Global environmental predictors of benthic marine biogeographic structure

Abstract

Analyses of how environmental factors influence the biogeographic structure of biotas are essential for understanding the processes underlying global diversity patterns and for predicting large-scale biotic responses to global change. Here we show that the large-scale geographic structure of shallow-marine benthic faunas, defined by existing biogeographic schemes, can be predicted with 89-100% accuracy by a few readily available oceanographic variables; temperature alone can predict 53-99% of the present-day structure along coastlines. The same set of variables is also strongly correlated with spatial changes in species compositions of bivalves, a major component of the benthic marine biota, at the 1°grid-cell resolution. These analyses demonstrate the central role of coastal oceanography in structuring benthic marine biogeography and suggest that a few environmental variables may be sufficient to model the response of marine biogeographic structure to past and future changes in climate.bivalves | climate | macroecology | sea-surface temperature B iogeographic units (BUs), such as provinces or biomes, have been essential for understanding the macroecological and evolutionary processes underlying global biodiversity patterns (1-4) and are increasingly being incorporated in conservation planning (5-8). BUs are also becoming important from a global change perspective as components in models of biotic responses to global climate change in terrestrial settings (9). However, the factors that determine the biogeographic structure of benthic marine species in shallow-water habitats, where marine biodiversity is best documented and environmental changes are projected to be most severe (10-12), remain poorly understood, limiting our ability to model systems-level responses of marine biodiversity to environmental change. Here we use global datasets (Datasets S1, S2, S3, S4, and S5) to show that, in contrast to the more complex relationship between species richness and environment (13,14), the biogeographic structure of coastal and continental shelf habitats can be predicted using just a few oceanographic parameters. This robust first-order link between specific environmental factors and large-scale biotic patterns establishes the importance of climate and oceanography in structuring marine faunas and provides important insights into modeling past and future responses of marine biogeography to global change.We evaluate the correspondence between BUs and oceanographic variables using a model-fitting approach (Materials and Methods) to determine which oceanographic variables (individually or in combination) are most strongly correlated with biogeographic structure at both the ocean-basin and coastline scales (Table 1 and Tables S1 and S2). Our models focus on mean annual values and seasonal ranges of sea surface temperature, salinity, and productivity (hereafter TSP) because these variables have been previously hypothesized, separately or together, to affect taxonomic compositions and species richness in benthic marine system...

Faunal breaks and species composition of Indo-Pacific corals: the role of plate tectonics, environment and habitat distribution

“…Moreover, Spalding et al's [17] provinces were principally based on qualitative assessment of the global distribution of endemic species, whereas endemics are relatively uncommon among scleractinian coral faunas in most parts of the Indo-Pacific [56]. Other previous schemes differ more substantially from our own, classifying most of the Indo-Pacific as a single province [18,57]. These disparities point to the need for a more rigorous data-driven, quantitative approach to identifying large-scale marine zones or biogeographical provinces, such as that presented here.…”

“…changes in species identities as well as species richness over geographical space) [1,7]. Marine biogeographical zones have been recognized in previous work as reflecting changes in species composition [17,18]. However, delineation of these zones has tended to be subjective, and few of these earlier studies have focused on the potential reasons for such large-scale changes across faunal boundaries.…”

Biogeographic and bathymetric determinants of brachiopod extinction and survival during the Late Ordovician mass extinction

“…The unusual importance of palaeolatitudinal range in the latest Katian implies that changing sea surface temperatures played a major role in driving extinctions. Latitudinal ranges are closely linked to thermal tolerance ranges among extant aquatic ectotherms [51][52][53], and sea surface temperatures are the single most important determinant of biogeographic structure in the coastal oceans [54,55]. The thermal tolerance ranges of some extant marine invertebrate species have been conserved on million-year time scales [56], and many species shifted their ranges in response to Caenozoic and Quaternary climate changes [55,57,58].…”

Convergence, divergence, and parallelism in marine biodiversity trends: Integrating present-day and fossil data

“…The coasts show different, albeit nearly monotonic, sea surface temperature (SST) trends with latitude ( Fig. S1B), and, given the significant temperature−diversity correlations reported for bivalves and other marine groups (9,12,21), we might expect to find predictable differences in diversity along the two coasts. However, the diversity differences at a given latitude are complex (Fig.…”