Code and data for: Emergence of spatially structured populations by area-concentrated search

The idea that populations are spatially structured has become a very
powerful concept in ecology, raising interest in many research areas.
However, despite dispersal being a core component of the concept, it
typically does not consider the movement behavior underlying any
dispersal. Using individual-based simulations in continuous space, we
investigate the emergence of a spatially structured population in
landscapes with spatially heterogeneous resource distribution and with
organisms following simple area-concentrated search (ACS); individuals do
not, however, perceive or respond to any habitat attributes per se but
only to their foraging success. We investigated effects of different
resource clustering patterns in landscapes (single large cluster vs. many
small clusters) and different resource densities on spatial structure of
populations and movement between resource clusters of individuals. As the
results, we found that foraging success increased with increasing resource
density and decreasing number of resource clusters. In a wide parameter
space, the system exhibited attributes of a spatially structured
population with individuals concentrated in areas of high resource
density, searching within areas of resources, and 'dispersing'
in a straight line between resource patches. 'Emigration' was
more likely from patches that were small or of low quality (low resource
density), but we observed an interaction effect between these two
parameters. With the ACS implemented, individuals tended to move deeper
into a resource cluster in scenarios with moderate resource density than
in scenarios with high resource density. 'Looping' from patches
was more likely if patches were large and of high quality. Our simulations
demonstrate that spatial structure in populations may emerge if critical
resources are heterogeneously distributed and if individuals follow simple
movement rules (such as ACS). Neither the perception of habitat nor an
explicit decision to emigrate from a patch on the side of acting
individuals is necessary for the emergence of spatial structure.