Paul Higgs - Research Topics - Food Webs

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Paul Higgs - Research Topics

Food Web Structure and the Dynamics of Multi-species Communities

Collaborators:

Alan McKane

Chris Quince

Barbara Drossel.

Publications

  1. Quince, C., Higgs, P.G. & McKane, A.J. (2005) Topological structure and interaction strengths in model food webs. Ecological Modelling 187, 389-412.
  2. Quince, C., Higgs, P.G. & McKane, A.J. (2005) Deleting species from model food webs. Oikos 110, 283-296.
  3. Quince, C., Higgs, P.G. & McKane, A.J. (2002) Food Web Structures and the Evolution of Biological Communities. In Biological Evolution and Statistical Physics. Eds. Lässig, M. & Valleriani, A. Lecture Notes in Physics 585, 281-298. Springer Verlag.
  4. Drossel, B., Higgs, P.G. & McKane (2001) The influence of predator-prey population dynamics on the long-term evolution of food web structure.J. Theor. Biol. 208, 91-107.
  5. Caldarelli, G., Drossel, B., Higgs, P.G. & McKane, A.J. (2000) Using stochastic dynamics to model multispecies communities, in Stochastic and Chaotic Dynamics in the Lakes, D. S. Broomhead, E. A. Luchinskaya, P. V. E. McClintock and T. Mullin (eds), (American Institute of Physics, Melville, NY) pp 226-231.
  6. Caldarelli, G., Higgs, P.G. & McKane, A.J. (1998). Modelling Coevolution in Multi-species Communities. J. Theor. Biol. 193, 345-358.

 

The influence which any species has on other species in an ecosystem is determined by ecological interactions such as competition and predation. Therefore to understand multi-species coevolution we need a realtistic model of food web structure. The ecological communities which we see have not been randomly thrown together – they have evolved. Therefore to understand food web structure we need a realistic model of coevolution.

Webworld is a program which models the structure of food webs and the dynamics of these webs on both ecological and evolutionary timescales. We aim to describe food web properties such as numbers of top, basal and intermediate species, numbers of links per species, and lengths of food chains, and to compare these to the properties of real webs. We are also looking at the dynamics of speciation and extinction events in the model, and comparing this to observations in the fossil record.

We are also interested in the details of the differential equations used to describe population dynamics in multi-species communities. We are currently comparing different typed of functional responses (Lotka-Volterra, Ratio-Dependent, and others) to see how these effect the static and dynamic properties of food webs.