title: Bromeliad-living spiders improve host plant nutrition and growth.
abstract: Although bromeliads are believed to obtain nutrients from debris deposited by animals in their rosettes, there is little evidence to support this assumption. Using stable isotope methods, we found that the Neotropical jumping spider Psecas chapoda (Salticidae), which lives strictly associated with the terrestrial bromeliad Bromelia balansae, contributed 18% of the total nitrogen of its host plant in a greenhouse experiment. In a one-year field experiment, plants with spiders produced leaves 15% longer than plants from which the spiders were excluded. This is the first study to show nutrient provisioning in a spider-plant system. Because several animal species live strictly associated with bromeliad rosettes, this type of facultative mutualism involving the Bromeliaceae may be more common than previously thought.
authors: Departamento de Zoologia, Instituto de Biologia, Universidade Estadual de Campinas, CP 6109, CEP 13083-970, Campinas, São Paulo, Brazil. gq_romero@yahoo.com.br
authors: Gustavo Q
authors: GQ
authors: Romero
authors: Paulo
authors: P
authors: Mazzafera
authors: Joao
authors: J
authors: Vasconcellos-Neto
authors: Paulo C O
authors: PC
authors: Trivelin