Ontogenetic diversity buffers communities against consequences of species loss

Goals: The main goal of this study is to examine how ontogenetic diversity within species interacts with species diversity and whether diversity within species can buffer against loss of species diversity. The experiment has 9 treatments manipulating size diversity (M = medium stage vs SML = very wide stage range) of 3 focal predator species. Species are either alone (single species)(A,B,C) or all three combined (ABC) in an additive design. The density of each focal predator is constant acrosss species, size & diversity treatment. Biomass is similar across size treatments, and comparable across species (within natural limits of their morphology). General setup and data: The data are from a mesocosm experiment that was carried in from July 12th to August 11th 2016, at the South Campus Research Facility of Rice University, Houston, TX. A complete description of the methods are given in the corresonding manuscript. Briefly, experiments were carried out in 300L PVC cylindrical mesocosm with 60% shade cloth filled with declorinated water. We set up 60 mesocosm in an open field outdors in complete randomized block design. We then added several tadpole species, and concentrated zooplankton from local ponds. Finally, we factorially manipulated the size structure and presence absence of three focal invertebrate predators to examine effects on tadpole, invertebrate, and zooplankton community. Data includes: Experimental design Final focal predator abundance and mass following final take down. Final Invertebrate dry mass and species counts following final take down. Metamorph mass & emergence date collected daily Final total tadpole dry mass for two amphibian species at final take down. Zooplankton abundance by species based on subsamples obtained with depth integrated tube samplers. Periphyton density based on Chlorophyll a concentration extracted from glass slides Phytoplankton density based on InVivo measurements. Dissolve oxygem concentration and mg/L sampled three times consecutely at sunrise 7:10-8:30am (s1), sunset 7:40-8:20pm (s2) and sunrise , 7:10-7:40am (s3) on August 8-August 9th.