175-4 Evolutionary Patterns of Proterozoic Eukaryotes

Session: The Neoproterozoic Earth and Life Co-evolution, Part I

Presenting Author:

Shuhai Xiao

Authors:

Xiao, Shuhai¹, Tang, Qing², Zheng, Wentao³, Zhang, Shuhan⁴, Fan, Junxuan⁵, Riedman, Leigh Anne⁶, Hou, Xudong⁷, Muscente, A. Drew⁸, Bykova, Natalia⁹, Sadler, Peter M.¹⁰, Wang, Xiangdong¹¹, Zhang, Feifei¹², Yuan, Xunlai¹³, Zhou, Chuanming¹⁴, Wan, Bin¹⁵

(1) Virginia Tech, BLACKSBURG, VA, USA, (2) School of Earth Sciences and Engineering, Nanjing University, Nanjing, China, (3) Earth Science, University of California at Santa Barbara, Santa Barbara, CA, USA, (4) School of Earth Sciences and Engineering, Nanjing University, Nanjing, China, (5) School of Earth Sciences and Engineering, Nanjing University, Nanjing, China, (6) Department of Earth Science, University of California Santa Barbara, Santa Barbara, CA, USA, (7) School of Earth Sciences and Engineering, Nanjing University, Nanjing, China, (8) Princeton Consultants, Princeton, NJ, USA, (9) Department of Geological Sciences, University of Missouri, Columbia, Mo, USA, (10) Department of Earth and Planetary Sciences, University of California Riverside, Riverside, CA, USA, (11) School of Earth Sciences and Engineering, Nanjing University, Nanjing, China, (12) School of Earth Sciences and Engineering, Nanjing University, Nanjing, China, (13) Nanjing Institute Geology and Paleontology, Nanjing, China, (14) Nanjing Institute of Geology and Palaeontology, Nanjing, Jiangsu, China, (15) Nanjing Institute of Geology and Paleontology, Nanjing, Jiangsu, China, (16) Nanjing Institute Geology Paleontology, Nanjing, Jiangsu, China, (17) Nanjing Institute of Geology and Paleontology, Nanjing, Jiangsu, China, (18) Department of Earth Sciences, University of Hong Kong, Hong Kong, China, (19) Department of Earth Sciences, University Hong Kong, Hong Kong, China, (20) School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu, China,

Abstract:

The fossil record provides key data for the assessment of the evolutionary patterns and dynamics of biodiversity in the geological past, but attempts to analyze the Proterozoic paleontological database have been limited in scope. In this presentation, we will summarize the results from a comprehensive analysis of Proterozoic eukaryote fossils using the CONOP algorithm. Eukaryote fossils first appeared in the Paleoproterozoic, concurrently with or shortly after the Great Oxidation Event. For much of the Mesoproterozoic and early Neoproterozoic, the diversity of eukaryote fossils increased slowly and remained at a relatively low level. However, it is during this time interval when crown-group eukaryotes first appeared in the fossil record and several major eukaryote clades diverged, including the Archaeplastida (e.g., green and red algae), Opisthokonta (e.g., fungi), Harosa (e.g., rhizarians and stramenopiles), and Amoebozoa. Despite their early divergences, these eukaryotes apparently left a limited ecological footprint in the Earth-life system. The subsequent Cryogenian Period represents a major divide in eukaryote evolution. Post-Cryogenian eukaryote fossil diversity rose rapidly and featured major diversification and extinction events in the Ediacaran Period. The currently available and emerging data from paleontology, phylogenomics, and geochemistry allow us to establish a holistic understanding of and to formulate hypotheses about the interactions between life and Earth during the Proterozoic eon – a formative age in the history of our planet.

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-8812

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