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. 2007 Dec 11;104(50):19891-6.
doi: 10.1073/pnas.0706375104. Epub 2007 Dec 4.

The modularity of pollination networks

Jens M Olesen  1 , Jordi Bascompte, Yoko L Dupont, Pedro Jordano
Affiliations

The modularity of pollination networks

Jens M Olesen et al. Proc Natl Acad Sci U S A. .

Abstract

In natural communities, species and their interactions are often organized as nonrandom networks, showing distinct and repeated complex patterns. A prevalent, but poorly explored pattern is ecological modularity, with weakly interlinked subsets of species (modules), which, however, internally consist of strongly connected species. The importance of modularity has been discussed for a long time, but no consensus on its prevalence in ecological networks has yet been reached. Progress is hampered by inadequate methods and a lack of large datasets. We analyzed 51 pollination networks including almost 10,000 species and 20,000 links and tested for modularity by using a recently developed simulated annealing algorithm. All networks with >150 plant and pollinator species were modular, whereas networks with <50 species were never modular. Both module number and size increased with species number. Each module includes one or a few species groups with convergent trait sets that may be considered as coevolutionary units. Species played different roles with respect to modularity. However, only 15% of all species were structurally important to their network. They were either hubs (i.e., highly linked species within their own module), connectors linking different modules, or both. If these key species go extinct, modules and networks may break apart and initiate cascades of extinction. Thus, species serving as hubs and connectors should receive high conservation priorities.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Fig. 1.
Fig. 1.
Pollination network structure and species roles. The example is from the Andes (28). (A) Nested matrix version of the network, with plant species in columns and pollinator species in rows sorted from the upper left corner according to descending species degree. Colored cells are links between species. (B) Modular matrix version of the same network as in A; species are now sorted according to their modular affinity (order of modules is arbitrary). Red cells are species links gluing the seven modules together into a coherent network, and nonred cells are links within modules (links of the different modules can be identified in A by their color). (C) Graph of modules. Module links are weighted by both the number of species links between modules and number of species within modules; vignettes show dominant pollinator and flower type: black module: Diptera species and mainly white flowers; purple module: small-to-medium-sized beetles, flies, an ant, and small, white/yellow flowers; blue module: butterflies and one plant species, Oxalis species; green module: bees, birds, and large, mainly yellow flowers with a closed morphology; yellow module: large flies and small, yellow umbellifer flowers; orange module: butterflies, a large fly, and white/yellow/pink/purple flowers; and gray module: large flies and mainly small, white flowers. (D) zc-plot of species roles with three module hubs and one connector, but no network hub. In A and B, species acting as module hubs and connectors are shown as blue and green dots, respectively, just outside the matrix border. Notice that the connector species in B (green dot) has >50% of its links outside its own module.
Fig. 2.
Fig. 2.
Distribution of pollinator and plant species according to their network role. Each dot represents a species; large pane includes all 8,233 species from the 29 modular networks. Small panes show role distribution of selected groups of species.
See this image and copyright information in PMC

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References

    1. Montoya JM, Pimm SL, Solé RV. Nature. 2006;442:259–264. - PubMed
    1. Pimm SL. Theor Pop Biol. 1979;16:144–158. - PubMed
    1. Paine RT. J Anim Ecol. 1980;49:667–685.
    1. Pimm SL, Lawton JH. J Anim Ecol. 1980;49:879–898.
    1. Lewinsohn TM, Prado PI, Jordano P, Bascompte J, Olesen JM. Oikos. 2006;113:174–184.

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