Barn swallows, parasites and evolution


This September 2016 video is about a barn swallow nesting colony in a hide in the Oostvaardersplassen national park in the Netherlands.

From the University of Colorado at Boulder in the USA:

Resident parasites influence appearance, evolution of barn swallows

June 24, 2020

Summary: Researchers think that local parasites are influencing why barn swallows in Europe, the Middle East and Colorado are choosing their mates differently. Their new research finds that these parasites could be playing an important role in changing the traits displayed to attract mates early in the process of the creation of new species.

Barn swallows live almost everywhere on the planet, recognizable by their forked tail and agility in the air. Yet while they share these characteristics, these little birds often look slightly different in each place they live — with some so distinct they’re splitting off to become new species.

Researchers at CU Boulder think that local parasites are influencing why barn swallows in Europe, the Middle East and Colorado are choosing their mates differently. Their new research, published in Evolution, finds that these parasites could be playing an important role in changing the traits displayed to attract mates early in the process of the creation of new species.

“It’s possible we haven’t appreciated just how important parasites might be in shaping the evolution of their hosts,” said lead author Amanda Hund, who conducted the research as a doctoral candidate in the Ecology and Evolutionary Biology Department.

Every organism, including humans, has co-evolved with a unique community of parasites, that by definition live at the expense of their host. While they are not beneficial to us like many other microbes are, parasites have shaped our own immune system, pheromones and even our mate selection, previous research has shown.

Hund set out to characterize as many parasite communities as she could in barn swallows, to find out if they could be influencing their mate selection, and therefore the male birds’ physical traits and the creation of new species.

Hund and her colleagues studied barn swallows at sites in Colorado, the Czech Republic and Israel over four years. They measured the number and types of parasites on them, in their nests and in their blood and tracked who they chose to mate with in a given breeding season, their sexual signals — breast color, throat color and tail shape — and their health and the survival rate of their offspring.

In all but one population in the study, the most “attractive” males had fewer parasites. Somehow the male birds’ breast color, throat color and tail shape allowed females to make informed choices about their health and the likelihood of reproductive success with that partner.

Many birds also had multiple parasites with connections to the same physical trait. For example, in Colorado, males with darker breast color are less likely to have mites, but more likely to have malaria. Nest mites are detrimental to the nestlings’ survival — whereas malaria only impacts the male bird.

“Males are investing in traits to attract females, and it looks like that comes at a cost — where they are more attractive, but also more susceptible to malaria,” said Hund, now a postdoctoral fellow at the University of Minnesota. “It is a tradeoff.”

Evolution in action

Researchers who study the origin of biodiversity, or why the Earth has so many different species, often examine which traits animals are choosing in their partners. But the real question is: Why are they choosing those specific combinations of traits?

To answer that question requires a very detailed type of scientific research, looking at the full reproductive cycle, health and survival rate of a population, in order to create a rich data set that unpacks how evolution is working between closely related populations.

“Most people are really good at characterizing the pattern. But Amanda’s work is very special in terms of trying to unpack the process,” said Rebecca Safran, associate professor in the Department of Ecology and Evolutionary Biology and co-author on the study.

Many factors affect the divergent evolution of species. But as opposed to something like the weather, parasites are evolving as rapidly as their host species — leading to a co-evolutionary relationship. While this has been studied in other animals, it has only previously been studied in one barn swallow population in Europe.

Barn swallows make a great study specimen: they’re ubiquitous and charismatic.

“These birds have evolved alongside humans for thousands of years. Every culture that we’ve visited seems to have its own unique story or relationship with this bird,” said Safran.

But because they nest almost exclusively in human-made structures — barns, bridges, culverts and the like — barn swallows often live on private land. It turns out that winning the trust of landowners is as much a part of the work as catching the birds.

“Public relations is a very large part of barn swallow research,” said Hund.

Safran has been working with dozens of collaborators all over the world for over a decade. Hund built off these connections to do this research in Europe and the Middle East, facing unique circumstances and language barriers along the way.

In Israel Hund lived on a Kibbutz, a collective community, in order to complete her research over several months. In the Czech Republic, Hund used award-winning skills from her childhood and rode horses at an equestrian center to build trust and gain access to an important nesting site.

And here in Colorado, there were landowners who were unsure or suspicious of the project at the start of the breeding season. “But by the end, they were having us over for dinner,” said Hund.

The work doesn’t stop here. The researchers are already trying to answer the next big question: why are local parasites and certain sexual traits linked?

“And once you really figure that out, you can export that knowledge and our study methods to other populations and actually watch mate selection decisions and the associated reproductive consequences unfold,” said Safran. “It’s like watching evolution in action.”

COVID-19 disaster in the Americas


This 25 June 2020 video from the USA says about itself:

Trump breaks all orders to go golfing. A Trump spokesman then responded he’s ‘not a civilian’ and he can be as irresponsible as he wants. John Iadarola and Adrienne Lawrence break it down on The Damage Report.

“The White House said Wednesday that President Donald Trump will not change his plan to travel to New Jersey this weekend despite a new order by the governor requiring visitors who have been in states with high numbers of coronavirus cases to quarantine for 14 days.

“The president of the United States is not a civilian,” said White House spokesman Judd Deere, when asked about Trump’s compliance with the quarantine order given his travel Tuesday to Arizona, which has seen a rise in the rate of its Covid-19 cases.

Coronavirus spreads across US, surging to the highest single-day count of new cases. By Kevin Reed, 26 June 2020. The number of newly confirmed coronavirus cases across the US set a one-day record on Thursday as the pandemic spread and surged in states in the South and West.

Production stoppage continues Friday at Fiat Chrysler Jefferson North auto plant in Detroit over COVID-19. By Shannon Jones, 26 June 2020. Workers arriving Friday morning have continued a stoppage that began Thursday after reports of three cases of COVID-19 among workers in the factory.

As COVID-19 spreads in Minnesota, Wisconsin warehouses. Amazon worker’s job in limbo after seeking to take time off for injury. By Nick Barrickman, 25 June 2020.

This 26 June 2020 video from the USA says about itself:

‘I don’t wear a mask for the same reason I don’t wear underwear: Things gotta breathe.’ — Anti-maskers in Florida are warning of satanism, pedophilia, and even death if public health policies are enforced.

COVID-19 ravages southeastern United States. By Cordell Gascoigne, 26 June 2020. Nine states are facing rising infection and death rates due to the criminal negligence of governments from the Texas state line on the west to the Atlantic Ocean.

Detroit nurses’ lawsuit exposes horrific conditions at Sinai-Grace Hospital as COVID-19 deaths spiked. By Kevin Reed, 25 June 2020.

Nurses and support staff at HCA Healthcare set to strike California hospital over cuts and PPE shortages. By Benjamin Mateus, 26 June 2020. One thousand nurses and support staff at HCA Healthcare are set to strike over concessions the hospital chain is demanding from frontline health care workers as the coronavirus pandemic continues to spread across the US.

As COVID-19 cases continue to climb throughout US. Hundreds of thousands of Illinois workers forced to risk health for profits under “Phase 4” of economic reopening. By Jessica Goldstein, 25 June 2020.

New York Times column: Pandemic shows need to curtail “unnecessary” and “wasteful” doctor’s visits. By Kate Randall, 25 June 2020.

As COVID-19 cases triple in a month, Latin American elites press ahead with back-to-work campaign. 26 June 2020. The ruling classes in the most unequal region of the world have based their response to the pandemic and the economic crisis it spurred on protecting their wealth and privileges at all costs: here.

Brazilian government hides scale of COVID-19 pandemic to promote criminal reopening. By Tomas Castanheira, 25 June 2020.

Prehistoric saber-tooth marsupial Thylacosmilus, new research


This December 2017 video says about itself:

Thylacosmilus || A Jaguar sized Saber-tooth Marsupial relative from South America

Thylacosmilus is an extinct genus of saber-toothed metatherian that inhabited South America from the Late Miocene to Pliocene epochs.

Though Thylacosmilus is one of several predatory mammal genera typically called “saber-toothed cats”, it was not a felid placentalian, but a sparassodont, a group closely related to marsupials, and only superficially resembled other saber-toothed mammals due to convergent evolution.

Remains of this animal have been found primarily in Catamarca, Entre Ríos, and La Pampa Provinces in northern Argentina.

Thylacosmilus was described and named by Elmer S. Riggs in 1933. He named two species, T. atrox and T. lentis.

Thylacosmilus had large, saber-like canines. The roots of these canines grew throughout the animal’s life, growing in an arc up the maxilla and above the orbits. Its cervical vertebrae were very strong and to some extent resembled the vertebrae of Machairodontinae.

Body mass estimates of Thylacosmilus suggest this animal weighed between 80 to 120 kilograms (180 to 260 lb), and one estimate suggesting up to 150 kg (330 lb), about the same size as a modern jaguar. This would make it one of the largest known carnivorous metatherians.

Recent comparative biomechanical analysis have estimated the bite force of T. atrox starting at maximum gape at 38 newtons (8.5 lbf), much weaker than that of a leopard, suggesting its jaw muscles had an insignificant role in the dispatch of prey.

Its skull was similar to that of Smilodon in that it was much better adapted to withstand loads applied by the neck musculature.

Based on studies of its habitat, Thylacosmilus is believed to have hunted in savanna-like or sparsely forested areas, avoiding the more open plains where it would have faced competition with the more successful and aggressive Phorusrhacids it shared its environment with.

Although older references have often stated that Thylacosmilus became extinct due to competition with the “more competitive” saber-toothed cat Smilodon during the Great American Interchange, newer studies have shown this is not the case.

Thylacosmilus died out during the Pliocene (3.6–2.58 mya) whereas saber-toothed cats are not known from South America until the Middle Pleistocene (781-126,000 years ago).

As a result, the last appearance of Thylacosmilus is separated from the first appearance of Smilodon by over one and a half million years.

From the University of Bristol in England:

Bizarre saber-tooth predator from South America was no saber-tooth cat

June 26, 2020

A new study led by researchers from the University of Bristol has shown that not all saber-tooths were fearsome predators.

Saber-tooth cats, such as the North American species Smilodon fatalis, are among the most iconic fossil animals with a reputation for being fierce predators. However, saber-tooths came in all shapes and sizes and nearly a hundred different saber-tooths are known to science so far.

Thylacosmilus atrox (which means ‘terrible pouched knife’) is a well-known animal that lived around five million years ago in Argentina.

A jaguar-sized marsupial, it is popularly known as the ‘marsupial saber-tooth’, compared with the sabertoothed cats elsewhere in the world, and it is often presented as a classic case of convergent evolution — where animals appear similar in form despite having very different evolutionary relationships (such as marsupial flying possums and placental flying squirrels — both, of course, being gliders rather than true fliers).

Thylacosmilus had huge, ever-growing canines, leading people to speculate that it was an even more vicious predator than the placental carnivores it superficially resembled such as Smilodon.

But was it really a fierce predator like the extinct placental saber-toothed cats, which seem to have been much like modern cats but with a different mode of killing their prey?

An international team of researchers, led by Professor Christine Janis from Bristol’s School of Earth Sciences, have performed a series of studies on the skull and teeth of this animal and have come to a different conclusion. Their findings are published in the journal PeerJ.

Professor Janis said: “The title of this paper, ‘An Eye for a Tooth’, sums up how we think this animal has been perceived.

“It has impressive canines, for sure: but if you look at the whole picture of its anatomy, lots of things simply don’t add up. For example, it just about lacks incisors, which big cats today use to get meat off the bone, and its lower jaws were not fused together.

“In addition, the canines of Thylacosmilus were different from the teeth of other saber-toothed mammals, being triangular in shape like a claw rather than flat like a blade.”

A statistical study, comparing aspects of the skull and teeth of Thylacosmilus with both present-day big cats and a diversity of extinct saber-toothed cats, confirmed suspicions about the differences from its placental supposed counterparts.

Co-author Borja Figueirido of the University of Málaga (Spain) added: “The skull superficially looks rather like that of a saber-toothed placental.

“But if you actually quantify things, it becomes clear that Thylacosmilus’ skull was different in many details from any known carnivorous mammal, past or present.”

Detailed biomechanical studies comparing the skulls of Thylacosmilus and Smilodon, simulating performance under different conditions, were also revealing.

Stephan Lautenschlager from the University of Birmingham, the contributing author on the paper who performed these analyses, said: “Previous studies by other researchers have shown Thylacosmilus to have had a weaker bite than Smilodon.

“But what we can show is there was probably a difference in behaviour between the two species: Thylacosmilus’ skull and canines are weaker in a stabbing action than those of Smilodon, but are stronger in a ‘pull-back’ type of action. This suggests that Thylacosmilus was not using its canines to kill with, but perhaps instead to open carcasses.”

Finally, the other teeth of Thylacosmilus also pose problems for the interpretation of this animal as a cat-like predator, whether saber-toothed or not. Besides the puzzling lack of incisors, the molars are small, and did not wear down along the sides as seen in an animal feeding on meat.

Larisa DeSantis from Vanderbilt University (USA), who conducted a detailed dental study, added: “The molars tend to wear flat from the top, rather like you see in a bone crusher.

“But if you examine the detailed microwear on tooth surfaces, it’s clear that it was eating soft food. Its wear is most similar to that of cheetahs which eat from fresh carcasses and suggests an even softer diet than fed to captive lions.

“Thylacosmilus was not a bone-crusher and may have instead specialised on internal organs.”

Professor Janis said: “It’s a bit of a mystery as to what this animal was actually doing but it’s clear that it wasn’t just a marsupial version of a saber-toothed cat like Smilodon.

“In addition to the differences in the skull and the teeth, it was also short-legged and stiff-backed, and lacked retractile claws, so it would have had difficulties in pursuing its prey, pouncing on it and holding on to it. I suspect it was some sort of specialised scavenger.

“It may have employed those canines to open carcasses and perhaps also used a big tongue to help extract the innards: other mammals that have lost the incisors, like walruses and anteaters, also have big tongues that they use in feeding.”

When Thylacosmilus lived on the plains of Argentina five million years ago, it would have inhabited a very different type of ecosystem to any modern one. Then the big predators were huge flightless birds, the “terror birds” or phorusrachiformes, now all extinct. Life in the past may have been very different to the present day.

Borja Figueirido added: “In Africa today it’s the mammals who are the killers and the big birds, like vultures, are the scavengers. But perhaps five million years ago in Argentina it was the other way around, and it was the mammals who were the scavengers.”

Racism and police brutality update


This 25 June 2020 video from Britain says about itself:

From George Floyd to Slavery: Jeremy Corbyn in conversation with Remi Kapo

“The price of change is always paid in blood

Remi Kapo’s latest book ‘Torrents of Fire‘ is out now.

MAXINE WATERS RIPS TRUMP FOR FOCUS ON DEAD CONFEDERATES In a scathing statement, Rep. Maxine Waters on Thursday lashed Trump’s inaction against the coronavirus pandemic as he instead focuses his energies on protecting statues honoring dead traitors and slaveholders. “We are left with Donald Trump, an incompetent and heartless man who is more focused on saving statues of slaveholders, Confederate generals, and racists than protecting the health of living and breathing American,” the California Democrat said. [HuffPost]

TRUMP TALKS LIKE HE’S RUNNING FOR PRESIDENT OF THE CONFEDERACY Trump is running for a second term as president of the United States, but in recent weeks he’s spoken and written as if he wants to be the next president of the Confederacy. Amid a national uproar over the killing of a Black man by a white Minneapolis police officer and an erosion in his own polling numbers, Trump has made the cornerstone of his response a vow to protect monuments and memorials to the leaders of the treasonous rebellion that cost 750,000 lives for the sole purpose of keeping Blacks enslaved. [HuffPost]

TRUMP HAS DISMANTLED MORE MONUMENTS THAN ANY PROTEST President Donald Trump is promising lengthy prison sentences for anyone who destroys or dismantles a monument to a slave-owning president or leader of the Confederacy. But it is Trump who has done the most damage to national monuments, dismantling or desecrating four federally protected land and water sites with significant cultural, archeological and natural resources. Those rollbacks include carving more than 2 million acres from a pair of protected national monuments in Utah — Bears Ears and Grand Staircase-Escalante. [HuffPost]

These TV Dramas Tackled Police Violence Head On, But Hollywood Backed Away. The showrunners of “The Red Line,” “Seven Seconds” and “Shots Fired” discuss how representation in the industry affects a whole lot more than casting: here.

This 24 June 2020 video from the USA says about itself:

Black Child Barred from Eating at Baltimore Restaurant | NowThis

This Black child in athletic clothes was barred from eating at a Baltimore restaurant while a white child in a similar outfit was allowed entry.

Atlas Restaurant Group stated they are changing their dress code policy and that it will no longer be enforced for children under 12.

Facebook failing to contain content from far-right ‘Boogaloo’ movement, experts say.

New Zealand Police brutally attack young man in Auckland. By Tom Peters, 26 June 2020. The attack on an unarmed Maori man in Auckland follows mass protests against police violence and the arming of officers.

Timber rattlesnake conservation, new research


This March 2020 video from the USA says about itself:

Considered the most dangerous rattlesnake in the world because of its potent venom and proximity to humans, learn all about the unique adaptations and ecological value of the timber (or canebrake) rattlesnake in today’s episode of The Wild Report!

From Penn State Unversity in the USA:

Habitat for Rattlesnakes: Sunnier but Riskier

Conservation efforts to open up rattlesnake habitat bring in much-needed sunlight but could attract more threatening predators

June 24, 2020

Conservation efforts that open up the canopy of overgrown habitat for threatened timber rattlesnakes — whose venom is used in anticoagulants and other medical treatments — are beneficial to snakes but could come at a cost, according to a new study by researchers at Penn State and the University of Scranton. The researchers confirmed that breeding areas with more open canopies do provide more opportunities for these snakes to reach required body temperatures, but also have riskier predators like hawks and bobcats. The study, which appears in the June issue of the Journal of Herpetology, has important implications for how forest managers might open up snake habitat in the future.

Timber rattlesnakes are a species of conservation concern in Pennsylvania and are considered threatened or endangered in many of the northern states within their range. Like other ectothermic animals, snakes do not produce their own body heat and must move to warmer or cooler areas to regulate their temperature. Timber rattlesnakes typically use sunny, rocky forest clearings to breed, however many of these “gestation sites” are becoming overgrown with vegetation, blocking much-needed sunlight.

“Pregnant timber rattlesnakes typically maintain a temperature 6 to 8 degrees Celsius higher than normal so that their embryos can develop,” said Christopher Howey, assistant professor of biology at the University of Scranton and former postdoctoral researcher at Penn State. “If a gestation site doesn’t provide enough opportunities for snakes to reach that temperature, a snake might abort its litter, or babies might be born too small or later in the season, which reduces their chances of obtaining an essential first meal before hibernation. We wanted to understand if existing conservation efforts to open up the canopy in gestation sites actually do provide more thermal opportunities for snakes, as intended, and if these efforts impact predation risk.”

The research team first quantified thermal opportunities for rattlesnakes in known gestation sites that had open or closed canopies. They logged temperatures within thermal models — essentially a copper tube painted to have similar reflectivity and heat absorbance to a snake — placed in areas where the researchers had seen snakes basking.

“As expected, we found that gestation sites with more open canopies did indeed provide more opportunities for snakes to reach optimal temperatures,” said Tracy Langkilde, professor and head of biology at Penn State. “This confirms that conservation efforts to open up the canopy do what they are intended to do. But we also found that this might come at a cost, in the form of more threatening predators.”

The research team also placed foam models painted like rattlesnakes at gestation sites and monitored for predators using trail game cameras — remote cameras that are triggered by movement. While there was a similar overall number of predators at sites with open canopies and closed canopies, the more threatening species — red-tailed hawks, fishers, and bobcats — only appeared at open sites.

“Our results suggest that there are tradeoffs to any management strategy and that by opening up a gestation site, we may inadvertently put more predation risk on a species,” said Julian Avery, assistant research professor of wildlife ecology and conservation at Penn State. “Our models were slightly less visible to potential predators than actual snakes, so our estimates of predation risk are probably conservative, and the tradeoff may be more pronounced than what we observed.”

Less threatening predators — raccoons and black bears — appeared at sites with both open and closed canopies.

“As far as we know, this is the first time that a black bear has been observed preying on a rattlesnake, or at least a model,” said Howey. “Until now, we always thought that black bears avoided rattlesnakes, but we observed one bear attack two models and bite into a third.”

The team suggests that forest managers should balance canopy cover and predation risk during future conservation efforts, for example by selectively removing trees that block direct sunlight but that do not considerably open up the canopy.

Improving conservation efforts at rattlesnake gestation sites is particularly important because, as far as the researchers know, snakes return to the same sites year after year to breed. If a gestation site decreases in quality, they might leave the site to find a new area, but it is unclear how successful these efforts are and the act of moving to new sites could increase contact with humans.

The researchers are currently radio-tracking actual snakes and directly manipulating the canopy cover to better understand how snakes behave in response to predators at sites with open vs. closed canopies.

“Timber rattlesnakes are an important part of the ecosystem, and where you have more rattlesnakes, you tend to have lower occurrences of Lyme disease because the snakes are eating things like chipmunks and mice which are the main vectors for the disease,” said Howey. “Rattlesnake venom is also used in anticoagulants, in blood pressure medicine, and to treat breast cancer. Our research will help us refine how we conserve these important animals.”

Trump, Bolsonaro making COVID-19 disaster even worse


This 25 June 2020 video from the USA says about itself:

How U.S. and Brazil Leadership That “Neglects Science” Led to Hemisphere’s Worst Coronavirus Crises

As coronavirus infections worldwide approach 10 million, nearly half can be found in the two largest countries in the Americas: the United States and Brazil, which now has the worst infection rate in the world and could surpass the U.S. death toll next month.

“What we see in the country is a reflection of the leadership that we have,” says Marcia Castro, professor of demography, chair of the Department of Global Health and Population at the Harvard T.H. Chan School of Public Health and co-chair of Harvard’s Brazil Studies Program, noting far-right President Jair Bolsonaro has downplayed the pandemic’s severity and undermined efforts to enforce protective measures. We also discuss the country’s participation in vaccine trials, the impact of the crisis on Brazil’s Indigenous population, and the spike in COVID in the three most populous U.S. states of California, Texas and Florida.

STATES PAUSE REOPENINGS AS VIRUS RAGES The coronavirus crisis deepened in Arizona and the governor of Texas began to backtrack after making one of the country’s most aggressive pushes to reopen, as the daily number of confirmed cases smashed the peak reached during late April. Florida’s governor also said he’d delay the next phase of reopening. The U.S. case numbers, probably influenced by expanded testing, show the virus is making a community spread comeback. Daily deaths, hospitalizations and the percentage of tests coming back positive have been rising over the past few weeks, mostly in the South and West. [AP]

TRUMP ASKS SUPREME COURT TO KILL OBAMACARE AMID PANDEMIC The Trump administration filed a brief Thursday night calling on the U.S. Supreme Court to invalidate the Affordable Care Act — which allows millions of Americans to get health insurance coverage — just as the nation hit a record for new COVID-19 cases in a single day. Solicitor General Noel Francisco argued in a brief that because Congress in 2017 invalidated the law’s individual coverage mandate — by dropping a tax penalty for those without health insurance — the “entire ACA thus must fall.” Pelosi ripped the president for “unfathomable cruelty.” [HuffPost]

TEXAS PUTS REOPENING ON ‘PAUSE’ AS COVID-19 CASES SOAR Gov. Greg Abbott halted elective surgeries in Texas’ biggest counties and said the state would “pause” its aggressive re-opening as it deals with a surge in coronavirus cases and hospitalizations that has made it one of the nation’s virus hot spots. The suspension of elective surgeries is designed to protect hospital space in the Dallas, Houston, Austin and San Antonio areas. Statewide, the number of COVID-19 patients has more than doubled in two weeks.  [AP]

 

Global warming benefits Greenland wolf spiders


This 2019 video says about itself:

Arctic Wolf Spiders‘ Changing Diet May Help Keep Arctic Cool & Lessen Some Impacts of Global Warming

Ecologist Amanda Koltz has a special interest in climate change and spiders. Koltz said she chose to study Arctic wolf spiders because they’re fierce hunters and abundant, making them one of the most important predators in the tundra. Leaving her biology lab at Washington University in St. Louis, Koltz conducts her field research in Northern Alaska. Koltz and her team discovered that Arctic wolf spiders may buffer some of the effects of global warming by helping to ‘keep it cool’. Wolf spiders may play a role decreasing decomposition rates in a warming climate. As the Arctic warms, research shows wolf spiders may dine differently initiating a cascade of food web interactions that could potentially alleviate some impacts of global warming.

From Aarhus University in Denmark:

Spider baby boom in a warmer Arctic

June 25, 2020

Climate change leads to longer growing seasons in the Arctic. A new study, which has just been published in Proceedings of the Royal Society B, show that predators like wolf spiders respond to the changing conditions and have been able to produce two clutches of offspring during the short Arctic summer.

Arctic spiders are at the top of the food chain among invertebrates and are numerous on the Arctic tundra. They typically take several years to become adults, and only produce offspring [once].

But something is happening in the high north in these years. A lot, actually.

Climate change is more dramatic here than in no other place on Earth. The average temperature is increasing significantly and this affects the ecosystems.

Researchers have previously reported how plants bloom earlier and earlier in the season. There are also signs that species move farther north and up into the mountains.

A team of researchers led by senior researcher Toke T. Høye from the Arctic Research Centre and Department of Bioscience at Aarhus University has now shown that changes are also occurring in the reproduction of invertebrates.

For almost 20 years, researchers at the Zackenberg Research Station in north-eastern Greenland have caught wolf spiders as part of the monitoring programme Greenland Ecosystem Monitoring. The spiders were caught in small pitfall traps set up in different vegetation types.

Wolf spiders carry their eggs in a so-called egg sac. The researchers counted the number of eggs in the individual spiders’ egg sacs and compared this information with the time of the season that the animal was caught. By looking at the distribution of the number of eggs in the egg sacs throughout the season, it became clear that in some summers the spiders produced two egg sacs — a phenomenon that is known from warmer latitudes, but which has not previously been observed in the Arctic.

Arctic ecosystems are changing

“We now have the longest time series of spiders collected the Arctic. The large amount of data allows us to show how small animals in the Arctic change their life history in response to climate change,” says Toke T. Høye.

The long time series tells the researchers that the earlier the snow disappears from the ground, the greater the proportion of spiders that can produce a second clutch of offspring.

“These changes in the life history have not been seen earlier and evidence suggests that the phenomenon plays an important role for Arctic insects and spiders,” Toke T. Høye says.

The researchers see the spiders’ response to climate change as an ability to adapt to the new conditions.

Wolf spiders feed on small organisms such as springtails in the soil. If there are more spiders — or insects — in the future Arctic, it can have an influence on the food chains on land.

“We can only speculate about how the ecosystems change, but we can now ascertain that changes in the reproduction of species are an important factor to include when we try to understand how Arctic ecosystems react to the rising temperatures on the planet,” Toke T. Høye says.

British Conservatives mismanage COVID-19 disaster, doctors say


This 23 June 2020 video from England says about itself:

Healthworkers take a knee in solidarity with Black Lives Matter

Windrush Day 2020, 5pm: Health workers at St Thomas’s Hospital, London, take a knee in solidarity with Black Lives Matter. Simultaneous actions also took place at King’s, South London and Maudsley, and Lewisham hospitals.

Mark Boothroyd, Unite branch secretary for Guy’s and St Thomas’, said: “The NHS has the same problems of systemic racism as every other part of society.

“With over 50% of nursing staff in London being from BME backgrounds and directly affected by this, it is important staff can show their support for Black Lives Matter, and push their own employers to make changes to tackle the ongoing issue of racism in the NHS.”

Dame Donna Kinnair, RCN chief executive and general secretary, said: “The best way to honour the legacy of Windrush Day is to ensure no nurse, or health and care worker, who trained overseas, and helped in this pandemic, feels alien in this country.

“Granting automatic, indefinite leave to remain to international health and care workers who helped tackle this virus should be instinctive.

“The services and support that they provide, though brought to the fore through this pandemic, have always been essential. They are, and always will be, key workers.”

From daily News Line in Britain today:

‘Abysmal response’ to corona – experts warn antibody tests are ‘invalid’

EXPERTS have heavily criticised the Tories’ ‘ad hoc system’ for coronavirus tracking, testing and contact tracing, stating that the government’s ‘abysmal response’ means that many suspected cases will have been missed while other professionals are questioning whether the anti-body tests fundamentally can actually tell us anything at all.

In a special report published in the British Medical Journal (BMJ) yesterday, Peter Roderick and colleagues from Newcastle University question why the government has eroded England’s established system of local infectious disease control and created a parallel system which relies on private companies for testing and contact tracing.

They are concerned by clear and reported failings in this parallel system, warning that many suspected cases will have been missed, and arguing that contact tracing and testing ‘should be led by local authorities and coordinated nationally’.

Historically, England’s system of communicable disease control has relied on experience and close cooperation between local health services and local authorities, they explain.

That local system has gradually been eroded over several decades. But instead of prioritising and rebuilding this system at the start of this epidemic, the government has created a separate system which steers patients away from GPs, avoids local authorities, and relies on commercial companies and laboratories to track, test, and contact trace.

Questioning the validity of the antibody test, Oxford GP Dr Helen Salisbury commented: ‘We don’t know what the results mean. There are increasing numbers of people who are fairly sure that they have had the virus and some who have even had positive tests for the actual antigen when they were ill who are getting negative antibody tests which is really interesting. So although having a positive test may tell you that you did have it, having a negative test, we are not sure about that.

‘We normally do tests when we know what to do with the answers. I am really quite concerned that patients who understandably want to have this test are going to be looking to GPs to both counsel them before they have had a test and explain the results afterwards and that is going to take up a lot of our time, and we do not have the answers to give them.

‘So, everyone really wanted there to be this idea of an immunity passport: You have got antibodies, you are safe. It is just not true, we just don’t know that, and people are going to be very confused.

‘We can’t as clinicians and scientists, work out a good reason for this sudden “everyone can have an anti-body test rhetoric”, because it does not make sense.

‘It does, however, make sense to be doing lots of tests in the context of research, if we can put together who has had symptoms, who has had a positive test after having the virus before, what do their antibodies look like and what happens next.

‘If we collected all that data and did research on it, which people are doing, that would make sense.

‘But just to roll out the test for anyone who would like it, which is really what we have been told, does not make any sense at all.’

William Irving, Professor of Virology, Faculty of Medicine & Health Sciences at the University of Nottingham agreed. He said: ‘When you have a test where when the result is negative it makes no difference and when the result is positive it makes no difference, there isn’t really a huge logic to doing the test in the first place.

‘We are under pressure, in the NHS, to be careful with resources, to only do tests which are meaningful, which the clinician can interpret, which will help with patient care.

‘The antibody test fails on those accounts.

‘The presence of antibodies does not tell you anything about whether the patient is protected against any future infection.’

Old bugs, young bugs, different colours


This May 2019 video says about itself:

The green shield bug – Palomena prasina – is a European shield bug species in the family Pentatomidae. The name might equally apply to several other species in the tribe Nezarini, or if referred-to as a “green stink bug”, it might more appropriately belong to the larger North American bug, Acrosternum hilare.

From the University of Melbourne in Australia:

Bugs resort to several colors to protect themselves from predators

Colorful bugs look very different as young and adults, but why?

June 25, 2020

Summary: New research has revealed for the first time that shield bugs use a variety of colors throughout their lives to avoid predators. For years it has been thought that animals living in the same environment — like nymphs and adults of the same species — should use similar warning colors, not different ones.

New research has revealed for the first time that shield bugs use a variety of colours throughout their lives to avoid predators.

Shield bugs are often bright, colourful insects that use colours to warn off their distastefulness to predators. The paper, published in Proceedings of the Royal Society B, found that it is impossible to predict how an adult bug will look like based on their colour when young.

“We found that in most species, the same individual bug will use different colour combinations as nymphs — young bugs — and adults, going for example from red and green to yellow and green,” said lead author and ecologist, Dr Iliana Medina, from the University of Melbourne’s School of Biosciences.

“This is significant because many of these species use colour to warn predators that they are distasteful, and for years it has been thought that animals living in the same environment — like nymphs and adults of the same species — should use similar warning colours, not different ones.”

The joint research between scientists at the University of Melbourne and the Australian National University combined information on colour in young and adults for more than 100 species of shield bugs worldwide. They then used fieldwork in Canberra, with white-winged choughs, to measure how likely these birds were to attack adult and nymphs of one Australian species of shield bug, the cotton harlequin bug.

Experiments were also conducted in the aviary, training two-week-old chicks to see how fast they learned to avoid nymphs and adults, then testing whether their previous experience with adults could reduce attack rates on nymphs.

“Our experiments with the cotton harlequin bug showed that predators could quickly learn to avoid both types of colour signals from nymphs and adults, but nymphs get a larger benefit,” Dr Medina said.

“Although young and adult cotton harlequin bugs have different colours, previous experience with adults make chicks less likely to attack the nymphs. Also, chicks and wild predators that have never seen the insects before do not show much interest in eating them. The colours in these insects are a great strategy against predators.”

Many animals such as frogs, insects and sea slugs use bright colourations to advertise toxicity or distastefulness. In theory, warning signals of prey that live in the same environment should be the same because predators can learn more effectively to avoid one type of pattern, instead of many different ones.

While this idea has been used to explain the great examples of mimicry in nature, and why distantly related species end up having the same warning colours, such as black and red, or black and yellow, researchers say there are multiple examples of variation in local warning signals and an overlooked type of variation is that across life stages.

“If predators were able to learn to avoid only one type of warning colour, we would expect nymphs and adults to look similar in many species,” Dr Medina said. “What our findings show, however, is that the wide colour variation in shield bugs is probably the result of predators being able to learn to avoid different types of colourful signals.”

Elijah McClain, another United States police killing


Rashiaa Veal holds a sign honoring her cousin Elijah McClain at a press conference in front of the Aurora Municipal Center on October 1, 2019. Photo Credit: Andy Cross/MediaNewsGroup/The Denver Post via Getty Images

This photo from Colorado in the USA shows Rashiaa Veal holding a sign honoring her cousin Elijah McClain at a press conference in front of the Aurora Municipal Center on October 1, 2019. Photo credit: Andy Cross/MediaNewsGroup/The Denver Post via Getty Images.

From Colorlines in the USA:

Millions Demand Justice for Elijah McClain Following Death in Police Custody

State officials will reexamine the 2019 death of the 23-year-old, who died after Aurora, Colorado, officers put him in a chokehold.

By Shani Saxon, June 25, 2020 2:31PM ET

Colorado Governor Jared Polis announced on June 24 that his administration will launch an investigation into the death of Elijah McClain, a 23-year-old Black man killed in August 2019 following an encounter with police officers, CNN reports. The announcement came after millions of people signed a Change.org petition demanding an independent investigation into McClain’s death.

Reports CNN:

On August 24, 2019, McClain was stopped by three White officers as he walked home from a convenience store, after a 911 caller described a “suspicious person”, according to a police overview of the incident. McClain resisted officer contact, the report says, and a struggle ensued. On one of the officers’ body cameras, McClain is heard saying, “I’m an introvert, please respect the boundaries that I am speaking.” Bodycam video shows McClain telling officers that he was trying to stop his music to listen to them, then they begin to arrest him. One officer is heard telling another, “He just grabbed your gun, dude.”

According to an overview of the incident that police provided to CNN, an officer placed McClain in a chokehold, causing him to briefly lose consciousness:

lose consciousness:

They released the hold, the report says, and [McClain] began struggling again. When paramedics arrived at the scene they administered ketamine to sedate McClain, the report said. According to a letter from the district attorney, McClain suffered a heart attack while in the ambulance, and he was declared brain dead three days later. An autopsy did not determine a cause of death but listed intense physical exertion and a narrow left coronary artery as contributing factors, according to the police overview. The coroner found the amount of ketamine in his system to be a therapeutic amount.

In addition to Polis’ new investigation into this case, the city of Aurora is planning its own investigation, according to CNN. “The mayor, City Council and city manager are working to initiate a new independent, external review of the actions of police, firefighters and paramedics in the Elijah McClain case,” a state official told CNN. “We are considering a team of experts from across the country to be involved and provide insight from different perspectives, but the exact participants have not been selected yet.”

Mari Newman, an attorney representing the McClain family, is calling for charges to be brought against the officers involved in McClain’s death. “He was an angel among humans,” Newman said of McClain while speaking to CNN via Denver’s KCNC. “He would go to play his violin on lunch hour to animals who were waiting to be adopted so they wouldn’t be lonely.”

Newman added, “It shouldn’t take millions of people signing a petition, and it shouldn’t take international media attention for elected officials to do their jobs.”

The three white men who killed black jogger Ahmaud Arbery on February 23 were indicted Wednesday on murder charges by a Georgia grand jury. The men were not arrested and charged until last month, after a video of the brutal killing went viral on social media and prompted nationwide protests: here.

Aurora, Colorado, police attack protesters after investigation reopened into 2019 death of Elijah McClain: here.