The synapsid Lystrosaurus survived the mass extinction and came to dominate the landscape later.
Julio Lacerda
Creationist claims that Earth was created perfectly designed for life (especially their life) are farcical and can only be believed by people carefully ignorant of the facts.
Of course, insisting that Earth is merely a few thousand years old, makes it easier to dismiss the 99.9975% of it that proves them wrong.
In my previous post I wrote about a newly-discovered trilobite with an additional pair of legs, and the reason we don't have them scuttling over marine sediment any more is because Earth turned against them when a climate catastrophe caused a marine catastrophe, depriving the oxygen-dependent organism's living in it of oxygen. This was one of the so-called Oceanic Deoxygenation Events.
That explains the mass extinction of marine life, but the question is, why did it also cause a terrestrial mass extinction of comparative severity?
What information do you have about the Permian-Triassic mass extinction 252 million years ago? The Permian-Triassic mass extinction (also called the Great Dying) occurred about 252 million years ago and is the most severe extinction event in Earth's history, wiping out around 90-96% of all marine species and 70% of terrestrial vertebrates. It marks the boundary between the Permian and Triassic periods and the end of the Paleozoic Era.Now a team of researchers co-led by the University of Bristol and China University of Geosciences (Wuhan) scientists, Dr Alexander Farnsworth and Professor Yadong Sun respectively, believe they have found the answer.
Key Causes (Hypotheses):Consequences:
- Volcanic Activity:
The Siberian Traps, a massive region of volcanic rock in what is now Siberia, experienced prolonged volcanic eruptions. These eruptions released vast amounts of CO₂, methane, and sulfur dioxide into the atmosphere, leading to severe global warming and acid rain.- Ocean Anoxia:
Global warming caused by volcanic emissions may have reduced the oxygen levels in the oceans (anoxia), making them inhospitable for marine life. Ocean acidification, driven by increased CO₂, further damaged marine ecosystems.- Methane Release:
Melting of methane clathrates (frozen methane deposits) in ocean floors may have released huge amounts of methane, amplifying global warming.- Climate Change:
The combination of volcanic gases and methane likely led to a runaway greenhouse effect, with average temperatures rising significantly. This created extreme environmental stress for many species.- Other Factors:
Some research suggests additional potential triggers, including asteroid impacts or widespread wildfires, but volcanic activity and climate change remain the dominant theories.
- Marine Life:
The extinction devastated marine life, including trilobites (which were already declining but went extinct), brachiopods, corals, and other invertebrates. Reef ecosystems collapsed entirely.- Terrestrial Life:
On land, many species of synapsids (ancestors of mammals), amphibians, and insects were wiped out. The dominant land vertebrates before the extinction were pelycosaurs and therapsids (mammal-like reptiles), many of which perished.- Recovery:
The biosphere took millions of years to recover, with the Triassic Period witnessing the rise of archosaurs (precursors to dinosaurs and birds) and the evolution of early mammals.
The Permian-Triassic extinction had a profound impact on the evolution of life on Earth, shaping future ecosystems and paving the way for the dominance of dinosaurs in the Mesozoic Era.
The team has just published their findings in the journal Science and explained it in a Bristol University News item:
New research reveals how El Nino caused the greatest ever mass extinction
Mega ocean warming El Niño events were key in driving the largest extinction of life on planet Earth some 252 million years ago, according to new research.
The study, published today in Science and co-led by the University of Bristol and China University of Geosciences (Wuhan), has shed new light on why the effects of rapid climate change in the Permian-Triassic warming were so devastating for all forms of life in the sea and on land.
Scientists have long linked this mass extinction to vast volcanic eruptions in what is now Siberia. The resulting carbon dioxide emissions rapidly accelerated climate warming, resulting in widespread stagnation and the collapse of marine and terrestrial ecosystems.
But what caused life on land, including plants and usually resilient insects, to suffer just as badly has remained a source of mystery.
Climate warming alone cannot drive such devastating extinctions because, as we are seeing today, when the tropics become too hot, species migrate to the cooler, higher latitudes. Our research has revealed that increased greenhouse gases don’t just make the majority of the planet warmer, they also increase weather and climate variability making it even more ‘wild’ and difficult for life to survive.
Dr Alexander Farnsworth, Co-lead author
Senior Research Associate
University of Bristol, Bristol, UK.
The Permian-Triassic catastrophe shows the problem of global warming is not just a matter of it becoming unbearably hot, but also a case of conditions swinging wildly over decades.
The scale of Permian-Triassic warming was revealed by studying oxygen isotopes in the fossilised tooth material of tiny extinct swimming organisms called conodonts. By studying the temperature record of conodonts from around the world, the researchers were able to show a remarkable collapse of temperature gradients in the low and mid latitudes.Most life failed to adapt to these conditions, but thankfully a few things survived, without which we wouldn’t be here today. It was nearly, but not quite, the end of the life on Earth.
Professor Yadong Sun, co-lead author
State Key Laboratory of Biogeology and Environmental Geology
China University of Geosciences (Wuhan)
Wuhan, Peoples' Republic of China.
Dr Farnsworth, who used pioneering climate modelling to evaluate the findings, said:
Essentially, it got too hot everywhere. The changes responsible for the climate patterns identified were profound because there were much more intense and prolonged El Niño events than witnessed today. Species were simply not equipped to adapt or evolve quickly enough.
Dr Alexander Farnsworth.
In recent years El Niño events have caused major changes in rainfall patterns and temperature. For example, the weather extremes that caused the June 2024 North American heatwave when temperatures were around 15°C hotter than normal. 2023-2024 was also one of the hottest years on record globally due to a strong El Niño in the Pacific, which was further exacerbated by increased human-induced CO2 driving catastrophic drought and fires around the world.
The results of the climate modelling also help explain the abundant charcoal found in rock layers of that age.Fortunately such events so far have only lasted one to two years at a time. During the Permian-Triassic crisis, El Niño persisted for much longer resulting in a decade of widespread drought, followed by years of flooding. Basically, the climate was all over the place and that makes it very hard for any species to adapt.
Professor Paul Wignall, co-author
Professor of Palaeoenvironments
School of Earth and Environment
University of Leeds, Leeds, UK.
The researchers observed that throughout Earth’s history there have been many volcanic events similar to those in Siberia, and many caused extinctions, but none led to a crisis of the scale of the Permian-Triassic event.Wildfires become very common if you have a drought-prone climate. Earth got stuck in a crisis state where the land was burning and the oceans stagnating. There was nowhere to hide.
Professor David P. G. Bond, co-author
School of Environmental Sciences
University of Hull, Hull, UK.
They found Permian-Triassic extinction was so different because these Mega-El Niños created positive feedback on the climate which led to incredibly warm conditions starting in the tropics and then beyond, resulting in the dieback of vegetation. Plants are essential for removing CO2 from the atmosphere, as well as the foundation of the food web, and if they die so does one of the Earth's mechanisms to stop CO2 building up in the atmosphere as a result of continued volcanism.
This also helps explain the conundrum regarding the Permian-Triassic mass extinction whereby the extinction on land occurred tens of thousands of years before extinction in the oceans.
Mass extinctions, although rare, are the heartbeat of the Earth’s natural system resetting life and evolution along different paths.Whilst the oceans were initially shielded from the temperature rises, the mega-El Nino’s caused temperatures on land to exceed most species thermal tolerances at rates so rapid that they could not adapt in time. Only species that could migrate quickly could survive, and there weren’t many plants or animals that could do that.
Professor Yadong SunPaperThe Permo-Triassic mass extinction, although devastating, would ultimately see the rise of Dinosaurs becoming the dominant species thereafter as would the Cretaceous mass extinction lead to the rise of mammals, and humans.
Dr Alexander Farnsworth.
AbstractJust another example of how Earth can become a very hostile place for life; far from the idyllic, perfectly designed place that parochial creationists like to delude themselves into believing their special invisible magic friend in the sky magicked up for them out of nothing.
The ultimate driver of the end-Permian mass extinction is a topic of much debate. Here, we used a multiproxy and paleoclimate modeling approach to establish a unifying theory elucidating the heightened susceptibility of the Pangean world to the prolonged and intensified El Niño events leading to an extinction state. As atmospheric partial pressure of carbon dioxide doubled from about 410 to about 860 ppm (parts per million) in the latest Permian, the meridional overturning circulation collapsed, the Hadley cell contracted, and El Niños intensified. The resultant deforestation, reef demise, and plankton crisis marked the start of a cascading environmental disaster. Reduced carbon sequestration initiated positive feedback, producing a warmer hothouse and, consequently, stronger El Niños. The compounding effects of elevated climate variability and mean state warming led to catastrophic but diachronous terrestrial and marine losses.
Yadong Sun; Alex Farnsworth et al.
Mega El Niño instigated the end-Permian mass extinction
Science 385, 1189-1195 (2024). DOI:10.1126/science.ado2030
© 2024 American Association for the Advancement of Science.
Reprinted under the terms of s60 of the Copyright, Designs and Patents Act 1988.
But then the scientifically illiterate and ignorant parochial Bronze Age pastoralists who wrote their favourite source book, knew nothing of the history of life on Earth, let alone anything of the frequent climate catastrophes and mass extinctions, since they were unaware of anything more than a day or two's walk from their Middle Eastern homes.
Few things illustrate creationism's detachment from reality than the frequent mass extinctions that Earth has experienced in the long period of its history from before creationists imagine it existed, and this is just one way we can tell that whoever wrote creationism's origin myths was not an inerrant, omniscient creator god.
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