Ecological Modelling 180 (2004) 435–443 The role of heterogeneity on the spatiotemporal dynamics of host–parasite metapopulation  Brajendra K. Singh a , J. Subba Rao a , R. Ramaswamy b , Somdatta Sinha c,∗ a School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India b School of Information Technology, Jawaharlal Nehru University, New Delhi 110067, India c Centre for Cellular and Molecular Biology, Hyderabad 500007, AP, India Received 27 March 2003; received in revised form 15 January 2004; accepted 26 April 2004 Abstract Subpopulations of organisms in different habitat patches may differ from each other in biotic (e.g., inherent growth rate and interaction strength) and abiotic (e.g., climatic and landscape pattern) components. Such heterogeneity can influence the mode and extent of dispersal of individuals among these subpopulations, which, in turn, may regulate their spatiotemporal dynamics. We have modelled a homogeneous metapopulation of the interacting host and parasite system, with closed boundary and dispersal limited to nearest neighbours, using the spatially explicit coupled map lattice approach. We have studied the role of heterogeneity in terms of landscape fragmentation and demographic heterogeneity on the spatiotemporal dynamics. The homogeneous metapop- ulation shows spatiotemporally synchronous dynamics in the long-term, which is independent of the exact forms of the dispersal function considered commonly. The primary role of both types of heterogeneity is to resist evolution of spatiotemporal synchrony in the lattice, and the dynamics in the metapopulation remains asynchronous for a very long time. Spatiotemporal synchrony in species population may be detrimental to persistence and is a potential problem for conservation biologists. Thus, evolution and maintenance of ecological and demographic diversity in nature seem to aid in species persistence at a metapopulation level. © 2004 Elsevier B.V. All rights reserved. Keywords: Landscape fragmentation; Asynchrony; Demographic heterogeneity; Coupled map lattice; Dispersal 1. Introduction In nature, a metapopulation consists of subpopu- lations having non-identical behavioural and demo- graphic properties, and occupying habitats of variable extent/quality and connectivity. Functional dynamics of those species, which have the capability to induce damage to other species (e.g., a parasite or pathogen),  Supplementary data associated with this article can be found, in the online version, at doi:10.1016/j.ecolmodel.2004.04.031. ∗ Corresponding author. Tel.: +91-40-27192588/27160222x2588/2786; fax: +91-40-27160591/27160311. E-mail address: sinha@ccmb.res.in (S. Sinha). assume larger importance in the metapopulation con- text. The classical model to study the growth of the interacting host (H) and parasite (P) populations (Nicholson and Bailey, 1935) is inherently unstable and extinct-prone. Some studies (May, 1978; Reeve, 1988), aimed at resolving this stability problem, have considered the effect of environmental variability on persistence of a “population” of sub-populations of these H–P models. These studies considered the sta- tistical aspect of the stability of the H–P dynamics rather than the effects of variable environment on the spatiotemporal pattern formation and dynamics. Later studies (Hassell et al., 1991, 1994; Comins et al., 1992) used the spatially extended models of the H–P 0304-3800/$ – see front matter © 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.ecolmodel.2004.04.031