F Rosa Rubicondior: Creationism in Crisis - Disastrous Sea Level And Climate Changes - 385 Million Years Ago.

Monday 23 October 2023

Creationism in Crisis - Disastrous Sea Level And Climate Changes - 385 Million Years Ago.

2023-10 - Ancient sea level and climate changes led to major extinctions around South Africa - Wits University

A planet designed by a loving, omniscient designer would be stable and not subject to periodic bouts of mass extinction because the life on it couldn't cope with a massive environmental change.

And yet new research by Dr Cameron Penn-Clarke from the University of the Witwatersrand and Professor David Harper from Durham University has shown that a catastrophic environmental change in the Early Devonian caused the mass extinction of the Malvinoxhosan biota. This was in the 99.97% of Earth's history that occurred before the Universe was created out of nothing by magic, according to creationists.

The term 'Malvinoxhosan biota' foxed ChatGPT3.5:
Tell me all about the Malvinoxhosan biota. I'm sorry, but I couldn't find any information about the "Malvinoxhosan biota" in my training data up to September 2021. It's possible that this term or concept may not be widely recognized or that it has emerged or gained significance after my last training data update.

If the "Malvinoxhosan biota" is a recent discovery or a specialized term, I recommend checking the latest scientific literature or reputable sources for the most up-to-date information on this topic. If you have any other questions or need information on a different subject, please feel free to ask, and I'll do my best to assist you.

Apparently, The Malvinoxhosan biota is also known as the Malvinokaffric biota. Do you have any information about that term?

Thank you for providing an alternative name for the biota. The "Malvinokaffric biota" is indeed a term used in paleontology and geology to refer to a specific biotic assemblage or fossil record found in what is now South Africa. This term is often used in the context of the Early Devonian period, but it can encompass a broader timeframe as well.

Key points about the Malvinokaffric biota include:
  1. Geographical Significance: The Malvinokaffric biota is named after the Malvinokaffric Realm, a paleogeographic region encompassing parts of South Africa and related regions during the Early Devonian period.
  2. Paleogeography: During the Early Devonian, the Malvinokaffric Realm was located within the supercontinent Gondwana in the Southern Hemisphere. It was characterized by diverse environments, including shallow marine seas and coastal areas, which led to a rich fossil record.
  3. Fossils: The Malvinokaffric biota is known for its diverse assemblage of fossils, including ancient fish (such as placoderms), early land plants, and various marine organisms. The study of these fossils has provided valuable insights into the evolution of life during this time, including the transition from aquatic to terrestrial ecosystems.
  4. Scientific Significance: The Malvinokaffric biota is significant in the field of paleontology because it contributes to our understanding of the early history of vertebrates and the development of terrestrial ecosystems. Fossils from this biota have helped scientists trace the origins of jawed vertebrates and the colonization of land by plants.
  5. Fossil Sites: Fossil-bearing rock formations that contain Malvinokaffric biota fossils can be found in various locations in South Africa, particularly in regions with Early Devonian sedimentary rocks.

The Malvinokaffric biota, also known as the Malvinoxhosan biota, is an important area of study for scientists interested in the history of life on Earth, especially during the Early Devonian period. Researchers continue to make new discoveries and gain insights into the evolution of life during this time through the examination of fossils and geological formations associated with this biota.

Do you have information about the Early Devonia period in what is now South Africa?

The Early Devonian period in what is now South Africa is a fascinating geological and paleontological time frame. During this period, which occurred approximately 419 to 393 million years ago, South Africa was part of the supercontinent Gondwana, situated in the Southern Hemisphere. The Early Devonian was a critical time in Earth's history when complex terrestrial ecosystems began to develop. Here are some key points about the Early Devonian in South Africa:
  1. Geological Context: South Africa during the Early Devonian was characterized by diverse geological features, including continental shelves, shallow seas, and sedimentary basins. These environments played a crucial role in the formation of fossil-bearing rock layers.
  2. Paleogeography: During the Early Devonian, South Africa was located near the South Pole of Gondwana, and the climate was significantly different from today's. It experienced a cooler climate with polar ice caps and glacial periods.
  3. Fauna: The Early Devonian was marked by the diversification of life. In South Africa, one of the notable groups of organisms was the jawed fishes, which are considered the ancestors of all modern vertebrates. The famous placoderm fish, Dunkleosteus, is one of the well-known examples from this period.
  4. Plant Life: The Early Devonian also saw the emergence of complex land plants. Fossils of early vascular plants, such as Cooksonia, are found in South African rock layers, marking an important step in the colonization of land by plants.
  5. Climate Change: The Early Devonian experienced significant climate changes, including glaciation events. These climate fluctuations had an impact on both marine and terrestrial ecosystems.
  6. Fossils and Geological Sites: South Africa is known for its rich fossil record from the Early Devonian period. Fossils of ancient fish, early land plants, and other organisms have been discovered in various locations within the country. For example, the Witteberg Group in the Eastern Cape and the Bokkeveld Group in the Western Cape are known for their Early Devonian fossil deposits.
  7. Research and Scientific Significance: The study of Early Devonian rocks and fossils in South Africa has contributed to our understanding of the evolution of life on Earth, particularly the transition from aquatic to terrestrial environments and the emergence of vertebrates.

Overall, the Early Devonian period in what is now South Africa offers a window into a dynamic and transformative time in Earth's history, marked by the diversification of life forms and the initial steps in the conquest of land by plants and animals. Researchers continue to explore this period, unearthing new insights and discoveries.
One of the, until now unsolved, mysteries of paleobiology is what caused the mass extinction of the Malvinoxhosan biota. The pair of researchers have published their findings, open access, in the journal Earth-Science Reviews. Its significance is explained in a Witwatersrand University press release:
Ancient sea level and climate changes led to major extinctions around South Africa

Sea level and climate changes altered the marine ecosystems at the South Pole 390-385 million years ago.

New research by Dr Cameron Penn-Clarke from the University of the Witwatersrand and Professor David Harper from Durham University reveals a chain of environmental disasters. These took place in what is today's South Africa, during an ancient time period called the Early-Middle Devonian. The crises led to the extinction of a unique group of marine animals called the Malvinoxhosan biota. This groundbreaking study published in Earth-Science Reviews is the first to document such large-scale extinction event of this nature and magnitude in South Africa, adding to growing evidence that changes in climate and sea levels can have global consequences—even in areas near the South Pole.

During the Early-Middle Devonian period, a large landmass called Gondwana—which included parts of today's Africa, South America, and Antarctica—was located near the South Pole. Unlike today's icy conditions, the climate was warmer, and the sea levels were higher, flooding most of the land.

The Malvinoxhosan biota were a group of marine animals that thrived in cooler waters. They included various types of shellfish, many of which are now extinct. "The origin and disappearance of these animals have remained an enigma for nearly two centuries until now," says Dr. Penn-Clarke.

The researchers collected and analysed a vast amount of fossil data. They used advanced data analysis techniques to sort through layers of ancient rock based on the types of fossils found in them. Imagine it like sorting through layers of a cake, each with different ingredients. They then identified at least 7 to 8 distinct layers, each showing fewer and fewer types of marine animals over time. These findings were then compared with how the environment and sea levels have changed, as well as with global temperature records from that ancient period. They found that these marine animals went through several phases of declining numbers of different species, which correlated with changes in sea levels and climate. It was a difficult process. "This research is around 12-15 years in the making, and it wasn’t an easy journey," shares Dr. Penn-Clarke. "I was only able to overcome all the different challenges through dogged persistence and perseverance."

Their research suggests that the Malvinoxhosan biota survived during a long period of global cooling. Dr Penn-Clarke elaborates, "We think that cooler conditions allowed for the creation of circumpolar thermal barriers—essentially, ocean currents near the poles—that isolated these animals and led to their specialisation." As the climate warmed up again, these animals disappeared. They were replaced by more generalist marine species that are well-adapted to warmer waters. Shifts in sea levels during the Early-Middle Devonian period probably disrupted natural ocean barriers that had kept waters cooler at the South Pole. This allowed warmer waters from regions closer to the equator to flow in, setting the stage for marine animals that thrive in warmer conditions to move into these areas. As a result, these warm-water species gradually took over, leading to the decline and eventual disappearance of the specialized, cool-water Malvinoxhosan marine animals.

The extinction of the Malvinoxhosan biota led to a complete collapse in polar ecosystems, as biodiversity in these regions never recovered. "This suggests a complete collapse in the functioning of polar environments and ecosystems to the point that they could never recover," Dr. Penn-Clarke adds. He likens this research to playing a game of Cluedo. “It's a 390-million-year-old murder mystery. We now know that the combined effects of changes in sea-level and temperature were the most likely 'smoking gun' behind this extinction event", he notes. It is still unknown if this extinction event can be correlated with known extinction events at the same time elsewhere during the Early-Middle Devonian as researchers simply do not have any real good age inferences. The mystery deepens further, and it is far from over.

Interestingly, similar declines in biodiversity controlled by sea-level changes have been observed in South America. This points to a broader pattern of environmental change affecting the South Polar region during this period and underscores the vulnerability of polar ecosystems, even in the past. "This research is important when we consider the biodiversity crisis we are facing in the present day," says Dr. Penn-Clarke. "It demonstrates the sensitivity of polar environments and ecosystems to changes in sea level and temperature. Any changes that occur are, unfortunately, permanent."
Technical details are given in the researchers' open access paper:

Global reconstructions, inclusive of environments and ecosystems, and biodiversity counts for the Devonian Period are often done so at the expense of high latitude regions given a historical lack of data presented from these areas. This has bearing on the recognition of biocrises (events marked by extinctions and faunal turnovers) at high latitudes as well as their controls and potential correlation with global, regional, and local tempos. The appearance and disappearance of high-latitude endemic Malvinoxhosan (synonymous with the “Malvinokaffric Realm” which it supersedes) marine invertebrate faunas from West Gondwana are often overlooked, in part owing to difficulties in correlating fossil-bearing strata with global frameworks given the absence and rarity of several key index taxa as well as detailed biostratigraphic appraisals in which to draw regional interbasinal correlations and comparisons. The Early to Middle Devonian Series of South Africa (upper Table Mountain, Bokkeveld and lower Witteberg groups) are a classic Malvinoxhosan-bearing section recording the rise of these endemic faunas, as well as their decline and replacement by cosmopolitan faunas. A detailed biostratigraphy of this interval was created following an assessment of fossil material curated at the Council for Geoscience and Iziko South African Museum, Cape Town as well as from literature. These data suggest that the Malvinoxhosan bioregion persisted as a cohesive unit during Rietvlei-Baviaanskloof to Waboomberg deposition (Pragian/Emsian-early Givetian) given that many representative taxa are found in these strata, however showing a trend of decreasing diversity with little origination through time. Above this interval, few representative taxa are known to continue into the upper Bokkeveld and Witteberg groups, disappearing entirely by the deposition of the Blinkberg Formation. The few fossils that are known in these strata and those succeeding it (e.g., the Swartruggens Formation) are entirely cosmopolitan in identity. Using novel multivariate statistical methods (non-metric multidimensional scaling and cluster analysis) in conjunction with network analysis (NA), the data were interrogated to indicate potential groupings of strata according to their fossil content as well as to track faunal changes through time. These analyses suggest the presence of at least seven to eight interval assemblage biozones housed within at least three larger faunal complexes (Eo-Malvinoxhosan, Malvinoxhosan and Post-Malvinoxhosan) based on their constituent faunal makeup. A closer inspection of these faunal complexes and interval assemblage biozones show a stepped decline in biodiversity with little to no origination and recovery through time that may be correlated with local base-level change at varying orders of magnitude. Declines in biodiversity show selectivity for taxa with epifaunal and semi-infaunal habits with respect to infaunal, deep infaunal and nektonic taxa. Environmental conditions associated with the collapse of the Malvinoxhosan bioregion are thought to have been catastrophic as few new (often short-ranging) immigrants are registered in Post-Malvinoxhosan strata. Further to this, those faunas that are prevalent in Post-Malvinoxhosan strata (e.g., Tropidoleptus) those with known high environmental tolerance and were already present in the region prior to the collapse of the Malvinoxhosan bioregion. Lastly, the observed biodiversity changes in South Africa with respect to local base-level show remarkable similarities with several time equivalent locales in South America suggesting that the decline and extinction of the Malvinoxhosan biota was regional and that the biostratigraphy presented herein has regional application. Here, it is thought regional tectonic controls are suggested to have brought on sea-level changes and entrained warmer waters into higher latitudes against the backdrop of overall rising temperatures from the late Givetian onwards. Whilst the decline of the Malvinoxhosan bioregion might associated with global Middle Devonian biocrises (e.g., Kačák; Taghanic) insufficient age constraints for these strata are available at present to make direct comparisons. Furthermore, an adequate driver for global sea-level change during the Devonian Period, needs to be established to tease out global and local signals in constructed local sea-level curves to establish if these changes (and their effects in changes in biodiversity) are truly global in extent.
Fig. 1. Palaeobiogeography of West Gondwana during the Early Devonian (Late Emsian) showing peak extent of the Malvinoxhosan bioregion at high latitudes in the vicinity of the South Pole (70°-90° S) after Penn-Clarke and Harper (2021). Bordering the Malvinoxhosan bioregion are the Amazonian and Colombian-West African bioregions that largely equate with the Eastern Americas and Old-World Realms. These distinct bioregions persisted during a period of protracted cooling during the Pragian-Givetian, collapsing and resulting in a more cosmopolitan regime from the late Givetian onwards with rising global temperatures, after Joachimski et al. (2009). Abbreviations: Ac- Accraian (Ghana), Am- Amazonas (Brazil), Bo- Bové (Guinea, Guinea-Bissau, Senegal), Ca- Cape (South Africa), Ch- Chaco/Central Andean (Bolivia), FB- Fox Bay (Falkland Islands), Ll- Llanos (Colombia and Venezuela), NS- “North Saharan” (Tindouf, Ghadamis, Polignac, Murzuq basins), Pa- Paraná (Brazil, Paraguay, Uruguay), Px- Parecis (Brazil), Pr- Precordillera (western Argentina), Pn- Parnaíba (Brazil), SP- southern Peru, SS- “South Saharan” (Tamesna and Taoudeni basins and Adrar, Hodh regions), Su- Suwannee (Florida, Georgia, United States), Ve- Ventana (eastern Argentina), WA- West Antarctica (“Ellsworth-Whitmore Mountains”), Zo- Zorritas (northern Chile).
Penn-Clarke, Cameron R.; Harper, David A.T.
The rise and fall of the Malvinoxhosan (Malvinokaffric) bioregion in South Africa: Evidence for Early-Middle Devonian biocrises at the South Pole
Earth-Science Reviews 246 104595. DOI: 10.1016/j.earscirev.2023.104595

Copyright: © 2023 The authors.
Published by Elsevier B.V.. Open access.
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)
The picture is one of a planet in dynamic, even chaotic, flux in which landmasses form, break up and move over the surface, creating warm, shallow seas which then cool or close up, and of a changing climate in which Earth heats up and cools as the continents move around and ocean currents change, or the levels of greenhouse gasses change in response to tectonic activity and biological activity, and the energy output from the sun fluctuates according to long-term solar cycles.

These changes cause new niches to open up allowing new taxons to evolve and diversify, only to be exterminated at a later stage.

This is not the sort of planet that could possibly have been created by a loving, omniscient god who knows exactly what the future holds for the life-forms it creates but creates them anyway. And to make matters worse for creationists, the geological, climatological and archaeological evidence is that this all happened in the 99.97% of Earth history that should not have happened according to creationist dogma and the tales they rely on from their ancient 'science text-book' written by scientifically-illiterate Bronze Age hill famers, who believed Earth was small, flat, had a dome over it and stood at the centre of the Universe.

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