Tuesday, November 03, 2020

 LETTER

Protective effect of mandatory face masks in the public—relevant variables with likely impact on outcome were not considered

Günter Kampf

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Zhang et al. (1) conclude that wearing a face mask in public is the most effective means to prevent transmission. This conclusion is scientifically highly questionable. First, the number of epidemic-curve examples is small; an explanation of how they were chosen is lacking. Second, the evaluation is flawed by not taking into account where the majority of transmissions took place locally (e.g., in the public or by healthcare workers) and if adequate personal protective equipment was available for healthcare workers (2). Third, the authors assumed that face covering was the only effect and did not control for or analyze confounding variables. It is very unlikely that “social distancing” was the same in all selected epicenters. The World Health Organization recommends at least 1-m distance (3), whereas the Centers for Disease Control and Prevention recommends 6 feet (∼2 m). It is obvious that the distance itself is likely to have an impact on transmission. Would physical distancing be as effective as face masks when a distance >2 m would be the global standard? This important variable is not included for Italy, China, or the United States. Fourth, weather conditions or the population density may have an impact on its own (4). Coronavirus infections are usually seasonal infections resulting in a flattened curve toward the summer anyway (5). The different epidemic curves for the United States and New York shown by the authors may be also explained by differences of seasonality for New York alone and the entire United States including southern states where the epidemic arrived later. Fifth, mandatory face masks in the public may have the effect that fewer people leave their homes, resulting in a lower population density in the public followed by lower transmission rates. Face masks have been described to increase physical distancing in front of shops (6). However, Zhang et al. do not provide any observational data to demonstrate that population densities or distances were similar in each epicenter before and after mandatory face masks. Sixth, the authors claim that mandated face covering "significantly reduces the number of infections." This claim may be wrong because all databases count “cases” based on the nasopharyngeal detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA (7). A case is not necessarily a clinical infection because a substantial proportion of SARS-CoV-2 RNA carriers remain asymptomatic (8). Seventh, multiple interventions may have been implemented simultaneously, so that the differences are not necessarily attributable to just masks alone. Finally, data from Germany indicate that mandatory face masks in shops and public transport as a single measure did not accelerate the decline of new cases (9). The effect of any measure should have a suitable control including a stratification regarding the most relevant parameter such as age and health of population, epidemic stage, population density, season, weather, and compliance with the intervention measured by observation. The controls are lacking so that the authors’ assumptions are insufficiently justified, and therefore their analysis does not support their main claim.

Footnotes

  • Author contributions: G.K. wrote the paper.

  • Competing interest statement: G.K. has received personal fees from Dr. Schumacher GmbH, Germany, for presentation and consultation.

This open access article is distributed under Creative Commons Attribution License 4.0 (CC BY).

New study suggests diet and exercise are for the birds

New research shows that birds moderate food intake and activity level to manage their weight.


Katie Willis - 03 November 2020 UNIVERSITY OF ALBERTA 

To regulate their body mass, birds use a tried and true method—diet and exercise, according to new research by University of Alberta biologists. 

“The results are so simple that it's almost surprising,” said Kimberley Mathot, assistant professor in the Department of Biological Sciences in the Faculty of Science and Canada Research Chair in Integrative Ecology. “Anyone can tell you that if you want to lose weight, you should get moving and change how you eat. It turns out—birds do just that.”

Unlike mammals, which often become obese when given unlimited access to food, birds can maintain almost constant mass even when food is plentiful. And while understanding why body mass regulation is useful for birds has been a topic of research for many years, this is the first study to examine just how birds do it.

The research team conducted two experiments to examine how birds regulate their body mass. In the first, the scientists manipulated predation danger, which resulted in decreased body mass. “The results show that increased activity and decreased food intake—or dieting—contributed to the mass loss,” said Mathot.

In the second, birds were presented with two types of food—one high in quality and calories and one lower in quality. “Here, we found that birds maintained nearly constant body mass. This was also achieved by moving more and eating less when food was suddenly higher quality,” explained Mathot, who conducted this research in conjunction with Eva Kok, a PhD student who is co-supervised by Mathot and Theunis Piersma from the University of Groningen in the Netherlands.

Combined, these research results indicate that birds have mastered the simple and effective tools of managing diet and exercise to match their current environment. 

This work was done in collaboration with the NIOZ Royal Netherlands Institute for Sea Research, including Theunis Piersma, Piet van den Hout, and Anne Deking. This research was funded by a Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant, the Netherland Organisation for Scientific Research, and Waddenfonds.

The paper, “Red knots (Calidris canutus islandica) manage body mass with dieting and activity,” was published in the Journal of Experimental Biology(doi: 10.1242/jeb.231993).

#SPIRITANIMAL
Rare yellow 'albino' turtle that 'looks like melted burger cheese' is rescued from a village pond in India

Animal is believed to be a rare example of the specie called Indian flap shell
It is a bizarre yellow colour likely due to a genetic mutation causing albinism
Villagers s rescued the animal from a pond in a West Bengal, India


By JOE PINKSTONE FOR MAILONLINE

PUBLISHED: 3 November 2020 

A bizarre turtle that is bright yellow has been spotted in a village pond in West Bengal, India.

The rare animal is afflicted with a form of albinism which affects its colouration and has been compared online to melted cheese on a burger.

It belongs to a rare species called the Indian flap shell turtle.


A bizarre turtle that is bright yellow has been spotted in a village pond in West Bengal, India. The rare animal is afflicted with a form of albinism

Sneha Dharwadka posted images of the turtle on Twitter and suggested two potential explanations for its bizarre colouration. 

'It's an 
albino kind whose peculiar yellow colour is may be bcoz of either some genetic mutation or congenital disorder due to absence of tyrosine pigment,' he says. 

The Indian flap shell turtle, which is normally green, is typically found in South Asia and is between 9 to 14 inches long.

In August, a similar animal of the same species was discovered in Nepal.

At the time it was compared to a mythological incarnation of the Hindu deity Vishnu.

These two events make up just the fifth and sixth sightings of albinism in this species.



Sneha Dharwadka posted images of the turtle on Twitter and suggested two potential explanations for its bizarre colouration. 'It's an albino kind whose peculiar yellow colour is may be bcoz of either some genetic mutation or congenital disorder due to absence of tyrosine pigment,' he says


The Indian flap shell turtle, which is normally green, is typically found in South Asia and is between 9 to 14 inches long. In August, a similar animal of the same species was discovered in Nepal

pic.twitter.com/kNQ4F48lTI— Ordingandr (@Ordingandr96) November 1, 2020

Kamal Devkota, a reptile expert who documented the previous find, said the reptile had a deep spiritual significance.

'Not only golden animals but turtles overall have significant religious and cultural value in Nepal,' he said.

'It is believed that Lord Vishnu took the form of a turtle to save the universe from destruction in his incarnation.

'In Hindu mythology the upper shell of the turtle denotes the sky and lower shell denotes earth.'


Vi
 tushnu'srtle avatar, known as Kurma, is today worshipped in a number of temples in India.

The golden turtle owes its remarkable colour to chromatic leucism — a condition characterised by a loss of colour pigmentation.

Leucism usually results in white, pale or patchy skin, but in this case it lead to xanthophores — cells abundant with yellow pigments — becoming dominant.

God said: pic.twitter.com/3m20Iqk5Oe— WeaponTheory (@WeaponTheory) November 1, 2020

Kamal Devkota, a reptile expert who documented a similar previous find, said the reptile had a deep spiritual significance. 'Not only golden animals but turtles overall have significant religious and cultural value in Nepal,' he said

Uganda opposition presidential candidate Bobi Wine arrested, police rout protesters

By Elias Biryabarema

KAMPALA (Reuters) - Ugandan police used rubber bullets, live rounds and tear gas to break up a protest by supporters of opposition presidential candidate Bobi Wine after he was arrested on Tuesday following the filing of his nomination papers, aides and witnesses said.


FILE PHOTO: FILE PHOTO: Ugandan musician turned politician, Robert Kyagulanyi also known as Bobi Wine addresses a news conference at his home in Kasangati, Kampala, Uganda July 24, 2019. REUTERS/James Akena/File Photo

At least 15 people were injured in the disturbances at the home compound of Wine, 38, also a musician who has parlayed his relative youth and upbringing in a slum into a popular following against veteran President Yoweri Museveni.

Wine, whose real name is Robert Kyagulanyi, aims to end Museveni’s 35-year, increasingly authoritarian grip on power that has made him Africa’s third longest-ruling president.

Wine was detained near a venue where nominations were being filed with the electoral body and then driven in a police van to his compound, which was full of what aides said were thousands of supporters who had gathered in protest at his arrest.

Police moved in, firing tear gas and rubber bullets as well as some live rounds over the heads of the crowd, aides to Wine told Reuters by phone.


“The situation is very volatile...A lot of people have been injured,” an aide said from inside the compound. At least 15 people were injured from tear gas and rubber bullets, he said.

Police Spokesman Patrick Onyango said in a WhatsApp message there had been injuries and police would give details later. It was not immediately clear why Wine was arrested, as the election body had told him he met all the requirements for candidacy.

His youthful age, music and upbringing in a slum have earned him considerable popularity in the relatively young East African country of 42 million, unnerving Museveni’s ruling party and drawing periodic security crackdowns on Wine’s supporters.

“...Mr Museveni, since you have failed to control your greed and lust for power, our generation is determined to save you from yourself and stop your 35-year-old dictatorship,” Wine said in a speech before his arrest.



Don Wanyama, Museveni’s spokesman, did not respond to a Reuters call and texts requesting comment.

Wine has said that being “born hustling and born to hustling parents, raised in the ghettos”, meant he could understand the struggles of ordinary Ugandans.

Since he expressed his presidential ambitions, police and the military have repeatedly dispersed his rallies, and beaten and detained his supporters.

Museveni was cleared to run in the elections on Monday. Elections are scheduled for February next year.


Reporting by Elias Biryabarema; Editing by George Obulutsa and Mark Heinrich


Our Standards: The Thomson Reuters Trust Principles.







Neanderthals and humans were engaged in brutal guerrilla-style warfare across the globe for over 100,000 years, evidence shows

Neanderthals and Homo sapiens evolved from one ancestor 600,000 years ago 

Two species co-existed together until Neanderthal extinction
Dr Nicholas R. Longrich of the University of Bath explains it for The Conversation

By NICHOLAS R. LONGRICH FOR THE CONVERSATION

PUBLISHED: 3 November 2020

Neanderthals and Homo sapiens were closely related, sister species who evolved from the same ancestor and co-existed for millennia.

But scientists have tussled with trying to explain why Neanderthals went extinct around 40,000 years and humans lived on.

Several theories have been put forward to explain how this happened, including competition for the same resources, such as food and shelter; Neanderthals being unable to adjust to rapid climate change; and direct confrontation.


Now it is believed a combination of all of these things contributed to the Neanderthal extinction.

But the latest data reveals the two hominin species were fighting grisly guerrilla-style battles for 100,000 years.

Dr Nicholas R. Longrich, a senior lecturer in evolutionary biology and palaeontology at the University of Bath explains more in an article for The Conversation.

Scroll down for video

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This graph, created by study author Dr Longrich, shows the global battles which waged for millennia between Neanderthals and humans, both archaic (blue) and modern (red)


Far from peaceful, Neanderthals were likely skilled fighters and dangerous warriors, rivalled only by modern humans

Around 600,000 years ago, humanity split in two. One group stayed in Africa, evolving into us.

The other struck out overland, into Asia, then Europe, becoming Homo neanderthalensis – the Neanderthals. They weren’t our ancestors, but a sister species, evolving in parallel.

Neanderthals fascinate us because of what they tell us about ourselves – who we were, and who we might have become.

It’s tempting to see them in idyllic terms, living peacefully with nature and each other, like Adam and Eve in the Garden.

If so, maybe humanity’s ills – especially our territoriality, violence, wars – aren’t innate, but modern inventions.

Biology and paleontology paint a darker picture. Far from peaceful, Neanderthals were likely skilled fighters and dangerous warriors, rivalled only by modern humans.
Top predators

Predatory land mammals are territorial, especially pack-hunters. Like lions, wolves and Homo sapiens, Neanderthals were cooperative big-game hunters.

These predators, sitting atop the food chain, have few predators of their own, so overpopulation drives conflict over hunting grounds.

Neanderthals faced the same problem; if other species didn’t control their numbers, conflict would have.

This territoriality has deep roots in humans. Territorial conflicts are also intense in our closest relatives, chimpanzees.

Male chimps routinely gang up to attack and kill males from rival bands, a behaviour strikingly like human warfare.

This implies that cooperative aggression evolved in the common ancestor of chimps and ourselves, 7 million years ago.

If so, Neanderthals will have inherited these same tendencies towards cooperative aggression.




Neanderthalensis were skilled big game hunters, using spears to take down deer, ibex, elk, bison, even rhinos and mammoths. It defies belief to think they would have hesitated to use these weapons if their families and lands were threatened. Archaeology suggests such conflicts were commonplace

Homo sapiens WERE to blame for Neanderthal extinction

A supercomputer may have finally ended the debate over what caused the extinction of Neanderthals.

Mathematicians used the enormous processing power of the IBS supercomputer Aleph to simulate what happened throughout Eurasia around 40,000 years ago.

It revealed that the most likely explanation for Neanderthal extinction is that Homo sapiens, who migrated into Europe around the time of the extinction of Neanderthals, were better hunters and out-competed them for food.

Humans and Neanderthals are known to have overlapped, and even mated, but the superior brain power of Homo sapiens eventually wiped out their distant cousins.

Experts have long quarrelled over whether it was tumultuous climate patterns, competition for food with Homo sapiens or the interbreeding with this new species that ultimately led to the demise of Neanderthals.

All too human

Warfare is an intrinsic part of being human. War isn’t a modern invention, but an ancient, fundamental part of our humanity.

Historically, all peoples warred. Our oldest writings are filled with war stories.

Archaeology reveals ancient fortresses and battles, and sites of prehistoric massacres going back millennia.

To war is human – and Neanderthals were very like us. We’re remarkably similar in our skull and skeletal anatomy, and share 99.7% of our DNA.

Behaviourally, Neanderthals were astonishingly like us.

They made fire, buried their dead, fashioned jewellery from seashells and animal teeth, made artwork and stone shrines.

If Neanderthals shared so many of our creative instincts, they probably shared many of our destructive instincts, too.
Violent lives

The archaeological record confirms Neanderthal lives were anything but peaceful.

Neanderthalensis were skilled big game hunters, using spears to take down deer, ibex, elk, bison, even rhinos and mammoths.

It defies belief to think they would have hesitated to use these weapons if their families and lands were threatened.

Archaeology suggests such conflicts were commonplace.

Prehistoric warfare leaves telltale signs. A club to the head is an efficient way to kill – clubs are fast, powerful, precise weapons – so prehistoric Homo sapiens frequently show trauma to the skull. So too do Neanderthals.

Another sign of warfare is the parry fracture, a break to the lower arm caused by warding off blows. Neanderthals also show a lot of broken arms.

At least one Neanderthal, from Shanidar Cave in Iraq, was impaled by a spear to the chest.

Trauma was especially common in young Neanderthal males, as were deaths.

Some injuries could have been sustained in hunting, but the patterns match those predicted for a people engaged in intertribal warfare- small-scale but intense, prolonged conflict, wars dominated by guerrilla-style raids and ambushes, with rarer battles.


The Saint-Césaire Neanderthal skull (pictured) suffered a blow that split the skull around 36,000 years ago in France

A map showing the relative dates at which humans arrived in the different Continents, including Europe 45,000 years ago. Humans and Neanderthals co-existed for about 8,000 years before Neanderthals went extinct
The Neanderthal resistance

War leaves a subtler mark in the form of territorial boundaries. The best evidence that Neanderthals not only fought but excelled at war, is that they met us and weren’t immediately overrun.

Instead, for around 100,000 years, Neanderthals resisted modern human expansion.

Why else would we take so long to leave Africa? Not because the environment was hostile but because Neanderthals were already thriving in Europe and Asia.

It’s exceedingly unlikely that modern humans met the Neanderthals and decided to just live and let live.

If nothing else, population growth inevitably forces humans to acquire more land, to ensure sufficient territory to hunt and forage food for their children. But an aggressive military strategy is also good evolutionary strategy.

Instead, for thousands of years, we must have tested their fighters, and for thousands of years, we kept losing. In weapons, tactics, strategy, we were fairly evenly matched.

Neanderthals probably had tactical and strategic advantages.

They’d occupied the Middle East for millennia, doubtless gaining intimate knowledge of the terrain, the seasons, how to live off the native plants and animals.

In battle, their massive, muscular builds must have made them devastating fighters in close-quarters combat.

Their huge eyes likely gave Neanderthals superior low-light vision, letting them manoeuvre in the dark for ambushes and dawn raids.
Sapiens victorious

Finally, the stalemate broke, and the tide shifted. We don’t know why.

It’s possible the invention of superior ranged weapons – bows, spear-throwers, throwing clubs – let lightly-built Homo sapiens harass the stocky Neanderthals from a distance using hit-and-run tactics.

Or perhaps better hunting and gathering techniques let sapiens feed bigger tribes, creating numerical superiority in battle.

Even after primitive Homo sapiens broke out of Africa 200,000 years ago, it took over 150,000 years to conquer Neanderthal lands.

In Israel and Greece, archaic Homo sapiens took ground only to fall back against Neanderthal counteroffensives, before a final offensive by modern Homo sapiens, starting 125,000 years ago, eliminated them.

This wasn’t a blitzkrieg, as one would expect if Neanderthals were either pacifists or inferior warriors, but a long war of attrition.

Ultimately, we won. But this wasn’t because they were less inclined to fight. In the end, we likely just became better at war than they were.

The original article was published on The Conversation and can be read here.

A close relative of modern humans, Neanderthals went extinct 40,000 years ago


The Neanderthals were a close human ancestor that mysteriously died out around 40,000 years ago.

The species lived in Africa with early humans for millennia before moving across to Europe around 300,000 years ago.

They were later joined by humans, who entered Eurasia around 48,000 years ago.

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The Neanderthals were a cousin species of humans but not a direct ancestor - the two species split from a common ancestor - that perished around 50,000 years ago. Pictured is a Neanderthal museum exhibit

These were the original 'cavemen', historically thought to be dim-witted and brutish compared to modern humans.

In recent years though, and especially over the last decade, it has become increasingly apparent we've been selling Neanderthals short.

A growing body of evidence points to a more sophisticated and multi-talented kind of 'caveman' than anyone thought possible.

It now seems likely that Neanderthals had told, buried their dead, painted and even interbred with humans.

They used body art such as pigments and beads, and they were the very first artists, with Neanderthal cave art (and symbolism) in Spain apparently predating the earliest modern human art by some 20,000 years.

They are thought to have hunted on land and done some fishing. However, they went extinct around 40,000 years ago following the success of Homo sapiens in Europe.

War in the time of Neanderthals: how our species battled for supremacy for over 100,000 years