Hierarchical drivers of cryptic biodiversity on coral reefs

Declines in habitat structural complexity have marked ecological outcomes, as currently observed in many of the world’s ecosystems. Coral reefs have provided a model for such changes in marine ecosystems, but our understanding has been centred on corals and fishes at broad spatial scales when metazoan diversity on coral reefs is dominated by small cryptic taxa (herein: ‘cryptofauna’). Given the paucity of studies and high taxonomic complexity of the cryptofauna, both of which limit a priori hypotheses, we asked whether hierarchical structuring theory provides a compelling framework to impose order and quantify pattern. In general terms, we explored whether cryptic communities are sufficiently described by broad seascape parameters or limited by a set of processes operating at their distinctly nested microhabitat scale. To address this theory and gaps in knowledge for the cryptofauna, we characterised community structure in coral rubble, an eroded coral condition where biodiversity proli..., Overarching aim and design: This study was designed to investigate whether the theory of hierarchical structuring of ecological systems could explain resource aggregation in coral rubble where biodiversity proliferates. Data were analysed across multiple scales of ecological organisation; first at the level of seascape drivers and then at the level of microhabitat.
At the seascape scale, water depth and hydrodynamic exposure represented higher-order environmental limits on rubble patches. Whether these seascape parameters sufficiently explained lower-level entities within rubble was assessed independently using permutational multivariate analysis of variance (PERMANOVA) on (1) rubble piece morphology, (2) the proportional cover of sessile taxa on rubble pieces, and motile cryptofauna (3) density, (4) diversity and (5) size spectra. Separate Excel spreadsheets are attached for each of these five datasets.
To determine the applicability of hierarchical theory to rubble biomes more acutely..., Microsoft Excel is required to open the data files. No novel code was used.