Late Proterozoic Transitions in Climate, Oxygen, and Tectonics, and the Rise of Complex Life

Planavsky, Noah J.; Tarhan, Lidya G.; Bellefroid, Éric; Evans, David A.D.; Reinhard, Christopher T.; Love, Gordon D.; Lyons, Timothy W.

doi:10.1017/s1089332600002965

Cited by 18 publications

(17 citation statements)

References 226 publications

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“…Around 800 million years ago (Ma) there is evidence for a marked increase in carbon isotope variability, the onset of Neoproterozoic oxygenation, and a marked increase in biological innovation (Cole et al, ; Halverson et al, ; Planavsky et al, ; Thomson et al, ; Turner & Bekker, ). Numerous workers have proposed that these shifts record the onset of a more dynamic global carbon cycle (e.g., Bjerrum & Canfield, ).…”

Section: Introductionmentioning

confidence: 99%

Making Sense of Massive Carbon Isotope Excursions With an Inverse Carbon Cycle Model

et al. 2018

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The beginning and end of the Proterozoic Eon are marked by extreme variations in carbonate carbon isotope values that have been interpreted to record massive perturbations to the global carbon cycle. The lower Proterozoic contains an extended interval of strata characterized by positive carbonate δ13C values. Conversely, uppermost Proterozoic carbonate strata contain thick intervals with extremely negative δ13C values and multiple large swings in carbonate δ13C. Previous attempts to model these pronounced carbon isotope excursions as shifts in the global marine dissolved inorganic carbon (DIC) reservoir have proved to be problematic, as the direction and magnitude of these positive and negative carbon isotope excursions require unrealistic amounts of either organic carbon burial or organic carbon oxidation, respectively. Here we present a modified global carbon cycle model—coupled with oxygen and sulfur cycle mass balances—that includes a parameterization of the recycling of sedimentary isotope anomalies and allows the extent of organic carbon oxidation to vary as a function of atmospheric oxygen levels. Our model is designed to match carbon isotope records while maintaining redox and mass balance with a given set of initial conditions and carbon cycle parameterizations. Using this approach, we demonstrate that there is a range of plausible biogeochemical perturbations that could induce substantial δ13C excursions in the global marine DIC reservoir. However, we also find that there are multiple, nonunique Earth system states for any observed marine δ13C value.

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Section: Introductionmentioning

confidence: 99%

Making Sense of Massive Carbon Isotope Excursions With an Inverse Carbon Cycle Model

et al. 2018

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“…Note, that the difference between the two subsets with-and without icehouse intervals of the pre-Ediacaran data-set is only marginal (Figure 1), and might even suggest larger 13 C bed−to−bed at intermediate stratigraphic scales for the latter subset. Evidence for cold climatic stages and possible transitions to more invigorated ocean turnover in the Mesoproterozoic, Ediacaran and Permian-Triassic are ambiguous, and are generally viewed as warm intervals (Wignall and Twitchett, 1996;Evans, 2000;Planavsky et al, 2015). So, while a possible DOC-driven broadening of the 13 C bed−to−bed spectrum cannot be completely ruled out, it is unlikely within the current state of knowledge.…”

Section: Non-steady State Dynamics and Carbon Isotope Variationsmentioning

confidence: 97%

Increased Stability in Carbon Isotope Records Reflects Emerging Complexity of the Biosphere

Schobben

Schootbrugge

2019

Front. Earth Sci.

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Preference for certain stable isotopes (isotope fractionation) during enzyme-mediated reactions is a universal aspect of life. For instance, carbon isotopes are fractionated during anabolic (e.g., photosynthate production) and catabolic (e.g., methanogenesis) reactions. These biological processes exert a major control on ambient micro-scale chemical conditions as well as the large-scale exogenic carbon reservoir. Combined with the ubiquity of bio-mediated carbonate mineral nucleation and obligate enzymatic skeletonization, these biochemical reactions and their control on the exogenic carbon pool are known to leave distinct imprints on carbonate minerals which accumulate as sediments throughout Earth's history. Here, we study the evolution of the marine carbonate-carbon isotope record based on database compilations from the Precambrian and the Phanerozoic. By looking at the frequency distribution of the amplitude of stratigraphic variation at various temporal resolutions, we assess trends in the carbonate-carbon isotope variability. Part of this variation can only be explained by authigenic and diagenetic carbonate mineral additions, which carry metabolic carbon isotope signatures created in the vicinity of cells and secluded (sub-)seafloor micro-environments. It can be envisioned that compartmentalization (membrane enclosed regions), the accumulation of extracellular polymeric substances (biofilms), and restricted fluid exchange in the early diagenetic environment can create sharp isotope gradients that lead to a high-order of micro-scale carbon isotope variability being imprinted in carbonate rock. The frequency of the high-amplitude variation diminishes with the development of more complex life (metazoan-dominated biosphere); presumably through the dispersing action of bioturbation (eradicating these micro-environments), increased grazing pressure and the advent of obligate biomineralization. On the other hand, stark chemical gradients in a world dominated by unicellular life (prokaryotes and to a lesser extent eukaryotes) are thought to leave a distinctly more variable C isotope signature in carbonate rock. An enhanced understanding of the biogenicity of carbonate carbon isotope signatures at multiple spatial and temporal scales provides a baseline that is usable in the search for signs of (past) extraterrestrial life.

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“…It is noteworthy that the low oxygen levels in the Paleoproterozoic (2500 to 1600 Mya ago) were incompatible with the bioavailability of essential micronutrients for the enzymatic activity of eukaryotic cell [5,6]. In addition to having low levels of micronutrients, the Paleoproterozoic oceans also had high sulfate concentrations [61,62,63].…”

Section: Primary Plastid Endosymbiosismentioning

confidence: 99%

“…Later, four more oxygenation events happened in the primitive Earth. In the Proterozoic from 1850 to 850 Mya, the oceans became slightly less anoxic and sulfidic [5,6,7,8]. These environmental changes appear to have triggered an increase in Proterozoic biodiversity, even from the complex eukaryotes carrying specialized structures [6,8].…”

Section: Introductionmentioning

confidence: 99%

A Timescale for the Radiation of Photosynthetic Eukaryotes

Evanovich¹,

Guerreiro²

2020

Preprint

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Oxygenic photosynthesis is considered the most important evolutionary innovation in the history of Earth. It depends on two photosystems, responsible for the photolysis of water and the reduction of carbon dioxide. Oxygen and carbohydrates are released at the end of the reaction. Extraordinary, the oxygen released created the stratospheric ozone layer, and transformed the ocean chemistry, whereas the carbohydrates are the primary source of energy for complex cells. Several lines of evidence indicate the photosynthesis arose in the ancestors of cyanobacteria. It was spread over some eukaryotes by the acquisition of a freeliving cyanobacterium, which evolved into photosynthetic plastid, the chloroplast. The timing of the chloroplast emergence is still controversy.Estimated ages range from 600 to 2100 million years ago (Mya) in accordance to previous studies.The aim of this study is to clarify several aspects of the origin and diversification of photosynthetic eukaryotes. For this purpose, we utilized a data set based on 27 proteincoding genes from genomes of cyanobacteria and photosynthetic eukaryotes, more genes than other papers that also utilized plastid genes, and performed the Bayesian analysis method to estimate the divergence times of the photosynthetic eukaryotes. Results showed photosynthetic eukaryotes emerged Late Mesoproterozoic about 1342 Mya. The Early Proterozoic oceans did not have adequate conditions for eukaryotes, because chemical elements such as zinc and molybdenum were at reduced concentrations, and they are essential to the formation of eukaryotic proteins.

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Late Proterozoic Transitions in Climate, Oxygen, and Tectonics, and the Rise of Complex Life

Cited by 18 publications

References 226 publications

Making Sense of Massive Carbon Isotope Excursions With an Inverse Carbon Cycle Model

Making Sense of Massive Carbon Isotope Excursions With an Inverse Carbon Cycle Model

Increased Stability in Carbon Isotope Records Reflects Emerging Complexity of the Biosphere

A Timescale for the Radiation of Photosynthetic Eukaryotes

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