Permian-Triassic mass extinction by global warming


This July 2018 video says about itself:

252 million years ago 96% of all marine species and 70% of terrestrial vertebrate species vanished, this was the Permian extinction.

From the University of Washington in the USA:

Biggest mass extinction caused by global warming leaving ocean animals gasping for breath

December 6, 2018

Summary: By combining ocean models, animal metabolism and fossil records, researchers show that the Permian mass extinction in the oceans was caused by global warming that left animals unable to breathe. As temperatures rose and the metabolism of marine animals sped up, the warmer waters could not hold enough oxygen for their survival.

The largest extinction in Earth’s history marked the end of the Permian period, some 252 million years ago. Long before dinosaurs, our planet was populated with plants and animals that were mostly obliterated after a series of massive volcanic eruptions in Siberia.

Fossils in ancient seafloor rocks display a thriving and diverse marine ecosystem, then a swath of corpses. Some 96 percent of marine species were wiped out during the “Great Dying”, followed by millions of years when life had to multiply and diversify once more.

What has been debated until now is exactly what made the oceans inhospitable to life — the high acidity of the water, metal and sulfide poisoning, a complete lack of oxygen, or simply higher temperatures.

New research from the University of Washington and Stanford University combines models of ocean conditions and animal metabolism with published lab data and paleoceanographic records to show that the Permian mass extinction in the oceans was caused by global warming that left animals unable to breathe. As temperatures rose and the metabolism of marine animals sped up, the warmer waters could not hold enough oxygen for them to survive.

The study is published in the Dec. 7 issue of Science.

“This is the first time that we have made a mechanistic prediction about what caused the extinction that can be directly tested with the fossil record, which then allows us to make predictions about the causes of extinction in the future”, said first author Justin Penn, a UW doctoral student in oceanography.

Researchers ran a climate model with Earth’s configuration during the Permian, when the land masses were combined in the supercontinent of Pangaea. Before ongoing volcanic eruptions in Siberia created a greenhouse-gas planet, oceans had temperatures and oxygen levels similar to today’s. The researchers then raised greenhouse gases in the model to the level required to make tropical ocean temperatures at the surface some 10 degrees Celsius (20 degrees Fahrenheit) higher, matching conditions at that time.

The model reproduces the resulting dramatic changes in the oceans. Oceans lost about 80 percent of their oxygen. About half the oceans’ seafloor, mostly at deeper depths, became completely oxygen-free.

To analyze the effects on marine species, the researchers considered the varying oxygen and temperature sensitivities of 61 modern marine species — including crustaceans, fish, shellfish, corals and sharks — using published lab measurements. The tolerance of modern animals to high temperature and low oxygen is expected to be similar to Permian animals because they had evolved under similar environmental conditions. The researchers then combined the species’ traits with the paleoclimate simulations to predict the geography of the extinction.

“Very few marine organisms stayed in the same habitats they were living in — it was either flee or perish”, said second author Curtis Deutsch, a UW associate professor of oceanography.

The model shows the hardest hit were organisms most sensitive to oxygen found far from the tropics. Many species that lived in the tropics also went extinct in the model, but it predicts that high-latitude species, especially those with high oxygen demands, were nearly completely wiped out.

To test this prediction, co-authors Jonathan Payne and Erik Sperling at Stanford analyzed late-Permian fossil distributions from the Paleoceanography Database, a virtual archive of published fossil collections. The fossil record shows where species were before the extinction, and which were wiped out completely or restricted to a fraction of their former habitat.

The fossil record confirms that species far from the equator suffered most during the event.

“The signature of that kill mechanism, climate warming and oxygen loss, is this geographic pattern that’s predicted by the model and then discovered in the fossils,” Penn said. “The agreement between the two indicates this mechanism of climate warming and oxygen loss was a primary cause of the extinction.”

The study builds on previous work led by Deutsch showing that as oceans warm, marine animals’ metabolism speeds up, meaning they require more oxygen, while warmer water holds less. That earlier study shows how warmer oceans push animals away from the tropics.

The new study combines the changing ocean conditions with various animals’ metabolic needs at different temperatures. Results show that the most severe effects of oxygen deprivation are for species living near the poles.

“Since tropical organisms’ metabolisms were already adapted to fairly warm, lower-oxygen conditions, they could move away from the tropics and find the same conditions somewhere else,” Deutsch said. “But if an organism was adapted for a cold, oxygen-rich environment, then those conditions ceased to exist in the shallow oceans.”

The so-called “dead zones” that are completely devoid of oxygen were mostly below depths where species were living, and played a smaller role in the survival rates. “At the end of the day, it turned out that the size of the dead zones really doesn’t seem to be the key thing for the extinction,” Deutsch said. “We often think about anoxia, the complete lack of oxygen, as the condition you need to get widespread uninhabitability. But when you look at the tolerance for low oxygen, most organisms can be excluded from seawater at oxygen levels that aren’t anywhere close to anoxic.”

Warming leading to insufficient oxygen explains more than half of the marine diversity losses. The authors say that other changes, such as acidification or shifts in the productivity of photosynthetic organisms, likely acted as additional causes.

The situation in the late Permian — increasing greenhouse gases in the atmosphere that create warmer temperatures on Earth — is similar to today.

“Under a business-as-usual emissions scenarios, by 2100 warming in the upper ocean will have approached 20 percent of warming in the late Permian, and by the year 2300 it will reach between 35 and 50 percent,” Penn said. “This study highlights the potential for a mass extinction arising from a similar mechanism under anthropogenic climate change.”

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Gecko lizards can walk on water


This video says about itself:

Geckos can run across water

Geckos (Hemidactylus platyurus) have the ability to exceed the speed limits of conventional surface swimming, running across water at up to almost a meter a second using a unique mix of surface tension and slapping.

Credits: UC Berkeley/Roxanne Makasdjian/Stephen McNally/Pauline Jennings, Jasmine A. Nirody, Judy Jinn, Thomas Libby, Timothy J. Lee, Ardian Jusufi, David L. Hu, Robert J. Full.

Music: Horses to Water by Topher Mohr and Alex Elena courtesy of YouTube Audio Library

From the University of California – Berkeley in the USA:

Acrobatic geckos, highly maneuverable on land and in the air, can also race on water

Geckos combine surface tension with foot slapping to stay above water surface

December 6, 2018

Summary: Asian geckos were observed running over water at nearly a meter per second, as fast as on land. Lab experiments show how. They get support from surface tension but also slap the water rapidly with their feet. They also semi-plane over the surface and use their tail for stabilization and propulsion. They thus sit between insects, which use only surface tension, and larger animals, which run upright via foot slapping alone.

Geckos are renowned for their acrobatic feats on land and in the air, but a new discovery that they can also run on water puts them in the superhero category, says a University of California, Berkeley, biologist.

“They can run up a wall at a meter per second, they can glide, they can right themselves in midair with a twist of their tail and rapidly invert under a leaf running at full speed. And now they can run at a meter per second over water. Nothing else can do that; geckos are superheroes,” said Robert Full, a UC Berkeley professor of integrative biology.

Full is the senior author of a paper that will appear this week in the journal Current Biology describing four separate strategies that geckos use to skitter across the surface of water. First author Jasmine Nirody, a biophysicist at the University of Oxford and Rockefeller University, conducted much of the research with Judy Jinn, both as Ph.D. students at Berkeley.

According to Full, who discovered many of the unique maneuvers and strategies geckos employ, including how their toe hairs help them climb smooth vertical surfaces and hang from the ceiling, the findings could help improve the design of robots that run on water.

Nirody first became intrigued by geckos’ water-running behavior after co-author Ardian Jusufi, now a biophysicist at Max Planck Institute for Intelligent Systems and another former UC Berkeley Ph.D. student, noticed that geckos in the forests of southeast Asia could skitter across puddles to escape predators.

In fact, they are able to run at nearly a meter, or three feet, per second over water and easily transition to speeding across solid ground or climbing up a vertical surface. Geckos sprinting on the water’s surface exceed the absolute swimming speeds of many larger, aquatic specialists including ducks, minks, muskrats, marine iguanas and juvenile alligators, and are faster in relative speed than any recorded surface swimmer, other than whirligig beetles.

How, she wondered, do they do that?

Smaller animals like insects — spiders, beetles and water striders, for example — are light enough to be kept afloat by surface tension, which allows them to easily glide across the surface. Larger animals, such as swans during takeoff or the basilisk lizard, and even dolphins rising up on their tails, rapidly slap and stroke the water to keep above the waves.

“Bigger animals can’t use surface tension, so they end up pushing and slapping the surface, which produces a force if you do it hard enough,” Full said.

But the gecko is of intermediate size: at about 6 grams (one-fifth of an ounce, or the weight of a sheet of paper), they are too large to float above the surface, but too light to keep their bodies above water by slapping forces only.

“The gecko’s size places them in an intermediate regime, a middle ground,” Nirody said. “They can’t generate enough force to run along the surface without sinking, so the fact they can race across water is really surprising.”

In experiments with flat-tailed house geckos (Hemidactylus platyurus), common in south and southeast Asia, she discovered that they actually use at least two and perhaps four distinct strategies to run atop the water surface.

Surface tension is essential, she found, because when she applied a surfactant or soap to eliminate surface tension, the geckos were much less efficient: their speed dropped by half.

Even without surface tension, however, they can move using slapping, paddling movements with their four legs like larger animals. Leg slapping created air pockets that helped keep their bodies from being completely submerged, allowing them to trot across the water in much the same way they run on land.

But they also seem to use their smooth, water-repellent skin to plane across the surface, similar to hydroplaning but referred to as semi-planing, a technique used by muskrats.

Finally, they also use their tail to swish the water like an alligator, providing propulsion as well as lift and stabilization.

“All are important to some extent, and geckos are unique in combining all these,” Full said.

“Even knowing the extensive list of locomotive capabilities that geckos have in their arsenal, we were still very surprised at the speed at which they could dart across the water’s surface,” Nirody said. “The way that they combine several modalities to perform this feat is really remarkable.”

In the lab, she and her colleagues built a long water tank, placed the geckos on a plank and startled them by touching their tails. Using high-speed video, they were able to closely study the geckos’ techniques and estimate the forces involved.

This research was funded by the National Science Foundation and the Swiss National Science Foundation. Other co-authors of the paper are Thomas Libby and Timothy Lee of UC Berkeley and David Hu from Georgia Tech.

Dutch Islamophobic far-right terrorist convicted


Far-right terrorist Vincent T. in the dock

Translated from Dutch NOS TV today:

Three years cell for Vincent T. for his plans to murder Muslims and left-wing people

The Gelderland [ex soldier and ex election candidate for a xenophobic party] terrorist suspect Vincent T. has been sentenced to three years in prison. He was found guilty of preparing murder with terrorist intent, reports Omroep Gelderland regional broadcasting organisation. Against him three years and four months had been demanded by the public prosecutor.

The 44-year-old man from Doornenburg was arrested in the spring and was since then in the extra security prison in Vught. Two gas guns and 1800 bullets were found in the house where he lived with his parents. He had tried to buy a gun that was suitable for the bullets.

Offing left-wing leaders

In chat conversations he indicated that he wanted to murder Muslims and also, eg, … [Surinamese Dutch anti-racist member of Amsterdam local council] Sylvana Simons. He would like to “off prominent left-wingers“.

He also had a leading role in the Facebook group ATB Special Forces, with which he wanted to set up an anti-Muslim militia. In addition, he searched on the Internet for instructions to make a bomb and to hire a contract murderer.

Macaques

According to the court, the accused has passed the phase of “keyboard terrorism”. He had told a member of the Facebook group that he wanted to hang or shoot dead anti-fascists and talked about “shooting macaques”.

Macaques are some species of monkeys. Racists, like in Belgium and in the right wing of the United States Republican party, use the word as an insult against Africans and other non-white people.

“If people are threatened precisely because of their convictions and must fear violence specifically directed against them, then the suspect will also cause serious fears to the population or parts of them”, is stated in the verdict.

Psychological and psychiatric research shows that T. has a poorly developed conscience and a personality disorder. He tends to pretend to be more important than he is. “He is in denial about his structural social failure and he covers it up with accusations towards foreigners.”

Blue-fronted Amazon parrot genome studied


This 2015 video shows a blue-fronted parrot, Amazona aestiva, eating guaritá, Astronium graveolens, flowers in Mato Grosso do Sul in Brazil.

From Carnegie Mellon University in the USA:

Parrot genome analysis reveals insights into longevity, cognition

Genome of blue-fronted Amazon parrot compared with 30 other long-lived birds

December 6, 2018

Parrots are famously talkative, and a blue-fronted Amazon parrot named Moises — or at least its genome — is telling scientists volumes about the longevity and highly developed cognitive abilities that give parrots so much in common with humans. Perhaps someday, it will also provide clues about how parrots learn to vocalize so well.

Morgan Wirthlin, a BrainHub post-doctoral fellow in Carnegie Mellon University’s Computational Biology Department and first author of a report to appear in the Dec. 17 issue of the journal Current Biology, said she and her colleagues sequenced the genome of the blue-fronted Amazon and used it to perform the first comparative study of parrot genomes.

By comparing the blue-fronted Amazon with 30 other long- and short-lived birds — including four additional parrot species — she and colleagues at Oregon Health and Science University (OHSU), the Federal University of Rio de Janeiro and other entities identified a suite of genes previously not known to play a role in longevity that deserve further study. They also identified genes associated with longevity in fruit flies and worms.

“In many cases, this is the first time we’ve connected those genes to longevity in vertebrates,” she said.

Wirthlin, who began the study while a Ph.D. student in behavioral neuroscience at OHSU, said parrots are known to live up to 90 years in captivity — a lifespan that would be equivalent to hundreds of years for humans. The genes associated with longevity include telomerase, responsible for DNA repair of telomeres (the ends of chromosomes), which are known to shorten with age. Changes in these DNA repair genes can potentially turn cells malignant. The researchers have found evidence that changes in the DNA repair genes of long-lived birds appear to be balanced with changes in genes that control cell proliferation and cancer.

The researchers also discovered changes in gene-regulating regions of the genome — which seem to be parrot-specific — that were situated near genes associated with neural development. Those same genes are also linked with cognitive abilities in humans, suggesting that both humans and parrots evolved similar methods for developing higher cognitive abilities.

“Unfortunately, we didn’t find as many speech-related changes as I had hoped,” said Wirthlin, whose research is focused on the evolution of vocal behaviors, including speech. Animals that learn songs or speech are relatively rare — parrots, hummingbirds, songbirds, whales, dolphins, seals and bats — which makes them particularly interesting to scientists, such as Wirthlin, who hope to gain a better understanding of how humans evolved this capacity.

“If you’re just analyzing genes, you hit the end of the road pretty quickly,” she said. That’s because learned speech behaviors are thought be more of a function of gene regulation than of changes in genes themselves. Doing comparative studies of these “non-coding” regulatory regions, she added, is difficult, but she and Andreas Pfenning, assistant professor of computational biology, are working on the computational and experimental techniques that may someday reveal more of their secrets.

This work was supported through the Brazilian Avian Genome Consortium and by the National Institutes of Health/National Institute on Deafness and Other Communication Disorders.

French police brutality against high school students


This French video from daily Le Monde says about itself (translated):

Shocking images of high school students arrested by police in Mantes-la-Jolie

Images of arrests of dozens of high school students in Mantes-la-Jolie were broadcast on social networks on December 6th [2018].

They show rows of dozens of students, kneeling with their hands on their heads, under the supervision of helmeted policemen armed with batons and shields.

A total of 153 people were arrested in Mantes-la-Jolie (Yvelines), Thursday, December 6, according to the prosecutor of the Republic of Versailles, Vincent Lesclous ….

The arrested people, mostly students [of the lycée Saint-Exupéry], are suspected of “participation in an armed crowd”, said the city commissioner Arnaud Verhille, claiming to want to “interrupt an uncontrolled process.” In the Yvelines, a total of 189 young people, aged 12 to 20 years, were placed in custody, according to the prosecutor of Versailles.

Images of the arrests were broadcast on social networks. They show rows of dozens of students on their knees, their hands crossed behind their heads, under the supervision of helmeted policemen armed with batons and shields. Some are lined up, forehead against a wall.

It looks like the French Macron government is moving closer to the methods of fascist dictator Pétain and his ideologist Maurras, both praised by Macron.

Translated from (‘centrist’ ‘Christian Democrat’) Belgian daily De Standaard today:

French people are dismayed about the police action against protesting students. 153 students from a secondary school in Mantes-la-Jolie, an hour’s drive from Paris, were ordered to kneel down by the police and keep their hands above their heads or behind their backs.

The police detained the students on Thursday as a reaction to their protest against educational reforms in France. According to the French Minister of the Interior, there were violent conflicts with the police, as a result of which a group of 122 young people were taken into custody. According to the minister, dozens of young people had sticks, baseball bats and tear gas. …

Pupils in about 280 secondary schools in France protested Thursday again in imitation of the ‘yellow vests’. A major problem for the pupils is Parcoursup, a system that determines whether students can continue studying at universities. The software is not working properly yet, which makes for bad blood in the youth.

While filming the students, the filmmaker says ‘this is a good class’.

The actions of the police officers are condemned on social media. Benoît Hamon, former Minister of Education,

Hamon was then a left-wing critic of Prime Minister Valls, of the right wing of the Socialist Party. Hamon then beat Valls in the vote to become Socialist candidate in the 2017 presidential election. Later, he left the Socialist Party in disgust about its right-wing course and formed his own party.

wrote “This is not the Republic. French youth was humiliated.” The French politician Clémentine Autain finds it ‘frightening’ and ‘unacceptable from a human and democratic point of view’.

Brazilian tree frogs parenting, new study


This June 2015 video says about itself:

7 Tiny Frogs Found on 7 Brazilian Mountains

Researchers in Brazil discovered seven never-before-seen species of Brachycephalus frog on seven different mountains in the Atlantic forest.

From PLOS:

Not too big, not too small: Tree frogs choose pools that are just right

Frogs breeding in pools of water on leaves face trade-off between drying out and repelling predators

December 5, 2018

Frogs that raise their young in tiny pools of water that collect on plant leaves must make a delicate trade-off between the risk of drying out and the risk of being eaten, according to a study publishing December 5 in the open-access journal PLOS ONE by Mirco Solé from the Universidade Estadual de Santa Cruz in Bahia, Brazil and colleagues.

The temporary pools of water trapped by the leaf rosette of some plants in the Bromeliaceae family are used by a variety of creatures as a source of prey, water and shelter — one example is the Broad-snout casque-headed Tree Frog (Aparasphenodon arapapa) which uses the water ‘tanks’ of bromeliad plants as a place to mate and rear its tadpoles. To understand how the frogs choose the right spot, the researchers measured the characteristics, including size, water level, and leaf debris, of the central tanks of 239 bromeliads in Reserve Boa União in Bahia, Brazil.

They compared bromeliads that were occupied by a tree frog with those that were empty and found that male frogs generally prefer bromeliads with larger tanks, a higher volume of water, and less leaf litter — qualities which make the tanks less likely to dry up and easier to access. However, the very largest and fullest bromeliad tanks were frog-less, suggesting that a trade-off exists when choosing the best place to breed. Males have a specially shaped bony head that they use to form a tight seal with the opening of the bromeliad tank, which is thought to protect them from predators. Forming a tight seal may be tricky in very large bromeliads, making them a poor choice as a shelter.

The authors conclude that the trade-offs animals face when selecting a site to breed should be taken into consideration in conservation strategies.

Solé adds: “Aparasphenodon arapapa, a tropical frog from the Brazilian Atlantic Forest places its eggs into bromeliads, but instead of simply choosing the largest bromeliad tank with the most water, complex trade-offs between selection pressures and balancing water requirements are involved in the bromeliad choice.”