Permian-Triassic extinction survivor discovered in Antarctica

An anomodont skull of Suminia

From BigNews Network:

Antarctica may have served as climatic refuge in Earth’s greatest extinction event

ANI Thursday 3rd December, 2009

Washington: A new fossil species suggests that some land animals may have survived Earth’s greatest extinction event, about 252 million years ago, by taking refuge in cooler climates in Antarctica.

Jorg Frobisch and Kenneth D. Angielczyk of The Field Museum together with Christian A. Sidor from the University of Washington have identified a distant relative of mammals, Kombuisia antarctica, that apparently survived the mass extinction at the end of the Permian Period by living in Antarctica.

The new species belongs to a larger group of extinct mammal relatives, called anomodonts, which were widespread and represented the dominant plant eaters of their time.

“Members of the group burrowed in the ground, walked the surface and lived in trees,” said Frobisch, the lead author of the study.

Kombuisia antarctica was not a direct ancestor of living mammals, but it was among the few lineages of animals that survived at a time when a majority of life forms perished.

When it served as refuge, Antarctica was located some distance north of its present location, was warmer and wasn’t covered with permanent glaciers, according to the researchers.

The refuge of Kombuisia in Antarctica probably wasn’t the result of a seasonal migration but rather a longer-term change that saw the animal’s habitat shift southward.

Fossil evidence suggests that small and medium sized animals were more successful at surviving the mass extinction than larger animals.

They may have engaged in “sleep-or-hide” behaviors like hibernation, torpor and burrowing to survive in a difficult environment.

Earlier work by Fröbisch predicted that animals like Kombuisia antarctica should have existed at this time, based on fossils found in South Africa later in the Triassic Period that were relatives of the animals that lived in Antarctica.

“The new discovery fills a gap in the fossil record and contributes to a better understanding of vertebrate survival during the end-Permian mass extinction from a geographic as well as an ecological point of view,” Frobisch said.

The team found the fossils of the new species among specimens collected more than three decades ago from Antarctica that are part of a collection at the American Museum of Natural History.

See also here. And here.

Relationships & Monophyly of Therocephalian Therapsids: here.

An investigation into the cladistic relationships and monophyly of therocephalian therapsids (Amniota: Synapsida): here.

Dr Chen and his team are studying the much delayed recovery of marine species after the ‘Great Dying’, which occured 251 million years ago, by examining fossils around the world, particularly in his native South China, which, during the Triassic, enjoyed a temperate climate and was the site of a major re-flourishing of microfloras, then invertebrates and vertebrates following an order from low to high levels comparable to modern ecosystems: here.

The Permian extinction event was the biggest shake-up of life that Earth has ever seen: in the “Great Dying” that took place 250 million years ago, more than 90 percent of marine species were killed and about 70 percent of land animals vanished. The cause of this catastrophe has been debated for years, but new research suggests that volcanic eruptions triggered massive coal fires that pumped pollution into the air, eventually poisoning the planet: here.

The end-Permian crisis, by far the most dramatic biological crisis to affect life on Earth, was triggered by a number of physical environmental shocks – global warming, acid rain, ocean acidification and ocean anoxia. These were enough to kill off 90 per cent of living things on land and in the sea: here.

Tetraceratops insignis is not a close and nearly unknown relative with 4 horns of the well-known dinosaur Triceratops, but a very ancient mammal-like reptile or sphenacodontid (intermediate between therapsids and pelycosaurs). This classification is still uncertain and controversial among palaeontologists and, consequently, not definitive. In any case, Tetraceratops is considered an early therapsid, maybe the first one and still not completely evolved as such.

Scientists have uncovered a lot about the Earth’s greatest extinction event that took place 250 million years ago when rapid climate change wiped out nearly all marine species and a majority of those on land. Now, they have discovered a new culprit likely involved in the annihilation: an influx of mercury into the eco-system: here.

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Theo van Doesburg, Nelly van Doesburg, dadaism, De Stijl

This is a video about paintings by Theo van Doesburg.

He was born Christian Emil Marie Küpper, in Utrecht, in 1883. He died in Davos, in 1931.

At the moment, there is a big exhibition, called Van Doesburg and the international avant-garde. Constructing a new world. Next year, the exhibition wil move to Tate Modern in London.

Both Theo van Doesburg, and his third wife Nelly van Moorsel, played major roles in the artistic movements of Dadaism and De Stijl. Both movements arose in 1916-1917, as reactions against World War I.

Both were avant-garde movements with some of the paradoxes which may be involved in this.

Some of the people in De Stijl had fled from the war, from belligerent countries like Hungary, to the neutral Netherlands. De Stijl was internationalist, against the nationalist ideologies which had contributed to the war.

Theo van Doesburg personally had been a soldier in the Dutch army from 1914 to 1916. Though the Dutch army then did not participate in the bloodbath, van Doesburg whose unit guarded the Belgian border, had heard from refugees about the horrors that Belgium was going through.

In Van Doesburg, like in many other people then, this lead to the view that drastic change was needed in a society which had led to this horrible war. Before the war, Van Doesburg’s interest in politics had been limited to membership in the Vrijzinnig-Democratische Bond. That was a moderate liberal party, just slightly left of center (though it was also pacifist; contrary to some people today calling themselves liberal leftists).

Like Van Doesburg was not a life-long political revolutionary, he also was no avant-garde artist from his cradle to his grave, no artistic revolutionary for the sake of it. Before the war, he did, eg, a fairly conventional landscape painting of the dunes of Meijendel near The Hague (included in the exhibition). In 1912, he was critical of the (politically and artistically ambiguous) futurist movement.

Van Doesburg during the war and later wanted to do more to change society.

In this, he claimed a central role for art, more precisely, his new tendency in art moving towards abstraction. Didn’t he over-estimate the role of art in social change, as other artists (and people in other professions) may over-estimate the influence of their own roles?

It may not all be artistic self-overestimation, if we look at the views on this issue of Trotsky and Stalin: both politicians, not artists. Different from each other. But both saw the role of the arts as important. Trotsky wrote much about art, including a joint manifesto with French surrealist artist André Breton. Stalin said that the work of writers was more important than producing tanks.

Theo van Doesburg had links to Russian avant-garde artists, like the constructivists.

This is a video from the USA about De Stijl.

Piet Mondriaan originally was a De Stijl colleague of Van Doesburg. Eventually, both had a conflict, however. In Mondriaan’s theory, there should just be horizontal and vertical lines in paintings etc., no diagonal lines. While Van Doesburg eventually brought back diagonal lines in his work. Mondriaan’s views on horizontal and vertical lines were influenced by Theosophy, and ideas there about “active” males vs. “passive” females. Ideas that were problematic for the active role of Nelly van Doesburg and other women in De Stijl and dadaism.

This video says about itself:

The Dada movement was a protest against the barbarism of World War I, the bourgeois interests that Dada adherents believed inspired the war, and what they believed was an oppressive intellectual rigidity in both art and everyday society. Dada was an international movement, and it is difficult to classify artists as being from any one particular country, as they were constantly moving from one place to another.

On 15 November 2009, there was an interview with art historian, and niece and biographer of Nelly van Doesburg, Ms Wies van Moorsel.

Nelly van Moorsel came from a rather conventional Roman Catholic shopowner’s family. Unusually for such a background, she went to music school to learn to play the piano, on the advice of the architect Berlage, their next door neighbour. However, the music school was conventional in its own way. Nelly did not learn anything there about music written after the nineteenth century Romantic composers. In 1920, she first met Theo van Doesburg in The Hague. He asked her about modern composers like Erik Satie. In her reply she managed to avoid to show that her education had taught her nothing about modern composers. Soon, they fell in love; which lead to a break with her family.

When Wies van Moorsel in the 1960s had the first long meeting with her aunt, Nelly van Doesburg asked her about the latest trends in visual arts. Like in her aunt’s 1910s music school, Ms van Moorsel’s art history education excluded new avant-garde tendencies, and she was unable to reply seriously.

Nelly van Doesburg soon learnt about 1920s avant-garde music. In 1923, during a series of dadaist performances in the Netherlands, she started playing Chopin on the piano; what conventional audiences expected from music. Then, suddenly, she disoriented the audience by changing to very recent piano compositions.

After Theo van Doesburg’s death, Nelly organized many exhibitions of the works of her late husband and other artists. Late in her life, she was still very interested in social and political issues, like opposition to the war in Algeria. Like the students’ and workers’ movement in 1968 in Paris where she lived. Like anti pollution movements. She told Wies van Moorsel that Theo, if he would have been still alive, would have been an activist rather than an artist. A view, different from the central role for art which Theo himself had claimed decades earlier.

Barney Bubbles who designed many punk and New Wave record sleeves in the 1970s-1980s, was much influenced by Theo van Doesburg.

About the Van Doesburg exhibition in London:

The visitor’s guide does not explain the socio-historical context of war and revolutions which gave artists such utopian desire to create a better world. This is a serious omission which will particularly affect younger viewers, since history is now taught so cursorily in schools.

A new book on the history of anti-war movements in Britain illuminates the stories of those who refused to fight in the First World War. Chris Bambery looks at their struggle: here.

Arts and society: here.

The Automatiste Revolution: Montreal 1941-1960: The Varley Art Gallery, Unionville, Ontario, until Feb. 28, 2010; The Albright-Knox Art Gallery, Buffalo, New York, March 19 to May 30, 2010; review here.

Jan van der Marck, former chief curator at the Detroit Institute of Arts, dies. On his views about art and society, see here.