Articles | Volume 45, issue 1
https://doi.org/10.5194/jm-45-159-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/jm-45-159-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Early Eocene evolutionary trajectories within the Toweius genus: insights from a newly identified species in the equatorial Atlantic
Department of Earth Sciences, Uppsala University, Uppsala, Sweden
Jorijntje Henderiks
Department of Earth Sciences, Uppsala University, Uppsala, Sweden
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Boris-Theofanis Karatsolis and Jorijntje Henderiks
Clim. Past, 19, 765–786, https://doi.org/10.5194/cp-19-765-2023, https://doi.org/10.5194/cp-19-765-2023, 2023
Short summary
Short summary
Ocean circulation around NW Australia plays a key role in regulating the climate in the area and is characterised by seasonal variations in the activity of a major boundary current named the Leeuwin Current. By investigating nannofossils found in sediment cores recovered from the NW Australian shelf, we reconstructed ocean circulation in the warmer-than-present world from 6 to 3.5 Ma, as mirrored by long-term changes in stratification and nutrient availability.
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Short summary
Toweius was among the most widespread and important calcareous nannoplankton groups in the oceans 53 million years ago, playing a key role in the evolutionary transition to another prominent group during the Cenozoic (Reticulofenestra). Using detailed biometric measurements with high-resolution imaging, we describe a distinctive, smaller morphotype of Toweius. Our results indicate that this form evolved gradually through speciation, shedding light on the complex evolutionary dynamics of Toweius.
Toweius was among the most widespread and important calcareous nannoplankton groups in the...