Population fragmentation, florivory, and the effects of flower morphologyalterations on the pollination success of Myrmecophila tibicinis(Orchidaceae)

摘要

Plant-animal interactions are an active field in ecological research because of its relevance to population dynamics, community ecology, and evolution. Furthermore, it is important to conservation biology because of the sensitivity of interactions to human alteration of ecosystems (Saunders et al. 1991, Hunter 1996, Thompson 1996). Habitat fragmentation directly leads to the modification of environmental conditions and to changes in the composition and structure of communities. Such alterations are later manifested in functional changes of the ecosystems that spread through the webs of interspecific interactions (Jennersten 1988). The functional integrity of habitat remnants may fail and some species could be driven to extinction by the collapse of the interactions upon which they rely. Given the extent of fragmentation in tropical habitats and the relevance of interspecific interactions in them, studies on the effects of fragmentation on interaction webs in the tropics are clearly needed (Terborgh 1992). The effects of habitat fragmentation on insect-plant interactions, however, are little known, and information is very unbalanced among interaction types. Studies on insects in fragmented habitats have focused mainly on pollinators, seed predators, and decomposers; little is known about herbivory (Didham et al. 1996), and to our knowledge, nothing is known about the effects of habitat fragmentation on fiorivory.