Kurzgesagt – In a Nutshell
Kurzgesagt – In a Nutshell
Embedded Files
Sources – Broken Time Machine
Sources – Broken Time Machine
We thank the following expert for his input and critical reading:
Prof. Jochen J. Brocks
Professor of Geobiology, Research School of Earth Sciences, The Australian National University (Canberra)
—It feels like you stepped into an oven. There are no plants or any vegetation, and almost no moisture in the air.
The global mean surface temperature (GMST) and global average temperature (GAT) 250 million years ago was up to 30°C, twice as high as today.
#Judd, J. E. et al. (2024): A 485-million-year history of Earth’s surface temperature. Science, Vol. 385 (6715)
#Scotese, C. R. et al. (2021): Phanerozoic paleotemperatures: The earth’s changing climate during the last 540 million years. Earth-Science Reviews, Vol. 215
https://www.sciencedirect.com/science/article/abs/pii/S0012825221000027
#Nowak, H. (2020): Palaeophytogeographical Patterns Across the Permian–Triassic Boundary, Frontiers in Earth Science, Vol. 8
https://www.frontiersin.org/journals/earth-science/articles/10.3389/feart.2020.613350/full
Quote: “The subtropical desert biome (biome 3: coastal and inland tropical desert biome of Ziegler, 1990) is characterized by a water deficit during every month of the year. The vegetation is generally scarce and the plants that do occur are adapted for survival rather than competition. The vegetation is dominated by xerophytes and succulents that can persist in a continuously dry environment. Large flat root systems are specialised to gather moisture; leaf sizes are reduced to avoid desiccation. The preservation potential of these plants is exceptionally low. Sedimentary indicators are evaporites and aeolian sands.”
#Abrantes Jr., F. R. et al. (2019): Register of increasing continentalization and palaeoenvironmental changes in the west-central pangaea during the Permian-Triassic, Parnaíba Basin, Northern Brazil. Journal of South American Earth Sciences
Vol. 93
https://www.sciencedirect.com/science/article/abs/pii/S0895981118304127?via%3Dihub
Quote: “The Permian-Triassic interval (298 to 201 million of years) was marked by one of the largest collages of Earth continental blocks, forming through collisional events, the assembly of Pangaea supercontinent (Van der Voo et al., 1984; Crowley et al., 1989; Van der Voo, 1993; Scotese & Langford, 1995; Scotese et al., 1999).
(...)
Pangea continentalization and climatic changes propitiated the development of extensive arid areas and red beds in the tropical zones which attest highly oxidizing environments in acid-saline lake systems surrounded by aeolian-dominated areas (Parrish et al., 1986; Benison et al., 1998; Scotese et al., 1999; Benison & Goldstein, 2001; Zharkov & Chumakov, 2001; Andeskie et al., 2018). During the Permian-Triassic period, these continental saline environments extended regionally in the north of equatorial Pangaea, compound a stark red landscape of acidic lakes in an arid climate (Andeskie et al., 2018).”
#Preto, N. et al. (2010): Triassic climates — State of the art and perspectives. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 290
https://www.sciencedirect.com/science/article/abs/pii/S0031018210001434?via%3Dihub
Quote: “The palaeogeography of the Triassic is distinctive. All continents were merged into a single supercontinent, Pangaea, centred more or less on the equator, with exposed land extending from about 85°N to 90°S (Ziegler et al., 1983). The continent was surrounded by the Panthalassa Ocean, and a deep oceanic gulf, Tethys, cutting into the supercontinent (Fig. 1). This ocean was latitudinally confined to the tropical–subtropical belt between 30° North and 30° South (Ziegler et al., 2003). The concentration of exposed land at low and mid-latitudes, and the presence of a warm sea-way would have maximized summer heating in the circum-Tethyan part of the continent (e.g. Kutzbach and Gallimore, 1989; Dubiel et al., 1991). Furthermore, extreme continentality with hot summers and relatively cold winters, and a strong monsoonal circulation are expected (e.g. Robinson, 1973; Kutzbach and Gallimore, 1989). The climatic consequences of such a “mega-monsoon” are, according to Parrish (1993): 1) abundant, but extremely seasonal rainfall, concentrated during the summer in the northern hemisphere; 2) a relatively dry equatorial region in the eastern part of Pangaea, facing the western Tethys; and 3) breakdown of the zonal climate pattern.
#Nowak, H. et al. (2020): Palaeophytogeographical Patterns Across the Permian–Triassic Boundary. Frontiers in Earth Science, Vol. 8
#Scotese, C. (2001): Atlas of Earth History, Paleomap Project
—The sunlight smashing down from the cloudless and weirdly colored sky is reflected by an endless sea of red and orange sand dunes. They stretch over the horizons, for thousands of kilometers in every direction.
#Abrantes Jr., F. R. et al. (2019): Register of increasing continentalization and palaeoenvironmental changes in the west-central pangaea during the Permian-Triassic, Parnaíba Basin, Northern Brazil. Journal of South American Earth Sciences
Vol. 93
https://www.sciencedirect.com/science/article/abs/pii/S0895981118304127?via%3Dihub
Quote: “The Permian-Triassic interval (298 to 201 million of years) was marked by one of the largest collages of Earth continental blocks, forming through collisional events, the assembly of Pangaea supercontinent (Van der Voo et al., 1984; Crowley et al., 1989; Van der Voo, 1993; Scotese & Langford, 1995; Scotese et al., 1999).
(...)
Pangea continentalization and climatic changes propitiated the development of extensive arid areas and red beds in the tropical zones which attest highly oxidizing environments in acid-saline lake systems surrounded by aeolian-dominated areas (Parrish et al., 1986; Benison et al., 1998; Scotese et al., 1999; Benison & Goldstein, 2001; Zharkov & Chumakov, 2001; Andeskie et al., 2018). During the Permian-Triassic period, these continental saline environments extended regionally in the north of equatorial Pangaea, compound a stark red landscape of acidic lakes in an arid climate (Andeskie et al., 2018).”
#Preto, N. et al. (2010): Triassic climates — State of the art and perspectives. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 290
https://www.sciencedirect.com/science/article/abs/pii/S0031018210001434?via%3Dihub
Quote: “The palaeogeography of the Triassic is distinctive. All continents were merged into a single supercontinent, Pangaea, centred more or less on the equator, with exposed land extending from about 85°N to 90°S (Ziegler et al., 1983). The continent was surrounded by the Panthalassa Ocean, and a deep oceanic gulf, Tethys, cutting into the supercontinent (Fig. 1). This ocean was latitudinally confined to the tropical–subtropical belt between 30° North and 30° South (Ziegler et al., 2003). The concentration of exposed land at low and mid-latitudes, and the presence of a warm sea-way would have maximized summer heating in the circum-Tethyan part of the continent (e.g. Kutzbach and Gallimore, 1989; Dubiel et al., 1991). Furthermore, extreme continentality with hot summers and relatively cold winters, and a strong monsoonal circulation are expected (e.g. Robinson, 1973; Kutzbach and Gallimore, 1989). The climatic consequences of such a “mega-monsoon” are, according to Parrish (1993): 1) abundant, but extremely seasonal rainfall, concentrated during the summer in the northern hemisphere; 2) a relatively dry equatorial region in the eastern part of Pangaea, facing the western Tethys; and 3) breakdown of the zonal climate pattern.
#Britannica (2024): Triassic Period
https://www.britannica.com/science/Triassic-Period
Quote: “Beginning in the Late Permian and continuing into the Early Triassic, the emergence of the supercontinent Pangea and the associated reduction in the total area covered by continental shelf seas led to widespread aridity over most land areas. Judging from modern conditions, a single large landmass such as Pangea would be expected to experience an extreme, strongly seasonal continental climate with hot summers and cold winters. Yet the paleoclimatic evidence is conflicting. There are several indicators of an arid climate, including the following: red sandstones and shales that contain few fossils, lithified dune deposits with cross-bedding, salt pseudomorphs in marls, mudcracks, and evaporites. On the other hand, there is evidence for strong seasonal precipitation, including braided fluvial (riverine) sediments, clay-rich deltaic deposits, and red beds of alluvial and fluvial origin. This dilemma is best resolved by postulating a monsoonal climate, particularly during the Middle and Late Triassic, over wide areas of Pangea. Under these conditions, cross-equatorial monsoonal winds would have brought strong seasonal precipitation to some areas, especially where these winds crossed large expanses of open water.”
—You are in the Early Triassic, Hothouse Earth 250 million years ago, a few million years after the worst mass extinction in history.
#Winguth, A. et al. (2015): Transition into a Hothouse World at the Permian–Triassic boundary—A model study. Palaeogeography, Palaeoclimatology, Palaeoecology
Vol. 440
https://www.sciencedirect.com/science/article/abs/pii/S0031018215004927
Quote: “The climatic transition from the Late Permian to the Early Triassic is of great significance because it encompasses a transition into a hothouse world (Joachimski et al., 2012; Sun et al., 2012), widespread variation in anoxia (Wignall and Hallam, 1992, 1993; Knoll et al., 1996; Hallam and Wignall, 1997; Isozaki, 1997; Ward et al., 2001; Wignall and Twitchett, 2002; Wignall and Newton, 2003; Kump et al., 2005; Meyer et al., 2008; Cao et al., 2009; Shen et al., 2010; Wignall et al., 2010), and ocean acidification (Fraiser and Bottjer, 2007a,b; Heydari et al., 2008; Payne et al., 2010; Clapham and Payne, 2011; Black et al., 2014; Clarkson et al., 2015). The mass extinction at the Permian–Triassic boundary (PTB) 252.3 Ma (Shen et al., 2011), affected over 90% of marine species (Raup and Sepkoski, 1982; Erwin, 1994; Sepkoski, 1995; Kozur, 1998; Bambach et al., 2004; Visscher et al., 2004; Clapham and Bottjer, 2007; Knoll et al., 2007; Alroy et al., 2008) and was a major driver of macroevolutionary change in the early Mesozoic (Burgess et al., 2014). Common hypotheses for causes of the event include the massive volcanic eruption of the Siberian Traps (Renne and Basu, 1991; Campbell et al., 1992; Renne et al., 1995; Yin and Nie, 1996; Bowring et al., 1998; Kamo et al., 2003; Mundil et al., 2004; Wignall, 2007; Ganino and Arndt, 2009; Svensen et al., 2009; Sobolev et al., 2011) and associated volatile releases (Black et al., 2012), a massive bolide impact (Becker et al., 2001; Basu et al., 2003), thermogenic methane emission from intrusions into the West Siberian Coal Basin (Payne and Kump, 2007; Retallack and Jahren, 2008; Svensen et al., 2009) as supported by coal fly ash deposits in lake deposits (Grasby et al., 2011) and marine organisms (Nestell et al., 2015), and extensive wild fires (Hudspith et al., 2014). Whether there was gradual, one-step or multi-stepped carbon release to the atmosphere is still under debate (Payne and Clapham, 2012).
#Twitchett, R. J. (2007): Climate change across the Permian/Triassic boundary. In: Deep-Time Perspectives on Climate Change: Marrying the Signal from Computer Models and Biological Proxies (Editor(s) M. Williams; A. M. Haywood; F. J. Gregory; D. N. Schmidt). The Micropalaeontological Society, Special Publications
https://pubs.geoscienceworld.org/gsl/books/edited-volume/1939/chapter-abstract/107589704/Climate-change-across-the-Permian-Triassic?redirectedFrom=PDF
Quote: “Studies of high latitude palaeosols and data from isotope analyses of biogenic and abiogenic marine carbonates suggest that the Permian–Triassic was a time of global warming, although some of the isotope data are derived from samples that have clearly been altered during diagenesis. Many authors have attributed Permian–Triassic temperature rise to a runaway greenhouse driven by elevated atmospheric CO2 levels, causing temperature rise and breakdown of methane hydrates, which in turn led to methane release and oxidation, thus further increasing atmospheric CO2.”
#Judd, J. E. et al. (2024): A 485-million-year history of Earth’s surface temperature. Science, Vol. 385 (6715) https://www.science.org/doi/10.1126/science.adk3705
—The planet is still suffering from a permanent fever. Volcanism and the runaway greenhouse effect has transformed the planet into hell. There is three to five times more CO2 in the air than in the human era.
We are currently at over 400 ppm (part per million), while the level reached 1500 around 250 million years ago (Fig. 1, pCO2 (ppmV)).
#Lan, X., Tans, P. & K.W. Thoning (2024): Trends in globally-averaged CO2 determined from NOAA Global Monitoring Laboratory measurements. Version Thursday, 05-Dec-2024
#Joachimski, M. M. (2022): Five million years of high atmospheric CO2 in the aftermath of the Permian-Triassic mass extinction. Geology, Vol. 50 (6)
—The massive supercontinent Pangea creates the largest desert in history that never sees any rain.
#Benton, M. J. (2018): Hyperthermal-driven mass extinctions: killing models during the Permian–Triassic mass extinction. Philosophical transactions. Series A, Mathematical, physical, and engineering sciences Vol. 376 (2130)
https://royalsocietypublishing.org/doi/pdf/10.1098/rsta.2017.0076
Quote: “Permian–Triassic climates were generally warm. The supercontinent Pangaea extended from pole to pole, and a deep oceanic gulf, Tethys, split the supercontinent around the Equator (figure 3). Climate modelling [48,49] of this unusual continental and oceanic configuration highlights the broad tropical belt with a strong monsoonal regime. Extreme continental conditions prevailed, with hot summers and cold winters. The poles were ice-free, and polar sediments include coals, plants and spoils typical of cool temperate latitudes. In the Late Permian, Pangaea was characterized by high average temperatures, and a very broad semiarid belt around the more humid Equator [50]. In many regions, aridity increased across the PTB and into the Early Triassic [16], with the northward and southward expansion of low-latitude arid belts into the vast formerly humid basins of European Russia and South Africa (figure 3). Primary sedimentological evidence of aeolian sediments, such as the preservation of ancient dunes, suggests an expansion through the PTB. Extensive areas of aeolian dune sandstones are reported from the Late Permian of the Paraná Basin of eastern South America, and then at the PTB from new locations, including the rift basins of Iberia, the south Urals and central Europe, in areas that had formerly been humid during the Late Permian [16]. This expansion of the arid belt was countered by increases in precipitation in other regions to balance the hydrological cycle.”
#Abrantes Jr., F. R. et al. (2019): Register of increasing continentalization and palaeoenvironmental changes in the west-central pangaea during the Permian-Triassic, Parnaíba Basin, Northern Brazil. Journal of South American Earth Sciences
Vol. 93
https://www.sciencedirect.com/science/article/abs/pii/S0895981118304127?via%3Dihub
Quote: “The Permian-Triassic interval (298 to 201 million of years) was marked by one of the largest collages of Earth continental blocks, forming through collisional events, the assembly of Pangaea supercontinent (Van der Voo et al., 1984; Crowley et al., 1989; Van der Voo, 1993; Scotese & Langford, 1995; Scotese et al., 1999).
(...)
Pangea continentalization and climatic changes propitiated the development of extensive arid areas and red beds in the tropical zones which attest highly oxidizing environments in acid-saline lake systems surrounded by aeolian-dominated areas (Parrish et al., 1986; Benison et al., 1998; Scotese et al., 1999; Benison & Goldstein, 2001; Zharkov & Chumakov, 2001; Andeskie et al., 2018). During the Permian-Triassic period, these continental saline environments extended regionally in the north of equatorial Pangaea, compound a stark red landscape of acidic lakes in an arid climate (Andeskie et al., 2018).”
#Preto, N. et al. (2010): Triassic climates — State of the art and perspectives. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 290
https://www.sciencedirect.com/science/article/abs/pii/S0031018210001434?via%3Dihub
Quote: “The palaeogeography of the Triassic is distinctive. All continents were merged into a single supercontinent, Pangaea, centred more or less on the equator, with exposed land extending from about 85°N to 90°S (Ziegler et al., 1983). The continent was surrounded by the Panthalassa Ocean, and a deep oceanic gulf, Tethys, cutting into the supercontinent (Fig. 1). This ocean was latitudinally confined to the tropical–subtropical belt between 30° North and 30° South (Ziegler et al., 2003). The concentration of exposed land at low and mid-latitudes, and the presence of a warm sea-way would have maximized summer heating in the circum-Tethyan part of the continent (e.g. Kutzbach and Gallimore, 1989; Dubiel et al., 1991). Furthermore, extreme continentality with hot summers and relatively cold winters, and a strong monsoonal circulation are expected (e.g. Robinson, 1973; Kutzbach and Gallimore, 1989). The climatic consequences of such a “mega-monsoon” are, according to Parrish (1993): 1) abundant, but extremely seasonal rainfall, concentrated during the summer in the northern hemisphere; 2) a relatively dry equatorial region in the eastern part of Pangaea, facing the western Tethys; and 3) breakdown of the zonal climate pattern.
#Kidder, D. L. & Worsley, T. R. (2004): Causes and consequences of extreme Permo-Triassic warming to globally equable climate and relation to the Permo-Triassic extinction and recovery. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 203 (3-4)
https://www.sciencedirect.com/science/article/abs/pii/S0031018203006679
—The gigantic ocean is warm even deep below.
There are a couple of indications for warm ocean, even in deep layers. For example, instead of cold water sinking at the poles, warm, salty water from mid-latitude evaporation sank to the ocean depths, maintaining high temperatures even at depth.
#Kidder, D. L. & Worsley, T. R. (2004): Causes and consequences of extreme Permo-Triassic warming to globally equable climate and relation to the Permo-Triassic extinction and recovery. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 203 (3-4)
https://www.sciencedirect.com/science/article/abs/pii/S0031018203006679
Quote: “As the Earth warmed, dry climates expanded to mid-latitudes, causing latitudinal expansion of the Ferrel circulation cell at the expense of the polar cell. Increased coastal evaporation generated O2- and nutrient-deficient warm saline bottom water (WSBW) and delivered it to a weakly circulating deep ocean. Warm, deep currents delivered ever more heat to high latitudes until polar sinking of cold water was replaced by upwelling WSBW. With the loss of polar sinking, the ocean was rapidly filled with WSBW that became increasingly anoxic and finally euxinic by the end of the Permian.
Fossil oxygen isotope values (δ18O) from conodonts and brachiopods indicate that the ocean was not only unusually warm at the surface but also at depth. Oxygen occurs in two stable isotopes: the heavier 18O and the lighter 16O. In warm water, organisms incorporate more of the lighter 16O into their skeletal material, resulting in lower δ18O values. Typically, brachiopods, which lived on the seafloor, would have higher δ18O values than free-swimming conodonts, since deep water is usually colder. However, both fossil groups show low δ18O values, meaning that deep waters were also warm.
#Grossman, E. L. & Joachimski, M. M. (2022): Scientific Reports Vol. 12 (8938)
Ocean temperatures through the Phanerozoic reassessed
https://www.nature.com/articles/s41598-022-11493-1.pdf
Quote: “The 18O/16O ratios of biogenic carbonate and apatite are an essential proxy for paleotemperature and seawater δ18O.
(...)
Te δ18O values decrease sharply from~20.4 to~17.7‰ across the Permian–Triassic boundary with low δ18O values persisting in the Early Triassic.
—Two superheated currents circulate around the globe, pumping extreme amounts of heat and moisture into the atmosphere. There is no ice even at the poles.
#Kidder, D. L. & Worsley, T. R. (2004): Causes and consequences of extreme Permo-Triassic warming to globally equable climate and relation to the Permo-Triassic extinction and recovery. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 203 (3-4)
https://www.sciencedirect.com/science/article/abs/pii/S0031018203006679
#Woods, A. D. (2005): Paleoceanographic and paleoclimatic context of Early Triassic time. Comptes Rendus Palevol, Vol. 4 (6–7)
https://www.sciencedirect.com/science/article/pii/S1631068305000825
—You are stuck in the center of the desert, isolated by the vast and endless ancient land masses. One of the most hostile environments Earth has ever produced.
During the Late Permian and Triassic, the formation of the supercontinent Pangea created vast arid regions due to limited oceanic moisture, reinforced by monsoonal precipitation patterns and perhaps rain-shadow effects from the Variscan mountains. While episodic wetter phases led to temporary fluvial activity and playa lakes, the overall dry conditions favored the formation of extensive evaporite deposits, with aridity gradually decreasing as Pangea drifted northward in the Late Triassic.
#Mckie, T. (2017): Paleogeographic Evolution of Latest Permian and Triassic Salt Basins in Northwest Europe. In: Permo-Triassic Salt Provinces of Europe, North Africa and the Atlantic Margins, Chapter: 7
Quote: “The assembly of the supercontinent of Pangea created vast areas of terrestrial dryland. In the Late Permian and Triassic, intracratonic rifts propagated into this arid continental interior and were infilled by sediment supplied by seasonal monsoon flooding.
(...)
The extensive tracts of continental landscape and paucity of open water bodies resulted in widespread Pangean aridity. Greenhouse conditions prevailed, with the polar regions largely ice-free. Precipitation was dominated by monsoons originating from Panthalassa and Tethys (Kutzbach & Gallimore, 1989; Parrish, 1993; Sellwood & Valdes, 2007), while the interior remained arid to semiarid (Fig. 3). The Variscan uplands may have created a rain shadow (Kendall et al., 2003), restricting precipitation and runoff into the interior. Late Permian conditions in NW Europe were characterized by both arid basins and catchments. However, in the Early to Middle Triassic the basins were supplied by fluvial systems sourced from wetter catchments during highly erratic pluvial episodes (Fig. 3). These may have been triggered by volcanism in the Tethys region and more distant large igneous provinces (Feist-Burkhardt et al., 2008; McKie, 2014; Trotter, Williams, Nicora, Mazza, & Rigo, 2015). Runoff from the Variscides decreased markedly by the Late Anisian (van der Zwan & Spaak, 1992), but persisted in the north throughout the Triassic (McKie & Williams, 2009). The erratic climate subsequently stabilized through the Norian (Fig. 3), with the northward drift of Pangea ultimately bringing the NW European region under semiarid, vegetated conditions with year-round soil moisture that precluded the formation of evaporite bodies.”
#Preto, N. et al. (2010): Triassic climates — State of the art and perspectives. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 290
https://www.sciencedirect.com/science/article/abs/pii/S0031018210001434?via%3Dihub
Quote: “The palaeogeography of the Triassic is distinctive. All continents were merged into a single supercontinent, Pangaea, centred more or less on the equator, with exposed land extending from about 85°N to 90°S (Ziegler et al., 1983). The continent was surrounded by the Panthalassa Ocean, and a deep oceanic gulf, Tethys, cutting into the supercontinent (Fig. 1). This ocean was latitudinally confined to the tropical–subtropical belt between 30° North and 30° South (Ziegler et al., 2003). The concentration of exposed land at low and mid-latitudes, and the presence of a warm sea-way would have maximized summer heating in the circum-Tethyan part of the continent (e.g. Kutzbach and Gallimore, 1989; Dubiel et al., 1991). Furthermore, extreme continentality with hot summers and relatively cold winters, and a strong monsoonal circulation are expected (e.g. Robinson, 1973; Kutzbach and Gallimore, 1989). The climatic consequences of such a “mega-monsoon” are, according to Parrish (1993): 1) abundant, but extremely seasonal rainfall, concentrated during the summer in the northern hemisphere; 2) a relatively dry equatorial region in the eastern part of Pangaea, facing the western Tethys; and 3) breakdown of the zonal climate pattern.
—You shoot over some of the mightiest mountains Earth has ever seen and stop at the shores of the Tethys Sea.
Pangaea was traversed by the Central Pangean Mountains, a huge mountain range up to 5,000m that was formed about 300 million years ago by the collision of continents to form the supercontinent Pangaea. It stretched from North America across Europe to Asia and was formed by various orogenies (mountain formations). Today, only eroded remnants remain, including the Appalachian Mountains in North America, the Variscan Mountains in Europe and the Atlas Mountains in North Africa.
#Scotese, C. (2001): Atlas of Earth History, Paleomap Project
#Pfeifer, L. S. et al. (2020): Loess in eastern equatorial Pangea archives a dusty atmosphere and possible upland glaciation. GSA Bulletin, Vol. 133 (1-2)
Quote: “Global paleogeography in the late Paleozoic was governed by the assembly of Pangea, and formation of the low-latitude Central Pangean Mountains, which spanned from the Variscan-Hercynian system of Europe (Ziegler et al., 1979; Ziegler, 1996) west to the Appalachian-Ouachita-Marathon uplifts of North America.
(...)
Hypothesized upland glaciation in the Variscan paleomountains of eastern equatorial Pangea was originally posited by Julien (1895), followed by several others (Grangeon, 1960; Dewolf, 1988; Sabrier et al., 1993; Becq-Giraudon and Van Den Driessche, 1994; Becq-Giraudon et al., 1996), but it remains controversial and not generally accepted. Paleoaltitude estimates for the Variscan Mountains range widely (<1000 to >5000 m; e.g., Becq-Giraudon and Van Den Driessche, 1994; Becq-Giraudon et al., 1996; Keller and Hatcher, 1999; Fluteau et al., 2001; Schneider et al., 2006; Roscher and Schneider, 2006).”
—A few Lystrosaurus feeding on them eye you curiously.
There is a debate about the conditions in which Lystrosaurus lived. One side argues that it lived semi-aquatically, while the others see the animal as living in purely terrestrial environments where it changed the landscape through digging or even aquatic environments.
#Canoville, A. & Laurin, M. (2010): Evolution of humeral microanatomy and lifestyle in amniotes, and some comments on palaeobiological inferences. Biological Journal of The Linnean Society, Vol. 100 (2)
https://academic.oup.com/biolinnean/article-abstract/100/2/384/2450634?redirectedFrom=fulltext
Quote: “The therapsid Lystrosaurus (Fig. 2E) was abundant in the Late Permian and the Early Triassic. Some studies have considered it as terrestrial and perhaps fossorial on the basis of skeletal features such as a broad scapula or short and robust distal bones of the forelimbs (King, 1991; King & Cluver, 1991; Retallack, Smith & Ward, 2003). Other studies hold an amphibous or mostly aquatic lifestyle more probable on the basis of morphological (e.g. nostrils at the top of the skull; Broom, 1903; Cluver, 1971; Ray, 2006) and microanatomical (Germain & Laurin, 2005; Ray, Chinsamy & Bandyopadhyay, 2005) characters, and on its abundance in the fossil record.
(...)
The lifestyle of the Permo-Triassic therapsid Lystrosaurus has long been debated. It was said to be aquatic, terrestrial or burrowing (King, 1991; King & Cluver, 1991; Ray et al., 2005). Specimens of Lystrosaurus have been reported from South Africa, India, Antarctica, China, Russia, and possibly Australia (King & Jenkins, 1997). In the South African PermoTriassic Karoo Basin, this taxon was so abundant that it is used as a stratigraphic marker. LD1 yields an aquatic habitat for Lystrosaurus (Fig. 6) because of the broad transition zone (high S-value) and porous cortex (low Cp; Fig. 2E). For character optimization, to be coherent with previous interpretations and because of its morphology, we consider this genus amphibious. Microanatomy of the radius (Germain & Laurin, 2005) and of several other bones (Ray et al., 2005) also suggests an amphibious lifestyle. Such a lifestyle would explain the great number of its fossils by taphonomic processes: throughout geological history, the fossil record has always shown a bias toward aquatic animals. Moreover, Battail (1997) noted that Lystrosaurus georgi Kalandadze, 1975 was found in association with ostracods and branchiopods.”
#Ray, S. et al. (2003): Lystrosaurus murrayi (therapsida, dicynodontia): Bone histology, growth and lifestyle adaptations. Palaeontology, Vol. 48
https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1475-4983.2005.00513.x
Quote: “Early studies by Watson (1912, 1913), Broom (1932) and Cluver (1971) suggested that Lystrosaurus was essentially an aquatic animal that inhabited a swampy environment. However, King (1991) concluded that the skeletal characteristics of Lystrosaurus such as the flaring ⁄wide scapular blade, lateromedially extended and flattened antebrachium, and short and robust manus are also present in digging animals, and did not support the hypothesis that it was aquatic. The down-turned snout, large premaxilla and short temporal area of Lystrosaurus resulted in a powerful bite, which was necessary for chopping and shredding plant matter (King and Cluver 1991). Recently, small articulated skeletons of Lystrosaurus were found in burrow casts assigned to the ichnogenus Histioderma (Groenwald 1991; Retallack et al. 2003). However, Retallack et al. (2003) suggested that Lystrosaurus species were amphibious⁄semi-aquatic in nature, waded into water for food and probably lived in a wide range of habitats as they occur in almost all types of Triassic palaeosols⁄ pedotypes including those that supported submerged vegetation. Hence, the peculiar cranial features and varied interpretations of lifestyle (Watson 1912; Cluver 1971; King 1991; King and Cluver 1991; Retallack et al. 2003) make Lystrosaurus an enigmatic dicynodont.”
—The water is murky and looks sickly and milky. Colourful mats of bacteria float on the surface like oil slicks.
There are evidences that the massive decline of metazoans (multicellular animals) due to the Perm-Triassic mass extinction significantly reduced competition, allowing microbial mats to proliferate in shallow, sunlit marine environments. Additionally, high temperatures, altered chemical conditions (carbonate oversaturation), and possibly increased nutrient availability facilitated the expansion of these microbes, leading to their widespread dominance in coastal regions of the Early Triassic.
#Feng, X. et al. (2019): Unusual shallow marine matground-adapted benthic biofacies from the Lower Triassic of the northern Paleotethys: Implications for biotic recovery following the end-Permian mass extinction. Earth-Science Reviews
Vol. 189
https://www.sciencedirect.com/science/article/abs/pii/S001282521830206X?via%3Dihub
Quote: “In addition to unusual ichnofaunal and faunal behaviors, microbial blooms also characterize the marine ecosystems during the earliest Triassic. The sedimentary record is characterized by widespread microbialites and microbially induced sedimentary structures (MISSs), related to microbial mats in carbonate and siliciclastic successions, respectively (Mata and Bottjer, 2009a). Microbial proliferation during the Early Triassic, or in the aftermath of other biotic crises, is regarded as a response to periods of lower benthic biodiversity and reduced bioturbation (Pflüger, 1999; Pruss et al., 2004, 2006; Mata and Bottjer, 2009a; Algeo
et al., 2011; Chen and Benton, 2012; Buatois et al., 2013; Rakociński and Racki, 2016; Chu et al., 2017).”
#Foster, W. J. et al (2019): Suppressed competitive exclusion enabled the proliferation of Permian/Triassic boundary microbialites. The Depositional Record, Vol. 6 (1)
https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/dep2.97
Quote: “During the earliest Triassic microbial mats flourished in the photic zones of marginal seas, generating widespread microbialites. It has been suggested that anoxic conditions in shallow marine environments, linked to the end-Permian mass extinction, limited mat-inhibiting metazoans allowing for this microbialite expansion.
(...)
Other environmental stressors that would have suppressed mat-inhibiting metazoans in shallow marine environments include periods of high salinity (Heindel et al., 2018), eutrophication (Meyer et al., 2011; Schobben et al., 2015) and high temperatures (Sun et al., 2012; Schobben et al., 2014).”
—This hot ocean can’t hold much oxygen, especially in deeper layers. Bivalves and bacteria are the only species that thrive here.
Our consulting expert pointed out that the claim may not apply universally across all marine environments, as around 5% of marine species from all phyla survived the Permian-Triassic extinction event and that there were refuges where biodiversity remained relatively high.
#Winguth, A. (2016): Research Focus: Changes in productivity and oxygenation during the Permian-Triassic transition. Geology, Vol. 44 (9)
Quote: “Potential causes for the marine extinction are controversial and include a lethal hothouse climate with tropical ocean water temperatures in the Tethys Ocean exceeding 40 °C (Sun et al., 2012). Increased ocean stratification and lower oxygen solubility induced by global warming could have contributed to a widespread decline in marine dissolved oxygen concentration, resulting in widespread shallow marine euxinic conditions, expansion of the oxygen minimum zone, and global deep-sea anoxia (e.g., Isozaki, 1997; Knoll et al., 1996).”
#Huang, Y. et al. (2018): A Griesbachian (Early Triassic) Mollusc Fauna from the Sidazhai Section, Southwest China, with Paleoecological Insights on the Proliferation of Genus Claraia (Bivalvia). Journal of Earth Science, Vol. 29 (4)
https://link.springer.com/article/10.1007/s12583-017-0966-7
Quote: “We reported a new Griesbachian (Early Triassic) mollusc fauna, dominated and characterized by Claraia fossils, from deep water settings in South China. The butterfly-shaped preserved Claraia fossils could indicate an ideal in situ preserved fauna, which linked both the lifestyle and living environments of Claraia. Claraia had an epibyssate mode of life, and usually lay on soft substrates with its right valve. Meanwhile, the shallow- and deep-marine environments became dysoxic to anoxic globally during the early Early Triassic, supported by evidence from the geochemical and pyrite framboids. Thus, genus Claraia could have lived in dysoxic/anoxic waters, and its flourishing was likely due to its physiological characteristics. Claraia might have hosted chemosymbionts and thus survived in dysoxic to anoxic waters. The global distribution of Claraia was probably related to its planktonic larval stage. Additionally, Claraia is characteristic of a significant disaster taxon during the Early Triassic in South China.”
—Each wave that hits the shore releases a mist that makes your eyes and throat burn, carrying the rotten-egg stench of hydrogen sulfide up from the oxygen-starved depths.
#Grice, K. et al. (2005): Photic Zone Euxinia During the Permian-Triassic Superanoxic Event. Science, Vol. 307
https://www.science.org/doi/10.1126/science.1104323
Quote: “The most severe extinction of the past 500 million years occurred in the Late Permian (1, 2). The biotic crisis was accompanied by an oceanic anoxic event (OAE) that may have lasted up to 8 million years. Although different authors report various anoxic intervals, the most severe conditions persisted during the first 1 to 3 million years (3, 4). Anoxia has been proposed to have had a major role in driving the extinction (5, 6); surface outcropping of sulfidic waters and emissions of hydrogen sulfide to the atmosphere provide a kill mechanism that might account for the terrestrial and marine extinctions (7).”
#Zhou, W. et al. (2017): Expansion of photic-zone euxinia during the Permian–Triassic biotic crisis and its causes: Microbial biomarker records. Palaeogeography, Palaeoclimatology, Palaeoecology.
Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 474
https://www.sciencedirect.com/science/article/abs/pii/S003101821630219X?via%3Dihub
Quote: “Marine euxinia is likely to have been a major player in the endPermian mass extinction. Generation of a long-term reservoir of euxinic waters at intermediate ocean depths would have created the potential for episodic shallowing of the chemocline or eruptions of sulfidic waters into the ocean-surface layer. A major event of this type may have caused a rapid kill-off of shallow-marine benthos during the end-Permian mass extinction, and episodic expansion of PZE following the EPME may have been a factor delaying the recovery of Early Triassic marine ecosystems.”
—You are near the equator, in the late Carboniferous, 320 million years ago. The atmosphere is thick with moisture. The climate is locked in a never ending wet super summer without any other seasons.
Around 320 million years ago, the equatorial climate was consistently warm and humid, supporting ever-wet conditions with vast coal swamps dominated by spore-producing plants. Although Gondwanan glaciation influenced global climate, the equator remained stable, but increasing aridity towards the Permian led to a shift from wetland vegetation to more drought-resistant seed plants.
#DiMichele, W. A. et al. (2001): Response of Late Carboniferous and Early Permian Plant Communities to Climate Change. Annual Review of Earth and Planetary Sciences. Vol. 129
https://www.annualreviews.org/content/journals/10.1146/annurev.earth.29.1.461
Quote: “Global climate changes, largely drying, forced vegetational changes, resulting in a change to a seed plant–dominated world, beginning first at high latitudes during the Carboniferous, reaching the tropics near the Permo-Carboniferous boundary.
(...)
When the Carboniferous or “Coal Age” is popularly envisioned, steaming tropical jungles, giant insects, and bizarre plants take center stage. Although coal swamps were prominent in tropical lowland-wetland areas, distinct vegetation occupied tropical extrabasinal areas and the northern and southern temperate zones (DiMichele & Aronson 1992, Chaloner & Lacey 1973, Chaloner & Meyen 1973, Meyen 1982, Cúneo 1996). The Late Carboniferous was a cold interval in geological history. The expansion and contraction of glaciers, primarily in the Southern Hemisphere (Martini 1997), affected global climate and vegetational patterns in ways similar to those of the Pleistocene.
(...)
The tropical Euramerican Province consisted of at least two major biomes: that of wetlands and that of seasonally dry environments (Cridland & Morris 1963; Havlena 1971, 1975; Broutin et al 1990; DiMichele & Aronson 1992; Falcon-Lang & Scott 2000).”
#Sahney, S. et al. (2010): Rainforest collapse triggered Carboniferous tetrapod diversification in Euramerica. Geology, Vol. 38 (12)
https://www.researchgate.net/publication/257409574_Rainforest_collapse_triggered_Carboniferous_tetrapod_diversification_in_Euramerica
Quote: “During the latter part of the Carboniferous (318–299 Ma), Europe and North America (Euramerica) were positioned over the equator, and were covered, at times, by humid tropical rainforest (DiMichele et al., 2007). This biome, colloquially referred to as the Coal Forests, comprised a heterogeneous vegetation mosaic (Gastaldo et al., 2004) inhabited by a rich terrestrial fauna (Falcon-Lang et al., 2006). As climate aridifi ed through the later Paleozoic, these rainforests collapsed, eventually being replaced by seasonally dry Permian biomes (Montañez et al., 2007).”
—Colliding continents are covered by the largest swamps the planet will ever see. A paradise for plants, growing faster than their dead biomass can decompose. What will be an endless desert in 70 million years is now an endless alien jungle.
During the Late Carboniferous, vast swamp forests of Lycophytes, ferns, and seed plants stored large amounts of carbon, which accumulated in oxygen-poor wetlands and eventually formed coal. The waterlogged, anoxic conditions inhibited decomposition, allowing organic material, especially the bark of tree Lycophytes, to be preserved. Additionally, lignin-decomposing fungi had not yet evolved, further slowing decay and enabling the massive coal deposits of this period.
#Hibbet, D. et al. (2016): Climate, decay, and the death of the coal forests. Current Biology, Vol. 26 (13)
https://www.sciencedirect.com/science/article/pii/S0960982216000646
Quote: “An unparalleled interval of carbon sequestration in Earth’s history occurred during the Late Carboniferous (Pennsylvanian) and Permian Periods (ca. 323–252 Ma), when arborescent vascular plants related to living club mosses (Lycophytes), ferns (Monilophytes), horsetails (Equisetophytes) and seed plants (Spermatophytes) formed extensive forests in coastal wetlands. On their death, these plants became buried in sediments, where they transformed into peat, lignite, and, finally, coal. The botanical origin of coal is not disputed, but the causal factors that determined the rate of Corg sequestration and that limited the extent of coal forests are matters of debate. One theory is that abiotic factors were solely responsible for shifts in rates of Corg burial. Under this view, the high rate of carbon sequestration during the PermoCarboniferous was caused by unusually widespread mire environments with anoxic, waterlogged conditions, which inhibited decay, and contractions in coal forests were caused by climatic shifts toward drier conditions. An alternative hypothesis, proposed by Robinson, introduced, in addition to geological and environmental factors, the concept that biological interactions among organisms might also be important in coal formation. Specifi cally, the dramatic accumulation of Corg in the Permo-Carboniferous occurred in part because the fungi that are able to effi ciently decompose lignin (a recalcitrant, heterogeneous plant polymer) had yet to evolve and diversify. Robinson also suggested that coal-age spore-bearing plants had an unusually high lignin content compared with the seed plants that would eventually replace them as dominant forest trees.”
#Nelsen, M. P. et al. (2016): Delayed fungal evolution did not cause the Paleozoic peak in coal production. PNAS, Vol 133 (9)
https://www.pnas.org/doi/pdf/10.1073/pnas.1517943113
Quote: “The Carboniferous−Permian marks the greatest coal-forming interval in Earth’s history, contributing to glaciation and uniquely high oxygen concentrations at the time and fueling the modern Industrial Revolution. This peak in coal deposition is frequently attributed to an evolutionary lag between plant synthesis of the recalcitrant biopolymer lignin and fungal capacities for lignin degradation, resulting in massive accumulation of plant debris. Here, we demonstrate that lignin was of secondary importance in many floras and that shifts in lignin abundance had no obvious impact on coal formation. Evidence for lignin degradation— including fungal—was ubiquitous, and absence of lignin decay would have profoundly disrupted the carbon cycle. Instead, coal accumulation patterns implicate a unique combination of climate and tectonics during Pangea formation.
(...)
During the Carboniferous, a massive amount of organic debris accumulated in warm, humid−perhumid equatorial wetlands formed during glacial periods, which was subsequently buried during interglacial phases (47).
(...)
The magnitude of Carboniferous−Permian coal production was not a product of increased plant lignin content coupled with the delayed evolution of lignin-degrading fungi but rather a unique confluence of climate and tectonics.”
#Torsvik, T. H. & Cocks R. (2016): 9 - Carboniferous. Earth History and Palaeogeography. Cambridge University Press
https://www.cambridge.org/core/books/abs/earth-history-and-palaeogeography/carboniferous/8CF5A3BF3F677A971C7E71887B890BBB
—A huge variety of life is thriving in this period.
The Carboniferous was a period of significant marine and terrestrial biodiversity increase. Despite previous assumptions of a mass extinction and sluggish evolution during the Late Paleozoic Ice Age (LPIA), new data reveal a substantial rise in marine species and genus richness. The Carboniferous-Permian Biodiversification Event (CPBE) led to a rapid increase in marine taxa from the late Visean to the early Permian (~333 to ~298 million years ago).
#Shi, Y. et al. (2021): Carboniferous-earliest Permian marine biodiversification event (CPBE) during the Late Paleozoic Ice Age. Earth-Science Reviews. Vol. 220
https://www.sciencedirect.com/science/article/abs/pii/S0012825221002002?via%3Dihub
Quote: “The Late Paleozoic Ice Age (LPIA) is a critical interval for marine ecosystems when marine fauna was viewed to have experienced a second-order mass extinction and a “sluggish” evolution with low origination and extinction rates. However, our recent study discovered that this ice age was accompanied by a rapid, significant increase of marine fauna species and genus richness.
(...)
Recently a high-resolution Paleozoic marine biodiversity pattern has been recovered, from which a distinct Carboniferous-Permian Bio diversification Event (CPBE) was recognized and presented that both species and genus richness of marine fauna quickly increased in the late Visean of the Carboniferous to the earliest Permian, also the LPIA duration (Fig. 1; Fan et al., 2020).
#Dunne, E. M. et al. (2018): Diversity change during the rise of tetrapods and the impact of the ‘Carboniferous rainforest collapse’. Proceedings of the Royal Society B, Vol 285 (1872)
https://royalsocietypublishing.org/doi/10.1098/rspb.2017.2730
Quote: “Tetrapods (four-limbed vertebrates) first appeared on land in the late Devonian [1,2], and during the Carboniferous and early Permian established the first terrestrial vertebrate communities. In the early Carboniferous, these amphibian-like early tetrapods radiated rapidly and diversified into a wide variety of morphologies and sizes [3]. Later in the Carboniferous, crown amniotes appeared [4], and by the early Permian, the terrestrial vertebrate fauna was dominated by synapsids (the mammalian stem-group), such as edaphosaurids and sphenacodontids, alongside a diverse array of basal reptiles (e.g. captorhinids) and amphibians [5,6].
This diversification occurred as the surrounding environment was transitioning from wetlands in the Carboniferous to more arid conditions in the Permian. During the late Carboniferous, Euramerica (Europe and North America) lay at the equator and was predominantly covered by tropical rainforests, commonly referred to as the ‘Coal Forests’ [7]. During the Kasimovian (approx. 303–307 Ma), these rainforests began to disappear from large parts of the globe, and by the early Permian had been replaced in many regions by dryland vegetation as a more arid climate developed [8,9]. This ‘rainforest collapse’ culminated in what is considered one of two mass extinction events evident in the plant fossil record [10].”
—The thick humid air smells of sweet decay but breathing makes you dizzy - your vision seems too sharp, your thoughts slightly frantic. The dense plant cover has supercharged the atmosphere with oxygen, 60% higher than in the human era, and your body is trying to cope.
#Kutschera, U. & Niklas, K. (2013): Metabolic scaling theory in plant biology and the three oxygen paradoxa of aerobic life. Theory in biosciences, Vol. 132 (4)
#Berner, A. et al. (2003): Phanerozoic Atmospheric Oxygen. Annual Review of Earth and Planetary Sciences, Vol. 31
https://www.annualreviews.org/content/journals/10.1146/annurev.earth.31.100901.141329
—Which is great for the dominant land animals which have conquered every niche of this majestic garden: bugs. You are stuck in the golden age of arthropods. In this oxygen-rich world, they have evolved to sizes that will never be possible again. They are innumerable and everywhere.
The following paper argues that the hyperoxic atmosphere of the Carboniferous and Permian periods played a key role in the evolution of giant insects by enabling larger body sizes through more efficient tracheal systems. However, it also discusses alternative hypotheses, including the occupation of open ecological niches, favorable environmental conditions, predation pressure, biomechanical constraints of the exoskeleton, and competition from vertebrates.
#Harrison, J. F. et al. (2010): Atmospheric oxygen level and the evolution of insect body size. Proceedings of the Royal Society B, Vol. 277(1690)
https://royalsocietypublishing.org/doi/full/10.1098/rspb.2010.0001#d1e1293
Quote: “More than 300 Ma, giant insects up to 10-fold larger than those in similar groups alive today roamed the earth (Shear & Kukalova-Peck 1990; Grimaldi & Engel 2005). It has been proposed that atmospheric hyperoxia (defined here as atmospheric oxygen partial pressures (aPO2) greater than the current 21 kPa) in the Palaeozoic was the major factor allowing the evolution of giant insects and other animals, with subsequent hypoxia (defined here as aPO2 below present day) being responsible for their disappearance (Graham et al. 1995; Dudley 1998; Berner 2006b; Ward 2006). While a number of evolutionary events have been tied to changes in atmospheric oxygen level (Berner et al. 2007), the hypothesis that variation of aPO2 is responsible for historical changes in the body size of insects has recently been challenged owing to uncertainties in physiological mechanisms and in patterns of oxygen and body size variation through time (Butterfield 2009).
(...)
One possible explanation for Palaeozoic insect gigantism is niche displacement. Since the body sizes of animals respond to predation and competition (Blackburn & Gaston 1994), it is plausible that giant insects evolved into open niches, but that these species were later displaced by vertebrates filling the same ecological roles. Evolution of these giants has also been hypothesized to have occurred as a response to stable, optimal environmental conditions, and the availability of coal-swamp forests as a new habitat with little competition or predation (Briggs 1985). Such improved environmental conditions could directly increase insect abundances and/or shift body size distributions. The large size of some of the Palaeozoic insects could have been the result of size-selection by predators, or the need for greater force generation in ground litter filled with tree branches (Shear & Kukalova-Peck 1990).”
—Here in the clearing you can see the sky above the canopy glow shrieking red, intensifying at an alarming pace. The extreme humidity here creates sudden, violent thunderstorms. And the oxygen-rich atmosphere makes everything dangerously flammable. Even the wet vegetation can burst into explosive flame with the slightest spark.
#Scott, A. C. (2024): Fire in the Carboniferous earth system. Evolving Earth, Vol. 2
https://www.sciencedirect.com/science/article/pii/S2950117224000141
Quote: “The Carboniferous is the first geological Period to experience extensive wildfire. A combination of the diversification of land vegetation and its spread into all major terrestrial settings and the rise in atmospheric oxygen paved the way for the development of significant wildfire occurrence that had a significant impact upon the global Earth system.”
—You wake up in the Early Devonian 400 million years ago. Much of the planet is covered in shallow seas, while the land is mostly rocky plains and mountains broken by braided rivers and mudflats.
#Britannica (retrieved 2025): Devonian geology
https://www.britannica.com/science/Devonian-Period
“The northern portion of the combined landmass gave rise to widespread areas of continental desert, playa, and alluvial plain deposits that form one of the earliest documented large areas of nonmarine sedimentation. These terrestrial deposits, known as the Old Red Sandstone, covered much of the then-united areas of North America, Greenland, Scandinavia, and the northern British Isles.
— For about 100 million years life has begun to break down hard rocks into soil – a soft layer that enables plants to grow and life thrive.
The formation of the first soils is not a clearly defined process. It is strongly linked to the emergence of the first life and the increasing complexity of these. The first deposits of organic material and sediments during the Precambrian era could be regarded as the precursors of soils while the earliest proper soils formed during the late Precambrian era (over 500 million years ago) through the weathering of rocks by microorganisms, such as bacteria and lichens. These processes created proto-soils by releasing minerals and adding organic matter, laying the foundation for land ecosystems and the later evolution of plants.
#Ponomarenko, A.G. (2015): Early Evolutionary Stages of Soil Ecosystems. Biology Bulletin Reviews, Vol. 5 (3)
https://www.researchgate.net/publication/310804432_Early_evolutionary_stages_of_soil_ecosystems
Quote: “Newly formed deposits rich in organic matter and biophilous elements are described as soils, though they were not soil as an integral bioinert body. The Neoarchean (2.7–2.6 billion years ago) paleosoils are described in South Africa. They are rich in organic matter formed by a microbe mat, which is supported by the ratio of the biophilous elements in it (Watanabe et al., 2000).
(...)
Arthropods lose their status of the main filtration organisms of marine ecosystems, but they invade the continents, where they become the main decomposers of organic matter. They transform the living and buried organic matter of the mats and mix it with weathering products, thus becoming the most important soilforming agents, together with oligochaetes. It should be pointed out that this happened prior to the appearance of the vas cular plants, which is usually associated with the beginning of the soilforming process. Though the Archean land deposits, which were rich in organic matter, were described as soil (Watanabe et al., 2000, 2004), they were hardly a true soil, i.e., a sufficiently homogenic bioinert system.
(...)
By the appearance of vascular plants late in the Early Paleozoic, soil fauna composed of bacteria, pro tozoa (testate amoebas), fungi, and invertebrates (oli gochaetes, euthycarcinoids, myriapods, acaridae, and other arachnids) was almost formed, and the soil forming process was considerably enhanced. The Lower Devonian deposits are characterized by a rise in the number and diversity of detritus consumers, particularly collembolans and acaridae (Fig. 3).”
#Mergelov, N. et al. (2018): Alteration of rocks by endolithic organisms is one of the pathways for the beginning of soils on Earth. Nature Scientific Reports, Vol. 8, (3367)
https://www.nature.com/articles/s41598-018-21682-6#Abs1
Quote: “Although the new knowledge on Proterozoic and Archaean paleosols1,2,3,4 is continuously arising the understanding of initial stages of soil production from hard rock in a prokaryotic biosphere is scarcely replenished by the new data due to extremely low preservation potential of these early phases. Initial soil-like bodies containing biotic components possibly emerged from cyanobacteria and archaea organism-to-mineral interactions accompanied by an ensemble of abiotic weathering agents. Cyanobacteria as the first biotic component in ecosystems on land are evidenced by microfossil and geochemical records including organic molecular signatures that date back to at least 2.7 Gyr ago (Ga)5,6. The fossil land plants and fungi appeared ~0.48–0.46 Ga, whereas protein sequence analyses indicated that green algae and fungi were already present by 1 Ga and land plants appeared by 0.7 Ga7. Thus, for nearly 2 Gyr8 the terrestrial organic carbon (OC) pools were fueled by cyanobacteria, algae and lichens on later stages, and lacked any contribution from vascular plants arguably known as main sources of soil organic matter. The soils formed through interactions with these cryptogamic and microbial photoautotrophs were probably among the most long-living types of bio-abiotic systems in the Earth’s history9.”
— The ozone layer is slowly building up, fed by organisms releasing gases. Recently this process has been speeding up, the land is turning from toxic to semi habitable.
The formation of the ozone layer is directly linked to the rise of oxygen because ozone (O₃) is produced from molecular oxygen (O₂). UV radiation splits O₂ into atomic oxygen (O), which then reacts with more O₂ to form O₃.
Early land plants increased atmospheric oxygen levels by significantly enhancing organic carbon burial, which is the primary long-term source of O₂. They also accelerated phosphorus weathering, boosting photosynthesis and further driving oxygen production, leading to a sustained rise in O₂ during the Paleozoic.
#Deitrick, R. & Goldblatt, C. (2023): Effects of ozone levels on climate through Earth history. Climate of the Past, Vol. 19
https://cp.copernicus.org/articles/19/1201/2023/cp-19-1201-2023.pdf
Quote: “Ozone has several contrasting radiative effects. It absorbs strongly in the UV around 0.2 to 0.3 µm (see, e.g., Petty, 2006). This absorption (of solar UV light) occurs primarily in the stratosphere, where ozone abundance is greatest, and causes the temperature inversion there. The warmer upper atmosphere weakens the greenhouse effect provided by water and CO2 because warmer gases emit more radiation to space. In addition, ozone absorbs thermal radiation from Earth’s surface and lower atmosphere around 9.6 µm, and thus it contributes its own greenhouse effect. Further, by altering the vertical temperature structure, ozone alters the abundances of water in both its condensed and vapor forms. In turn, this affects climate through the greenhouse effect of water vapor and clouds and the albedo (reflectivity) of clouds. Ozone is produced in Earth’s atmosphere through photochemistry: molecular oxygen is broken up by solar UV photons shortward of 0.2 µm, after which the atomic oxygen reacts with molecular oxygen to form ozone, or O3 (Chapman, 1930). Therefore, the history of ozone is intimately connected to the history of molecular oxygen.
(...)
For the first ∼ 2 billion years of Earth’s history (the Hadean and Archean eons), tropospheric oxygen was present only in abundances of . 10−7 parts per volume, insufficient for an ozone layer to form (Zahnle et al., 2006; Lyons et al., 2014; Catling and Zahnle, 2020).
(...)
The Archean ended roughly 2.4 billion years ago with the largest chemical change the atmosphere has ever experienced: the Great Oxidation Event (GOE), during which molecular oxygen rose to levels of ∼ 0.001 to 0.01 (Zahnle et al., 2006; Lyons et al., 2014; Catling and Zahnle, 2020). The ozone layer, which today provides a protective shield from harmful UV radiation, first formed during this event (Ratner and Walker, 1972; Walker, 1978a, b), though it was probably weaker and lower in the atmosphere (Levine et al., 1979; Kasting and Donahue, 1980; Garduno Ruiz et al., 2023).1 During the Proterozoic, the oxygen and ozone levels stayed broadly within these levels (Lyons et al., 2014). A second rise in oxygen occurred at the end of the Proterozoic Eon and beginning of the Phanerozoic Eon, bringing oxygen up to percent levels (Lyons et al., 2014). Finally, recent work suggests an additional Paleozoic oxidation event that brought oxygen to approximately modern levels, around 20 % (Krause et al., 2018; Alcott et al., 2019). At this time, the ozone column became thicker, and the peak abundance moved upward to create the familiar structure of the stratosphere (Levine et al., 1979; Kasting and Donahue, 1980; Garduno Ruiz et al., 2023).”
#Lentona, T. M. et al. (2016): Earliest land plants created modern levels of atmospheric oxygen. PNAS, Vol 113 (35)
https://www.pnas.org/doi/pdf/10.1073/pnas.1604787113
Quote: “Here we show that the earliest plants, which colonized the land surface from ∼470 Ma onward, were responsible for this mid-Paleozoic oxygenation event, through greatly increasing global organic carbon burial— the net long-term source of O2. We use a trait-based ecophysiological model to predict that cryptogamic vegetation cover could have achieved ∼30% of today’s global terrestrial net primary productivity by ∼445 Ma. Data from modern bryophytes suggests this plentiful early plant material had a much higher molar C:P ratio (∼2,000) than marine biomass (∼100), such that a given weathering flux of phosphorus could support more organic carbon burial. Furthermore, recent experiments suggest that early plants selectively increased the flux of phosphorus (relative to alkalinity) weathered from rocks. Combining these effects in a model of long-term biogeochemical cycling, we reproduce a sustained +2‰ increase in the carbonate carbon isotope (δ13C) record by ∼445 Ma, and predict a corresponding rise in O2 to present levels by 420–400 Ma, consistent with geochemical data. This oxygen rise represents a permanent shift in regulatory regime to one where fire-mediated negative feedbacks stabilize high O2 levels.”
—The air feels thin with only 15% oxygen compared to today’s 21. Each breath feels shallow and unsatisfying, making you slightly dizzy. You are on the verge of passing out and can only move slowly.
#Lenton, T. M. et al. (2016): Earliest land plants created modern levels of atmospheric oxygen. PNAS, Vol 113 (35)
https://www.pnas.org/doi/pdf/10.1073/pnas.1604787113
Quote: “The first appearance of fossil charcoal in the Late Silurian (11) and its ongoing occurrence through the Devonian (12) (Table S1), albeit rare and at low concentrations, indicates O2 > 15–17% (vol) of the atmosphere (13) (or O2 > ∼0.7 PAL assuming a constant N2 reservoir) already by ∼420–400 Ma.”
Brand, U. et al. (2021): Atmospheric oxygen of the Paleozoic. Earth-Science Reviews Vol. 216
https://www.sciencedirect.com/science/article/pii/S0012825221000593
—At least it is currently moderately warm and not stormy.
#Judd, J. E. et al. (2024): A 485-million-year history of Earth’s surface temperature. Science, Vol. 385 (6715) https://www.science.org/doi/10.1126/science.adk3705
#Scotese, C. R. et al. (2021): Phanerozoic paleotemperatures: The earth’s changing climate during the last 540 million years. Earth-Science Reviews, Vol. 215
https://www.sciencedirect.com/science/article/abs/pii/S0012825221000027
—But it's what dominates these lands that makes this world truly alien. Reaching up to 8 meters into the sky are massive obelisks of fungal Prototaxites.
#Vajda, V. (2023): Prototaxites reinterpreted as mega-rhizomorphs, facilitating nutrient transport in early terrestrial ecosystems. Canadian Journal of Microbiology, Vol. 69 (1)
https://www.researchgate.net/publication/366262513_Prototaxites_reinterpreted_as_mega-rhizomorphs_facilitating_nutrient_transport_in_early_terrestrial_ecosystems
Quote: “One such organism was Prototaxites loganii Dawson. This puzzling fossil represents an organism that inhabited the late Silurian to Late Devonian terrestrial landscape (420–370 Ma). It was by far the largest land-living organism at the time, and possibly represented an important carbon source for the early fauna that otherwise only shared the eco-space with minute early land plants and arthropods (Retallack 2001; Hagström and Mehlqvist 2012).
(...)
The fossils are remarkably robust, reaching tree size (up to 8 m long and 1 m in diameter), in some cases branching distally, and incorporating concentric layers of longitudinally aligned, smooth, slender tubes interwoven with differentially thickened, banded tubes (Schweitzer 1983).
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The suggested affinities of these fossils have, over the past 160 years, included the trunks of vascular plants (Dawson 1859), kelp-like aquatic algae (Schweitzer 1983), or rolled up mats of liverworts (Graham et al. 2010). Hueber (2001) interpreted Prototaxites as a giant sporomorph of basidiomycote affinities, whereas Retallack and Landing (2014) favoured a provisional assignment to Glomeromycota. Honegger et al. (2018) described P. loganii as a giant sporophore (basidioma) and identified fertile Prototaxites taiti in Rhynie cherts. Boyce et al. (2007) obtained variable δ13C isotope values from Prototaxites, suggesting heterotrophic nutrition on isotopically distinct substrates consistent with a fungal affinity. Most recent interpretations have converged on Prototaxites being either a fungal fruiting body or large lichen (Selosse 2002; Nelsen and Boyce 2022).”
#Hueber, F.M. (2001): Rotted wood–alga–fungus: the history and life of Prototaxites Dawson 1859. Review of Palaeobotany and Palynology, Vol. 116 (1–2)
https://www.sciencedirect.com/science/article/abs/pii/S0034666701000586
—Between the fungal towers, there is a carpet of smaller fungi and a few alien-like primitive plants – no flowers, no leaves, just strange green stalks and fern-like structures that barely reach your ankles
#Neil, N.S. et al. (2021):The Devonian landscape factory: plant–sediment interactions in the Old Red Sandstone of Svalbard and the rise of vegetation as a biogeomorphic agent. Journal of the Geological Society, Vol. 178 (5)
https://pubs.geoscienceworld.org/gsl/jgs/article-abstract/178/5/jgs2020-225/595646/The-Devonian-landscape-factory-plant-sediment?redirectedFrom=PDF
Quote: “These contributions to the operation of continental landscapes were absent for most of Earth’s history and thus establishing a timeline for their origin and radiation is essential for understanding the mechanistic evolution of the planet’s surface. A consensus has arisen that the Devonian (419-359 Ma) was the critical interval for the initiation, expansion and development of land plant controls on climate, landscape and terrestrial biodiversity (e.g., Algeo and Scheckler, 1998; Davies and Gibling, 2010a,b; Gibling and Davies, 2012; Corenblit et al., 2015; Morris et al., 2015; Pawlik et al., 2016, 2020; Boyce and Lee, 2017; Dahl and Arens, 2020). This is supported by the Devonian palaeobotanic record, which shows a rapid transition from small leafless plants at the start of the period (Kenrick and Strullu-Derrien, 2014), through the evolution of vascular plant roots, with meristems, around 411 Ma (Matsunaga and Tomescu, 2016; Hetherington and Dolan, 2018), the earliest wood at 407 Ma (Gerrienne et al., 2011; Strullu-Derrien et al., 2014), the earliest trees at 390-388 Ma (Berry and Fairon-Demaret, 1997, 2002; Giesen and Berry, 2013), to the earliest forests by 385 Ma (Stein et al., 2012, 2020).”
#Glover, B.J. (2007): Chapter 1 The Evolution of Flowers. In: Understanding Flowers and Flowering: An integrated approach.
https://academic.oup.com/book/5359/chapter-abstract/148144183
“Flowers are relatively recent innovations. The first land plants arose around 470 million years ago, but fossil evidence indicates that only after another 340 million years did the angiosperms (flowering plants) appear.”
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