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ABSTRACT AimBiological diversity is shaped by processes occurring at different spatial and temporal scales. However, the direct influence of the spatial and temporal scale on patterns of occupancy is still understudied. Today, occupancy is often negatively correlated with species richness, but it is unknown whether this relationship is scale dependent and consistent through time. Here, we use datasets of contemporary and paleontological communities to explore the occupancy‐richness relationship across space and time, examining how scale influences this relationship. LocationVarying spatial extents with global coverage. TimeVaries from 7 mya to 2021 CE. Taxaforaminifera, mammals, birds, fish, and plants. MethodsWe gathered datasets spanning different spatial, temporal, and taxonomic extents. We binned each dataset into distinct time periods and spatially subsampled them into regional pools of varying sizes. We calculated regional occupancy and richness for each pool, measuring the strength of the relationship between the two. Using linear mixed models, we related the occupancy‐richness relationship to the size of the regional pools, overall species richness, and climatic changes through time. ResultsWe observed nearly ubiquitous negative occupancy‐richness relationships across taxa, spatial scale, and time. The size of the regional pools and time bins had no consistent effects on the strength of the relationship, but the strength of the negative relationship varied substantially among taxa, with foraminifera and North American pollen showing weaker relationships than mammals and birds. Changes in this relationship through time were not driven by climatic perturbations but by the species richness observed across all regional pools. ConclusionsPatterns of regional richness and occupancy are consistently negatively related and independent of spatial and temporal scale and of direct climatic changes. However, differences in the ecology of species (e.g., dispersal ability) and changes in biodiversity and community composition through time may cause fluctuations in the strength of the occupancy‐richness relationship.
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Weak but consistent abundance–occupancy relationships across taxa, space and time
Abstract AimAbundance–occupancy relationships posit that more locally abundant species occupy more sites than less abundant species. Although widely supported, the occurrence and detection of abundance–occupancy relationships is sensitive to sampling and detection processes. Data from large‐scale standardized sampling efforts are key to address abundance–occupancy relationships. We aimed to use such a dataset to evaluate the occurrence of abundance–occupancy relationships across different spatial grains and over time for aquatic and terrestrial taxa. LocationUSA. Time period2014–2019. Major taxa studiedBirds, mammals, beetles, ticks, fishes, macroinvertebrates and zooplankton. MethodsSpecies abundance and occupancy data were obtained from the National Ecological Observatory Network (NEON). Species mean abundance and occupancy (fraction of sampled locations that were occupied) were estimated for three different spatial grains (i.e., plot, site and domain) for all years sampled. Linear models were used to explore the consistency of interspecific abundance–occupancy relationships. The slope coefficients of these models were related to temporal and spatial variables and to species richness while controlling for taxa in a linear mixed‐effects model (LMM) framework. ResultsWe found evidence for positive abundance–occupancy relationships across the three spatial grains and over time for all taxa we studied. However, our linear models had low explanatory power, suggesting that relationships, although general, were weak. Abundance–occupancy relationships were slightly stronger at the smallest spatial grain than at the largest spatial grain, but showed no detectable change over time for any taxa. Finally, species richness was not associated with the strength of these relationships. Main conclusionsTogether, our results suggest that positive interspecific abundance–occupancy relationships are fairly general but are not capable of explaining substantial variation in spatial patterns of abundance, and that other factors, such as species traits and niche, are also likely to influence these relationships.
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- Award ID(s):
- 2213878
- PAR ID:
- 10367637
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Global Ecology and Biogeography
- Volume:
- 31
- Issue:
- 5
- ISSN:
- 1466-822X
- Format(s):
- Medium: X Size: p. 968-977
- Size(s):
- p. 968-977
- Sponsoring Org:
- National Science Foundation
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