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Hot spots, cold spots, and the geographic mosaic theory of coevolution

Disturbance frequency and community stability in native tallgrass prairie

The impact of specialized enemies on the dimensionality of host dynamics

Although individual species persist within a web of interactions with other species, data are usually gathered only from the focal species itself. We ask whether evidence of a species’ interactions be detected and understood from patterns in the dynamics of that species alone. Theory predicts that strong coupling between a prey and a specialist predator/parasite should lead to an increase in the dimensionality of the prey's dynamics, whereas weak coupling should not. Here we describe a rare test of this prediction.

Effects of density-dependent and stochastic processes on the regulation of cod populations

NCEAS Portrait: Julie Lowndes Wants the Force of Open Data Science to Be with You

NCEAS Portrait: Julie Lowndes Wants the Force of Open Data Science to Be with You.

Canonical functions for dispersal-induced synchrony

Two processes are universally recognized for inducing spatial synchrony in abundance: dispersal and correlated environmental stochasticity. In the present study we seek the expected relationship between synchrony and distance in populations that are synchronized by density-independent dispersal. In the absence of dispersal, synchrony among populations with simple dynamics has been shown to echo the correlation in the environment. We ask what functional form we may expect between synchrony and distance when dispersal is the synchronizing agent.

Cycles and synchrony: Two historical 'experiments' and one experience

1. Theoretical models predict that spatial synchrony should be enhanced in cyclic populations due to nonlinear phase‐locking. 2. This is supported by Rohani et al.′s (1999) comparison of spatial synchrony of epidemics in two childhood diseases prior to and during the vaccination era. Measles is both more synchronous and more cyclic before vaccination. Whooping cough, in contrast, is more synchronous during the vaccination era, during which multiannual fluctuations are also more conspicuous. 3. Steen et al.

Biological processes and environmental factors regulating the dynamics of the Norwegian Skagerrak Cod populations since 1919

Time series of 0- and 1-group cod sampled in the period 1919 to 1994 at 38 stations along the Norwegian Skagerrak coast were investigated using spatial and temporal analyses. Both groups displayed similar spatial structure and had similar spatial distributions. Spatial heterogeneity occurred on a mesoscale (differences between fjords) and on a local scale (both groups significantly more abundant at sheltered stations in the inner fjord). Temporal fluctuations exhibiting a cyclic component at around 2¿2.5 years were spatially structured on a local scale.

Mathematical methods for identifying representative reserve networks

Optimal release strategies for biological control agents: An application of stochastic dynamic programming to population management