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bioRxiv · 10.64898/2026.02.11.705334

Latitudinal dependence of stability trends in marine plankton in the Cenozoic

Morrison, M. L.·Woodhouse, A.·Swain, A.
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Abstract

The temporal stability and spatial heterogeneity of global marine ecosystems under changing climates reveal how biodiversity persists or collapses. However, the deep-time evolution of these phenomena remains poorly understood. We reconstructed the stability landscape of pelagic plankton from the Cretaceous-Paleogene extinction to the present. We find that the Cenozoic was a period of punctuated volatility with high turnover post-extinction and during the Late Neogene cooling. Spatially resolved analysis revealed latitude-dependent trends: equatorial regions stabilized over time, whereas polar communities, especially in the Southern Ocean, destabilized. Equatorial regions homogenized from initially high heterogeneity, whereas polar communities showed the opposite pattern, including a latitudinal seesaw of spatial heterogeneity over the past 30 million years. These findings illuminate temporal stability and spatial heterogeneity dynamics across geologic timescales.

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Morrison, M. L., Woodhouse, A., Swain, A.. 2026-02-12. Latitudinal dependence of stability trends in marine plankton in the Cenozoic. https://doi.org/10.64898/2026.02.11.705334

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