Pollinators and plants as ecosystem engineers: post-dispersal fruits provide new habitats for other organisms

Ecosystem engineering consists of a ubiquitous and fundamental class of interactions where some organisms promote state changes in biotic and abiotic materials which indirectly affect others. Since the concept was created as a counterpoint to traditional flux-based models, pollinators have never been considered to promote ecosystem engineering because they modulate the supply of resources used by seed/fruit consumers. However, dry fruits may persist in the environment for long periods after seed dispersion as empty structures that are an additional alternative for occupancy. These increase the realized niche of some organisms, being a clear example of biogenic habitats. Here, we demonstrate how pollination may boost ecosystem engineering using an illustrative case study based on a specialized interaction between a bee and an orchid with characteristic capsular fruits. We demonstrate that the orchid is fully dependent on the pollinator to set fruits. Post-dispersal fruits are voluminous ..., ,