Thursday 25th of April 2024

the permian extinction...

lando
The general temperature of the planet has been slightly cooling overall with highs and lows, from about 570 million years ago till today. According to the greater cycles, it could go up again, though not as much than during some previous periods.


The natural cycles depend on many factors, yet presently one factor is rapidly warming the planet — human activity — when the planet should be slowly cooling according to the current Milankovitch cycles.

570 million years ago is when complex species started to appear in the oceans. This defines the “border" between the Cryptozoic (simple organisms: bacterias, viruses and mono-cellular soup of the oceans) and the Phanerozoic (encompassing multi-cellular life/animals/plants)

From 570 million years ago to now concerns humans existence, as life on land evolved in the Palaeozoic era (starting 541 million years ago — though, in July 2018, scientists reported that the earliest life on land may have been bacteria, 3.22 billion years ago). 

Discounting bacterias, 541 million years plus or minus a few thousand years is defined by various changes in the planetary characteristics, though it may sound a bit arbitrary to non-scientists...

There is evidence that centipede-like animals began to explore the world above water about 530 million years ago. Somewhere around 430 million years ago, plants colonised the bare earth, creating a land rich in food and resources, while reducing erosion. It was another 30 million years before prehistoric backboned fish crawled out of the water and began the evolutionary tree we sit pretty atop today. 

The Palaeozoic (meaning "ancient life") is the earliest of three major geologic eras of the Phanerozoic Eon. The other two are the Mesozoic era (median, ± 251-65.8 million) and the Cainozoic era (recent, ± 65.8-now).

The Palaeozoic is subdivided into six geological periods: the Cambrian (the Cambrian "explosion of life"), Ordovician, Silurian (these three periods with animal life in the oceans only), Devonian, Carboniferous, and the Permian (with life in the oceans and on land). The Palaeozoic thus lasted from 541 to 251.902 million years ago. This accurate latter date is a defining moment in the survival of life.

What has influenced the scientists to define these eons, eras and periods? Many factors observed in the geological structure of the rocks have led scientists to note MAJOR changes at specific timeframes. Though we weren’t there, precise studies of various radio-active decays give excellent verification of the timeframe accuracy about stratifications and upheavals. 

Some boundaries between periods are sharp due to “sudden” changes, some are more vague due to the extended time of changes. The dates are regularly revised for more precision when new evidence comes to light. 

Since the first fishy creatures slowly evolved into amphibians, there has been five MAJOR near-extinction of life that we know of. Lucky us, we’re still here, but it is debatable whether these extinction events made us more intelligent or not, for having to fight for our supper.

Let’s look at the Permian Period, the end of the Palaeozoic, in more details — as the rocks strata formed at the end of this period are being exploited for shale gas, especially in Texas, USA. Methane gas is locked away in the decomposed and stratified layers of dead matter that got collected 251 million years ago in various “basins” — those accumulations formed at the end of the Permian — when this Period ended with the greatest known mass extinction event in Earth’s history

In a blink of geological time, the majority of living species on the planet were wiped out of existence. This less than 1,000 years timeframe could be even narrower...

Scientists estimate that more than 95 percent of marine species became extinct and more than 70 percent of land animals. Fossil beds in the Italian Alps show that plants were hit just as hard as animal species. 

The average temperature of the planet had reached 32.4 degrees Celsius by 251 million years ago (the end of the Permian Period) —  losing the ice caps by around 261 million years ago — with an increase of 22.2 degrees Celsius in 19 million years. What did create the change? What did create the massive extinction? Are they related?

Evolution of plants and animals in the Permian Period (starting 286 million years ago), had had to cope with a brief 18.7 degrees Celsius polar-ice free planet (polar caps appear below 18.3 degrees Celsius on earth) with temperatures then plunging to 10 degrees Celsius by 270 million years ago and climbing back up to the massive 32.4 degrees Celsius mentioned…

Yet, this most severe mass extinction occurred with no warning signs, according to a study by scientists at MIT, China, and elsewhere. In the approximately 30,000 years leading up to the end-Permian extinction, there is no geologic evidence of species starting to die out. Researchers also found no signs of any big swings in ocean temperature nor dramatic fluxes of carbon dioxide in the atmosphere. When ocean and land species died out, they did so en masse, over a timeframe that was geologically very short.

If Gus understands the data, The average ocean temperature was 35 degrees Celsius at the surface and 30 degrees Celsius at 27 metres depth — in a period that encompasses about 30,000 years before the main extinction event. This temperature is not very significant compared with a much larger warming that took place after most species already had died out. Note that species HAD ADAPTED TO THE CHANGING CONDITIONS OVER MILLIONS OF YEARS. Suddenly something "happened"...


"Big changes in temperature come right after the extinction, when the ocean gets really hot and uncomfortable," Ramezani says. "So we can rule out that ocean temperature was a driver of the extinction.

Here we must point out that temperatures on the planet are not uniform and vary according to latitude and altitude. At this stage, it seems we do not have a full picture of temperature evidence for this event from all around the globe — except a global correlation of SUDDEN extinction in the fossil record. With a temperature average of 30 degrees, the sea level would be around 100 metres above those of now. BOOM.

Extinction would have happened more in some regions and less in others, leaving a “continuum of life” somewhere despite the destructions of most species. All along, this is about the survival of DNA, in whatever specie-format it can takes. New species thus came along after a few million years. After this event, It took about 65 million years for the climate to become cold enough to induce ice caps. by 170 million years ago the average temperature of the planet started to rise again. It reached another sharp temperature peak 95 million years ago at 28 degrees Celsius. 

So what could have caused the sudden Permian global wipeout? The leading hypothesis is that the end-Permian extinction was caused by massive volcanic eruptions. But there was extensive volcanic activity before and after the extinction, which could have caused some environmental stress and ecologic instability, but as the ecologic collapse came as a sudden blow, there is no specific smoking gun in the sediment record that points out to a cause of extinction. GUS POSTULATES THAT at this time, a massive comet landed somewhere not found yet, such as that known as Gosse’s Bluff, Australia (142 million years ago). This meteor could have been larger than the meteorite that wiped out the dinosaurs, this one having landed in Yucatan 65.8 million years ago. This is my theory... but my mind is open.

"It is even possible that the main pulse of Permian extinction occurred in just a few centuries. If it turns out to reflect an environmental tipping point within a longer interval of ongoing environmental change, that should make us particularly concerned about potential parallels to global change happening in the world around us right now.” says Jonathan Payne, professor of geological sciences and biology at Stanford University.


A vibrant marine ecosystem was continuing until the very end of Permian, and then life disappears, even in the oceans. 



We think of life as quite adaptable in general, yet “progressively” as species evolve and new one come along. Humans seem to be the most adaptable species yet. But there are times at which the environment factors become “toxic” and not liveable for all existing species. Whether these extinction events happen with cold or heat, CO2 or other gases, the key is adaptation to changes — not only the temperatures, but to the availability and the toxicity of certain resources. We know of certain natural gases and substances that can be fatal. Carbon monoxide kills quickly and leaves hardly any trace. Chlorine gas can develop naturally should the ingredients be readily available. SO2 is dangerous, NOx are not breathable  CO2 warms up the atmosphere.

We, humans, are stressing the natural parameters of the last 500,000 years of the planet history. We know this accurately. 
We have invented many chemicals that are poisons. Our emissions of methane, NOx and CO2 are beyond what the natural settings can absorb. We are polluting everything with rubbish and plastics that could last for another 10,000 years. A blink. But a long blink in human history if one is born today, yesterday or tomorrow… Sure, we will adapt to our human created crappy environmental factors, but others species won’t. The changes are becoming too “stressful” and our only way to survive might be to become wombats...

In retrospect, when I calculated a maximum of 12 degrees above present temperature average for the planet taking on board “forcing”, in 1994 — introduced on this site in 2005, making the average of around 28.5 degrees Celsius, I was optimistically below the maximum figure of 32.4 degrees Celsius WHICH CAN HAPPEN and has happened before. 

Climate change is not the issue, Global warming and its speed of change is. In about 250 years we are likely to increase the average temperature of the planet by more than 6 degrees Celsius and going beyond this. Are we game? are we prepared? DO WE UNDERSTAND THIS? 

Our scientists do. We, the bogans from the shire don’t. Next elections vote your Bogan extraordinaire, El Maestro of bullshit, Scott Morrison, OUT… Out...




GL.

anthropgenic global warming

The climate wars have reignited in the Coalition party room, with Prime Minister Scott Morrison saying he won’t be bullied into tougher action on global warming.

“We listen to Australians right across the country. Not just in the inner city,” Mr Morrison told Nine on Wednesday.

“We won’t be bullied into higher taxes or higher electricity prices.”

The PM’s tough talking came after the Nationals leadership turmoil ignited a stoush in the Coalition party room on Tuesday.

 

Read more:

https://thenewdaily.com.au/news/politics/australian-politics/2020/02/05/...

 

IDIOT...! He has not realised yet that USING RENEWABLE ENERGY will lower the cost of electricity... How bad is he?...

 

 

Read above.

 

Read also:

global warming is real and anthropogenic...

survivors and evolutionary adaptors...

 

The Triassic Period was the first period of the Mesozoic Era and occurred between 251 million and 199 million years ago. It followed the great mass extinction at the end of the Permian Period and was a time when life outside of the oceans began to diversify.

At the beginning of the Triassic, most of the continents were concentrated in the giant C-shaped supercontinent known as Pangaea. Climate was generally very dry over much of Pangaea with very hot summers and cold winters in the continental interior. A highly seasonal monsoon climate prevailed nearer to the coastal regions. Although the climate was more moderate farther from the equator, it was generally warmer than today with no polar ice caps. Late in the Triassic, seafloor spreading in the Tethys Sea led to rifting between the northern and southern portions of Pangaea, which began the separation of Pangaea into two continents, Laurasia and Gondwana, which would be completed in the Jurassic Period.


Marine life


 

The oceans had been massively depopulated by the Permian Extinction when as many as 95 percent of extant marine genera were wiped out by high carbon dioxide levels. Fossil fish from the Triassic Period are very uniform, which indicates that few families survived the extinction. The mid- to late Triassic Period shows the first development of modern stony corals and a time of modest reef building activity in the shallower waters of the Tethys near the coasts of Pangaea.


Early in the Triassic, a group of reptiles, the order Ichthyosauria, returned to the ocean. Fossils of early ichthyosaurs are lizard-like and clearly show their tetrapod ancestry. Their vertebrae indicate they probably swam by moving their entire bodies side to side, like modern eels. Later in the Triassic, ichthyosaurs evolved into purely marine forms with dolphin-shaped bodies and long-toothed snouts. Their vertebrae indicate they swam more like fish, using their tails for propulsion with strong fin-shaped forelimbs and vestigial hind limbs. These streamlined predators were air breathers and gave birth to live young. By the mid-Triassic, the ichthyosaurs were dominant in the oceans. One genus, Shonisaurus, measured more than 50 feet long (15 meters) and probably weighed close to 30 tons (27 metric tons). Plesiosaurs were also present but not as large as those of the Jurassic Period.


Plants and insects


 

Plants and insects did not go through any extensive evolutionary advances during the Triassic. Due to the dry climate, the interior of Pangaea was mostly desert. In higher latitudes, gymnosperms survived and conifer forests began to recover from the Permian Extinction. Mosses and ferns survived in coastal regions. Spiders, scorpions, millipedes and centipedes survived, as well as the newer groups of beetles. The only new insect group of the Triassic was the grasshoppers.


Reptiles


The Mesozoic Era is often known as the Age of Reptiles. Two groups of animals survived the Permian Extinction: Therapsids, which were mammal-like reptiles, and the more reptilian Archosaurs. In the early Triassic, it appeared that the Therapsids would dominate the new era. One genus, Lystrosaurus, has been called the Permian/Triassic “Noah,” as fossils of this animal predate the mass extinction but are also commonly found in early Triassic strata. However, by the mid-Triassic, most of the Therapsids had become extinct and the more reptilian Archosaurs were clearly dominant.

 

Archosaurs had two temporal openings in the skull and teeth that were more firmly set in the jaw than those of their Therapsid contemporaries. The terrestrial apex predators of the Triassic were the Rauisuchians, an extinct group of Archosaurs. In 2010, the fossilized skeleton of a newly discovered species, Prestosuchus chiniquensis, measured more than 20 feet (6 meters) in length. Unlike their close relatives the crocodilians, Rauisuchians had an upright stance but are differentiated from true dinosaurs by the way that the pelvis and femur were arranged. 


Another lineage of Archosaurs evolved into true dinosaurs by the mid-Triassic. One genus, Coelophysis, was bipedal. Although smaller than the Rauisuchians, they were probably faster as they had a more flexibly jointed hip. Coelophysis also picked up speed by having lightweight hollow bones. They had long sinuous necks, sharp teeth, clawed hands and a long bony tail. Coelophysis fossils found in large numbers in New Mexico indicate the animal hunted in packs. Some of the individuals found had remains of smaller members of the species inside the larger animals. Scientists are unclear as to whether this indicates internal gestation or possibly cannibalistic behavior.


By the late Triassic, a third group of Archosaurs had branched into the first pterosaurs. Sharovipteryx was a glider about the size of a modern crow with wing membranes attached to long hind legs. It was obviously bipedal with tiny, clawed front limbs that were probably used to grasp prey as it jumped and glided from tree to tree. Another flying reptile, Icarosaurus, was much smaller, only the size of a hummingbird, with wing membranes sprouting from modified ribs.


Earliest mammals


The first mammals evolved near the end of the Triassic Period from the nearly extinct Therapsids. Scientists have some difficulty in distinguishing where exactly the dividing line between Therapsids and early mammals should be drawn. Early mammals of the late Triassic and early Jurassic were very small, rarely more than a few inches in length. They were mainly herbivores or insectivores and therefore were not in direct competition with the Archosaurs or later dinosaurs. Many of them were probably at least partially arboreal and nocturnal as well. Most, such as the shrew-like Eozostrodon, were egg layers although they clearly had fur and suckled their young. They had three ear bones like modern mammals and a jaw with both mammalian and reptilian characteristics.

 

 

Originally published on Live Science.

 

 

Read more:


https://www.livescience.com/43295-triassic-period.html

 

 

See also Wildlife of Gondwana by Pat Rich. 

warming warning...

Antarctica has logged its hottest temperature on record at an Argentinian research station with a thermometer recording 18.3C, beating the previous record by 0.8C.

The reading, taken at Esperanza on the northern tip of the continent’s peninsular, beats Antarctica’s previous record of 17.5C, set in March 2015.

A tweet from Argentina’s meteorological agency on Friday revealed the record, which said it was a new record for the station since its records started in 1961.

 

Read more:

https://www.theguardian.com/world/2020/feb/07/antarctica-logs-hottest-te...

 

Meanwhile after recording the hottest february day in France:

 

For several days, the weather situation over the North Atlantic suggests a strong storm. According to Météo France, it will hit the British Isles, the Benelux and the northern third of France from Sunday.

While the possibility of a strong storm on the Atlantic coast has been agitating forecasters for several days, Météo France has published a press release specifying the calendar and the area of impact of the phenomenon. Described as a “strong winter storm”, Ciara will hit the northern third of the territory from Sunday, from Brittany to Hauts-de-France. It could include a fraction of the southernmost coast - Vendée, Charente-Maritime - because Météo France does not exclude an impact zone extended to "a large northern half" of France.

 

Read more:

https://www.sudouest.fr/2020/02/06/tempete-ciara-le-nord-de-la-france-en...

 

 

Read from top.

 

See what happens...