Effects of landscape compositional heterogeneity and spatial
autocorrelation on environmental niche and dispersal in simulated
organisms
Abstract
Local adaptation, environmental tolerance, and dispersal mutually
influence the evolution of one another and each are in turn influenced
by landscape spatial structure. While each of the three have been
investigated frequently in isolation in relation to spatial structure,
the three have rarely been considered together. In this study, we
explored how the magnitude of landscape environmental heterogeneity
(compositional heterogeneity), and environmental spatial autocorrelation
jointly affect the evolution of environmental niche optima, tolerance,
dispersal frequency, and dispersal distance using a spatially explicit
individual based model simulating organisms living, reproducing, and
dispersing within grid-based fractal landscapes. Compositional
heterogeneity tended to have the strongest influence over patterns while
spatial autocorrelation typically played a mediating role. We found that
niche adaptation and dispersal patterns were driven by a balance between
pressure to avoid risk imposed by spatial heterogeneity and pressure to
hedge against risk imposed by temporal environmental fluctuations.
Dispersal frequency and dispersal distance were affected differently by
spatial structure, underscoring the importance of considering the two
independently.