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Past and future decline of tropical pelagic biodiversity


Yasuhara, Moriaki et al. (2020), Past and future decline of tropical pelagic biodiversity, Dryad, Dataset,


A major research question concerning global pelagic biodiversity remains unanswered: when did the apparent tropical biodiversity depression (i.e., bimodality of latitudinal diversity gradient [LDG]) begin? The bimodal LDG may be a consequence of recent ocean warming or of deep-time evolutionary speciation and extinction processes. Using rich time-slice datasets of planktonic foraminifers, we show here that a unimodal (or only weakly bimodal) diversity gradient, with a plateau in the tropics, occurred during the last ice age and has since then developed into a bimodal gradient through species distribution shifts driven by postglacial ocean warming. The bimodal LDG likely emerged before the Anthropocene (here defined as ∼1950) and perhaps ∼15,000 y ago, indicating a strong environmental control of tropical diversity even before the start of anthropogenic warming. However, our model projections suggest future anthropogenic warming further diminishes tropical pelagic diversity to a level not seen in millions of years.

Usage Notes

Raw data for Figs 1–4.


Research Grants Council, University Grants Committee, Award: HKU 17302518

Ministry of Science Technology Taiwan, Award: MOST 108-2611-M-002-001

Deutsche Forschungsgemeinschaft, Award: KI 806/16-1,FOR 2332

Seed Funding Programme for Basic Research of the University of Hong Kong, Award: 2.01611E+11

Program for Advancing Strategic International Networks to Accelerate the Circulation of Talented Researchers, the Japan Society for the Promotion of Science, Award: NA

Jarislowsky Foundation, Award: NA