PT  - JOURNAL ARTICLE
AU  - Timothée Poisot
AU  - Sonia Kéfi
AU  - Serge Morand
AU  - Michal Stanko
AU  - Pablo A. Marquet
AU  - Michael E. Hochberg
TI  - A continuum of specialists and generalists in empirical communities
AID  - 10.1101/009985
DP  - 2014 Jan 01
TA  - bioRxiv
PG  - 009985
4099  - http://biorxiv.org/content/early/2014/10/03/009985.short
4100  - http://biorxiv.org/content/early/2014/10/03/009985.full
AB  - Understanding the persistence of specialists and generalists within ecological communities is a topical research question, with far-reaching consequences for the maintenance of functional diversity. Although theoretical studies indicate that restricted conditions may be necessary to achieve co-occurrence of specialists and generalists, analyses of larger empirical (and species-rich) communities reveal the pervasiveness of coexistence. In this paper, we analyze 175 ecological bipartite networks of three interaction types (animal hosts-parasite, plant-herbivore and plant-pollinator), and measure the extent to which these communities are composed of species with different levels of specificity in their biotic interactions. We find a continuum from specialism to generalism. Furthermore, we demonstrate that diversity tends to be greatest in networks with intermediate connectance, and argue this is because of physical constraints in the filling of networks.