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Climate change is threatening tropical reefs across the world, with most scientists agreeing that the current changes in climate conditions are occurring at a much faster rate than in the past and are potentially beyond the capacity of reefs to adapt and recover. Current research in tropical ecosystems focuses largely on corals and fishes, although other benthic marine invertebrates provide crucial services to reef systems, with roles in nutrient cycling, water quality regulation, and herbivory. We review available information on the effects of environmental conditions associated with climate change on noncoral tropical benthic invertebrates, including inferences from modern and fossil records. Increasing sea surface temperatures may decrease survivorship and increase the developmental rate, as well as alter the timing of gonad development, spawning, and food availability. The broad latitudinal distribution and associated temperature ranges of several pantropical taxa suggest that some reef communities may have an in-built adaptive capacity. Tropical benthic invertebrates will also show species-specific sublethal and lethal responses to sea-level rise, ocean acidification, physical disturbance, runoff, turbidity, sedimentation, and changes in ocean circulation. In order to accurately predict a species' response to these stressors, we must consider the magnitude and duration of exposure to each stressor, as well as the physiology, mobility, and habitat requirements of the species. Stressors will not act independently, and many organisms will be exposed to multiple stressors concurrently, including anthropogenic stressors. Environmental changes associated with climate change are linked to larger ecological processes, including changes in larval dispersal and recruitment success, shifts in community structure and range extensions, and the establishment and spread of invasive species. Loss of some species will trigger economic losses and negative effects on ecosystem function. Our review is intended to create a framework with which to predict the vulnerability of benthic invertebrates to the stressors associated with climate change, as well as their adaptive capacity. We anticipate that this review will assist scientists, managers, and policy-makers to better develop and implement regional research and management strategies, based on observed and predicted changes in environmental conditions.

Carbonate skeletons of hermatypic corals harbor diverse populations of microboring organisms. The assemblages of euendohthic (boring) algae and cyanobactena inhabiting the corallum of hve corals are different from those that colonize dead and denuded coral skeletons. The species composition of endoliths in live corals is a result of a selection in favor of ohgophotic, positively phototropic, fast-growing taxa which can cope with the accretion rates of coral skeleton. Following the death and denudation of corals, the bioerosion of their skeletons changed profoundly with respect to (1) species composition of dominant endolithic microorganisms, (2) their boring patterns and (3) the direction of microbormg activity. Skeletons of live colonies of Pontes lobata were bored from the inside outward by the siphonalean chlorophyte Ostreobim quekettii. Dead and denuded parts of coral skeleton were colonized at the surface and bored inward by a succession of euendoliths, starting with colonization of the short-lived opportunistic pioneer endolith Phaeophila dendroides (Chlorophyta), followed by Mastigocoleus t e s t a r m and Plectonema terebrans (cyanobacteria), to establish within 2 yr a stable 0. queketto-dominated endolith community. The sequence of colonization and successional changes was determined usmg experimentally exposed carbonate substrates. During the life of the coral, the endoliths are protected from grazers. Their bioerosive activity keeps pace with the rate of coral accretion but avoids the skeletal surface adjacent to the coral tissue. The green bands formed by endohths within the skeleton of live corals bear relevance to sclerochronological interpretations. Their formation reflects either variation m coral growth rates or algal seasonality, but most likely a combination of both. Endoliths in dead coral skeletons are exposed to grazing by mollusks, echinoderms and scarid fish, which significantly increases overall bioerosion rates. In the absence of intensive grazing, dead parts of coral skeleton are overgrown by epilithic algal turf. The series of successional biological changes tnggered by the death and denudation of corals shifts the ecological balance between constructive and destructive forces on a coral reef in favor of the latter.