Tyler Carrie L, Kowalewski Michał
Department of Geology and Environmental Earth Sciences, Miami University, 250 S. Patterson Avenue, Oxford, OH 45056, USA
Florida Museum of Natural History, University of Florida, 1659 Museum Road, PO Box 117800, Gainesville, FL 32611-7800, USA.
Proc Biol Sci. 2017 Mar 15;284(1850). doi: 10.1098/rspb.2016.2839.
Rigorous documentation of spatial heterogeneity (β-diversity) in present-day and preindustrial ecosystems is required to assess how marine communities respond to environmental and anthropogenic drivers. However, the overwhelming majority of contemporary and palaeontological assessments have centred on single higher taxa. To evaluate the validity of single taxa as community surrogates and palaeontological proxies, we compared macrobenthic communities and sympatric death assemblages at 52 localities in Onslow Bay (NC, USA). Compositional heterogeneity did not differ significantly across datasets based on live molluscs, live non-molluscs, and all live organisms. Death assemblages were less heterogeneous spatially, likely reflecting homogenization by time-averaging. Nevertheless, live and dead datasets were greater than 80% congruent in pairwise comparisons to the literature estimates of β-diversity in other marine ecosystems, yielded concordant bathymetric gradients, and produced nearly identical ordinations consistently delineating habitats. Congruent estimates from molluscs and non-molluscs suggest that single groups can serve as reliable community proxies. High spatial fidelity of death assemblages supports the emerging paradigm of Conservation Palaeobiology. Integrated analyses of ecological and palaeontological data based on surrogate taxa can quantify anthropogenic changes in marine ecosystems and advance our understanding of spatial and temporal aspects of biodiversity.
要评估海洋群落如何应对环境和人为驱动因素，需要对现代和工业化前生态系统中的空间异质性（β多样性）进行严格记录。然而，绝大多数当代和古生物学评估都集中在单一的高等分类群上。为了评估单一分类群作为群落替代物和古生物学代理的有效性，我们比较了美国北卡罗来纳州昂斯洛湾52个地点的大型底栖生物群落和同域死亡组合。基于活的软体动物、活的非软体动物和所有活的生物的数据集，其组成异质性没有显著差异。死亡组合在空间上的异质性较小，这可能反映了时间平均导致的同质化。尽管如此，在与其他海洋生态系统中β多样性的文献估计值进行成对比较时，活的和死的数据集一致性超过80%，产生了一致的深度梯度，并产生了几乎相同的排序结果，始终能够描绘出栖息地。软体动物和非软体动物的一致估计表明，单个类群可以作为可靠的群落代理。死亡组合的高空间保真度支持了保护古生物学这一新兴范式。基于替代分类群对生态和古生物学数据进行综合分析，可以量化海洋生态系统中的人为变化，并增进我们对生物多样性时空方面的理解。
