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can the topological properties of these networks tell us about the dynamics of spatial
processes?
14.4.2. Unraveling the dynamics of spatial networks
Following on the last case study, the spatial structure of the roosting network can
provide insights into the functionality of roost changes and social grouping or seg-
regation by describing the way that information, diseases, or parasites can travel
through the network. The compartmentalized structure implies that each colony of
bats uses a subset of trees for shelter and bats from one colony only occasionally
use trees belonging to the subset of trees used by the other colonies. This structure
slows down the spread of diseases and the exchange of information through the
entire network. The correlation between network structure and infection dynamics
was showed by the use of a simple epidemiological model [Fortuna et al. (2008b)].
We can go further and ask what changes must happen to the spatial dynamics in
order to maintain the structure of the roosting network? That is, if some trees
disappear, will the colonies reorganize the use of trees in order to best preserve in-
dividual colonies' knowledge by minimizing the transfer of information about food
resources to outsiders?
Considering instead the spatial network of temporary ponds used by amphibian
species [Fortuna et al. (2006)]. Habitat loss experiments, analogous to the removal
of species in food webs and plant-animal mutualistic networks, can tell us the im-
portance of keystone patches on the persistence of the species. In the same way, we
can estimate where would be the most suitable site to create a new pond in order to
most eectively increase the connectivity during, for example, an especially intense
dry season. It would also be interesting to explore how the structure of the network
inuences the dispersal movements of amphibian species. Could particular network
topologies connecting the temporary ponds induce changes in the dispersal kernels
of amphibians?
The most challenging and promising eld for the application of networks of spa-
tial dynamics is within population genetics. We have seen how network approaches
can shed light into the characterization of gene ow patterns inside a tree popula-
tion [Fortuna et al. (2008a)]. We can also investigate the dynamical implications
of the patterns of intraspecic genetic variability among populations. These pat-
terns can be well-characterized with spatial network approaches, as demonstrated
by Dyer and Nason (2004). They described the statistical relationships between all
populations simultaneously dening a \population graph" that can also be viewed
as a \genetic landscape". In a genetic landscape, nodes represent populations and
a link indicates a high degree of genetic similarity between them [Dyer and Nason
(2004)]. What are the dynamical implications of the topology of the genetic land-
scape on microevolutionary processes, as these ultimately can lead to a signicant
evolutionary change? Do the dynamics of communities generate a universal spatial
pattern in the distribution of genetic variability between species?
