Population synchrony in small-world networks

• Published in: Proceedings of the Royal Society B: Biological Sciences
• Main Authors: Ranta, Esa, Fowler, Mike S, Kaitala, Veijo
• Format: Article in Journal/Newspaper
• Language: English
• Published: The Royal Society 2007
• Subjects: Fennoscandia; Lynx
• Online Access: http://dx.doi.org/10.1098/rspb.2007.1546; https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2007.1546; https://royalsocietypublishing.org/doi/full-xml/10.1098/rspb.2007.1546

Network topography ranges from regular graphs (linkage between nearest neighbours only) via small-world graphs (some random connections between nodes) to completely random graphs. Small-world linkage is seen as a revolutionary architecture for a wide range of social, physical and biological networks, and has been shown to increase synchrony between oscillating subunits. We study small-world topographies in a novel context: dispersal linkage between spatially structured populations across a range of population models. Regular dispersal between population patches interacting with density-dependent renewal provides one ecological explanation for the large-scale synchrony seen in the temporal fluctuations of many species, for example, lynx populations in North America, voles in Fennoscandia and grouse in the UK. Introducing a small-world dispersal kernel leads to a clear reduction in synchrony with both increasing dispersal rate and small-world dispersal probability across a variety of biological scenarios. Synchrony is also reduced when populations are affected by globally correlated noise. We discuss ecological implications of small-world dispersal in the frame of spatial synchrony in population fluctuations.