.
Banasek-Richter, C., Cattin, M.F. and Bersier, L.F. 2004. Sampling effects and the robustness of quantitative and qualitative food-web descriptors. J. Theor. Biol. 226: 23–32.
Berg, S., Christianou, M., Jonsson, T. and Ebenman, B. 2011. Using sensitivity analysis to identify keystone species and keystone links in size-based food webs. Oikos 120: 510–519.
Berlow, E.L., Dunne, J.A., Martinez, N.D., Stark, P.B., Williams, R.J. and Brose, U. 2009. Simple prediction of interaction strengths in complex food webs. PNAS 106: 187–191.
Bersier, L.F. and Kehrli, P. 2008. The signature of phylogenetic constraints on food-web structure. Ecol. Complex. 5: 132–139.
Boit A., Martinez N.D., Williams, R.J. and Gaedke, U. 2012. Mechanistic theory and modelling of complex food-web dynamics in Lake Constance. Ecol. Lett. 15: 594–602.
Brose, U. 2008. Complex food webs prevent competitive exclusion among producer species. PNAS 275: 2507–2514.
Brose, U. 2010. Body-mass constraints on foraging behaviour determine population and food-web dynamics. Funct. Ecol. 24: 28–34.
Brose, U., Cushing, L., Berlow, E.L., Jonsson, T., Banasek-Richter, C., Bersier, L.F., Blanchard, J.L., Brey, T., Carpenter, S.R., Cattin Blandenier, M.-F., Cohen, J.E., Dawah, H.A., Dell, T., Edwards, F., Harper-Smith, S., Jacob, U., Knapp, R.A., Ledger, M.E., Memmott, J., Mintenbeck, K., Pinnegar, J.K., Rall, B.C., Rayner, T., Ruess, L., Ulrich, W., Warren, P., Williams, R.J., Woodward, G., Yodzis, P. and Martinez, N.D. 2005. Body sizes of consumers and their resources. Ecology 86: 2545.
Brose, U., Ehnes, R.B., Rall, B.C., Vucic-Pestic, O., Berlow, E.L. and Scheu, S. 2008. Foraging theory predicts predator-prey energy fluxes. J. Animal Ecol. 77: 1072–1078.
Brose, U., Jonsson, T., Berlow, E.L., Warren, P., Banasek-Richte,r C., Bersier, L.F., Blanchard, J.L., Brey, T., Carpenter, S.R., Cattin Blandenier, M.-F., Cushing, L., Dawah, H.A., Dell, T., Edwards, F., Harper-Smith, S., Jacob, U., Ledger, M.E., Martinez, N.D., Memmott, J., Mintenbeck, K., Pinnegar, J.K., Rall, B.C., Rayner, T., Reuman, D.C., Ruess, L., Ulrich, W., Williams, R.J., Woodward, G. and Cohen, J.E. 2006a. Consumer-resource bodysize relationships in natural food webs. Ecology 87: 2411–2417.
Brose, U., Williams, R.J. and Martinez, N.D. 2006b. Allometric scaling enhances stability in complex food webs. Ecol. Lett. 9: 1228–1236.
Brown, J.H., Gillooly, J.F., Allen, A.P., Savage, V.M. and West, G.B. 2004. Toward a metabolic theory of ecology. Ecology 85: 1771–1789.
Calder, W.A. 1984. Size, function, and life history. Harvard University Press, Cambridge, MA, USA.
Cattin, M.F., Bersier, L.F., Banasek-Richter, C., Baltensperger, R. and Gabriel, J.P. 2004. Phylogenetic constraints and adaptation explain food-web structure. Nature 427: 835–839.
Cohen, J.E. 1977. Ratio of prey to predators in community webs. Nature 270:165–167
Cohen, J.E. 1978. Food webs and niche space. Monographs in Population Biology 11. Princeton University Press
Cohen, J.E. 1989a. ECOWeB; Ecologists’ Co-Operative Web Bank. The Rockefeller University,
Cohen, J.E. 1989b. Food webs and community structure. - In: Roughgarden, J., May, R.M. and Levin, S.A. (eds.), Perspectives in ecological theory. Princeton University Press, Princeton, NJ, USA, pp. 181–202.
Cohen, J.E., Briand, F. and Newman, C.M. 1990. Community food webs: data and theory. Springer Verlag, Berlin, Germany.
Cohen, J.E., Jonsson, T. and Carpenter, S.R. 2003. Ecological community description using the food web, species abundance, and body size. PNAS 100: 1781–1786.
Cohen, J.E. and Newman, C.M. 1985. A stochastic theory of community food webs I. Models and aggregated data. Proc. Royal Soc. London, Series B 224: 421–448.
Cohen, J.E., Pimm, S.L., Yodzis, P. and SaldañAAAA, J. 1993. Body sizes of animal predators and animal prey in food webs. J. Animal Ecol. 62: 67–78.
Costa, G.C. 2009. Predator size, prey size, and dietary niche breadth relationships in marine predators. Ecology 90: 2014–2019.
De Ruiter, P., Neutel, A.-M. and Moore, J.C. 1995. Energetics, patterns of interaction strengths, and stability in real ecosystems. Science 269: 1257–1260.
Emmerson, M.C., Montoya, J.M. and Woodward, G. 2005. Body size, interaction strength, and food web dynamics. In: deRuiter P.C, Wolters V. and Moore J.C. (eds.), Dynamic food webs. Academic Press, Boston, MA, USA, pp. 167–178.
Emmerson, M.C. and Raffaelli, D. 2004. Predator-prey body size, interaction strength and the stability of a real food web. J. Animal Ecol. 73: 399–409.
Elton, C. 1927. Animal Ecology. Reprint, 2001, University of Chicago Press edn. Sidgewick and Jackson, London.
Goldwasser, L. and Roughgarden, J. 1997. Sampling effects and the estimation of food web properties. Ecology 78: 41–54.
Gotelli, N.J. and Graves, G.R. 1997. Null Models in Ecology. Smithsonian Institution Press, Washington, USA.
Ings, T.C., Montoya, J.M., Bascompte, J., Bluthgen, N., Brown, L., Dormann, C.F., Edwards, F., Figueroa, D., Jacob, U., Jones, J.I., Lauridsen, R.B., Ledger, M.E., Lewis, H.M., Olesen, J.M., van Veen, F.J.F., Warren, P.H. and Woodward, G. 2009. Ecological networks - beyond food webs. J. Animal Ecol. 78: 253–269.
Jonsson, T. 1998 Food webs and the distribution of body sizes. Linköping studies in Science and Technology. Dissertation No. 535, UniTryck, Linköping, Sweden.
Jonsson ,T., Cohen, J.E. and Carpenter, S.R. 2005. Food webs, body size, and species abundance in ecological community description. Adv. Ecol. Res. 36: 1–84.
Jonsson, T. and Ebenman, B. 1998. Effects of predator-prey body size ratios on the stability of food chains. J. Theor. Biol. 193: 407–417.
Loeuille, N. and Loreau, M. 2004. Nutrient enrichment and food chains: can evolution buffer top-down control? Theor. Popul. Biol. 65: 285–298.
Martinez, N. D. 1994. Scale-dependent constraints on food-web structure. Amer. Nat. 144: 935–953.
McCann, K., Hastings, A. and Huxel, G.R. 1998. Weak trophic interactions and the balance of nature. Nature 395: 794–798.
Neubert, M.G., Blumenshine, S.C., Duplisea, D.E., Jonsson, T. and Rashleigh, B. 2000. Body size and food web structure: testing the equiprobability assumption of the cascade model. Oecologia 123: 241–251.
Neutel, A.-M., Heesterbeek, J.A.P. and De Ruiter, P.C. 2002. Stability in real food webs: weak links in long loops. Science 296: 1120–1123.
Neutel, A.M., Heesterbeek, J.A.P., van de Koppel, J., Hoenderboom, G., Vos, A., Kaldeway, C., Berendse, F. and de Ruiter, P.C. 2007. Reconciling complexity with stability in naturally assembling food webs. Nature 449: 599–602.
O’Gorman, E. J., Jacob, U., Jonsson, T. and Emmerson, M.C. 2010. Interaction strength, food web topology and the relative importance of species in food webs. J. Animal Ecol. 79: 682–692.
Otto, S.B., Berlow, E.L., Rank, N.E., Smiley, J. and Brose, U. 2008. Predator diversity and identity drive interaction strength and trophic cascades in a food web. Ecology 89: 134–144.
Otto, S.B., Rall, B.C. and Brose, U. 2007. Allometric degree distributions facilitate food-web stability. Nature 450: 1226–1229.
Paine, R.T. 1988. Food webs: road maps of interactions or grist for theoretical development? Ecology 69: 1648–1654.
Persson, L., Leonardsson, K., de Roo,s A.M., Gyllenberg, M. and Christensen, B. 1998. Ontogenetic scaling of foraging rates and the dynamics of a size-structured consumer-resource model. Theor. Popul. Biol. 54: 270–293.
Petchey, O.L., Beckerman, A.P., Riede, J.O. and Warren, P.H. 2008. Size, foraging, and food web structure. PNAS 105: 4191–4196.
Peters, R.H. 1983. The ecological implications of body size. Cambridge University Press, New York, USA.
Peters, R.H. 1988. Some general problems for ecology illustrated by food web theory. Ecology 69: 1673–1676.
Pimm, S.L. and Lawton, J.H. 1977. Number of trophic levels in ecological communities. Nature 268: 329–331.
Pimm, S.L. and Lawton, J.H. 1978. On feeding on more than one trophic level. Nature 275: 542–544.
Rall, B.C., Guill, C. and Brose, U. 2008. Food-web connectance and predator interference dampen the paradox of enrichment. Oikos 117: 202–213.
Reuman, D.C. and Cohen, J.E. 2005. Estimating relative energy fluxes using the food web, species abundance, and body size. Adv. Ecol. Res. 36: 137–182.
Reuman, D.C., Mulder, C., Banasek-Richter, C., Blandenier, M.F.C., Breure, A.M., Den Hollander, H., Kneitel, J.M., Raffaelli, D., Woodward, G. and Cohen, J.E. 2009. Allometry of Body Size and Abundance in 166 Food Webs. Adv. Ecol. Res. 41: 1–44.
Riede, J.O., Brose, U., Ebenman, B., Jacob, U., Thompson, R., Townsend, C. R. and Jonsson, T. 2011. Stepping in Elton’s foot- prints: a general scaling model for body masses and trophic levels across ecosystems. Ecol. Lett. 14: 169–178.
Rooney, N., McCann, K., Gellner, G. and Moore, J.C. 2006. Structural asymmetry and the stability of diverse food webs. Nature 442: 265–269.
Schoener, T.W. 1989. Food webs from the small to the large. Ecology 70: 1559–1589.
Stouffer, D.B., Camacho, J., Guimera, R., Ng, C.A. and Amaral, L.A.N. 2005. Quantitative patterns in the structure of model and empirical food webs. Ecology 86: 1301–1311.
Vézina, A.F. 1985. Empirical relationships between predator and prey size among terrestrial vertebrate predators. Oecologia 67: 555–565.
Vucic-Pestic, O., Rall, B.C., Kalinkat, G. and Brose, U. 2010. Allometric functional response model: body masses constrain interaction strengths. J. Animal Ecol. 79: 249–256.
Warren, P.H. and Lawton, J.H. 1987. Invertebrate predator-prey body size relationships - an explanation for upper-triangular food webs and patterns in food web structure. Oecologia 74: 231–235.
Weitz, J.S. and Levin, S.A. 2006. Size and scaling of predator-prey dynamics. Ecol. Lett. 9: 548–557.
Williams, R.J. and Martinez, N.D. 2000. Simple rules yield complex food webs. Nature 404: 180–183.
Williams, R.J. and Martinez, N.D. 2004. Limits to trophic levels and omnivory in complex food webs: theory and data. Am. Nat. 163: 458–468.
Williams, R.J. and Martinez, N.D. 2008. Success and limits among structural models of complex food webs. J. Animal Ecol. 77: 512–519.
Woodward, G., Ebenman, B., Ernmerson, M., Montoya, J.M., Olesen, J.M., Valido, A. and Warren, P.H. 2005. Body size in ecological networks. Trends Ecol. Evol. 20: 402–409.
Wootton, J.T. and Emmerson, M. 2005. Measurement of interaction strength in nature. Annual Rev. Ecol. Evol. Systems 36: 419–444.
Yodzis, P. 1984. Energy flow and the vertical structure of real ecosystems. Oecologia 65: 86–88.
About this article
Cite this article
Jonsson, T. Trophic links and the relationship between predator and prey body sizes in food webs. COMMUNITY ECOLOGY 15, 54–64 (2014). https://doi.org/10.1556/ComEc.15.2014.1.6
- Cascade model
- Food webs
- Niche model
- Predator-prey body size ratios
- Trophic links
- Trophic structure