Brachiopod diversity gradient
The latitudinal diversity gradient is one of the most extensive and important biodiversity patterns on the Earth. The analysis of the global latitudinal diversity patterns of living brachiopods showed a consistent bimodal pattern dominated by two mid-latitude peaks at warm-temperate zones what is in contradiction to the classical unimodal latitudinal diversity gradient. This bimodal pattern of living brachiopods is not affected by taxonomic, bathymetric and spatial scales. We tested several ecological hypotheses to explain such pattern and the Rapoport’s rule was found to be the best fitting the bimodal pattern.
Figure: (a) Latitudinal diversity gradient of living brachiopods vs. mean latitudinal range of brachiopods in 20° latitudinal bins. (b) Latitudinal diversity gradient of living brachiopods vs. mean sea surface temperature.