Ancient trilobites’ social life, new research


This June 2017 video from the USA says about itself:

Trilobites are famous not just because they were so beautifully functional, or because they happened to preserve so well. They’re known the world over because they were everywhere!

From the CNRS in France:

Arthropods formed orderly lines 480 million years ago

October 17, 2019

Researchers studied fossilized Moroccan Ampyx trilobites, which lived 480 million years ago and showed that the trilobites had probably been buried in their positions — all oriented in the same direction. Scientists deduced that these Ampyx processions may illustrate a kind of collective behavior adopted in response to cyclic environmental disturbances.

Though our understanding of the anatomy of the earliest animals is growing ever more precise, we know next to nothing about their behaviour. Did group behaviour arise recently or is it primeval? To answer this question, researchers from the CNRS, the University of Poitiers, UBO, Claude Bernard Lyon 1 University*, Cadi Ayyad University (Marrakech, Morocco), and the University of Lausanne (Switzerland) studied fossilized Moroccan Ampyx trilobites, which lived 480 million years ago. They showed that the trilobites had probably been buried in their positions — all oriented in the same direction, in orderly lines, maintaining close contact with each other through their long spines — during storms.

By comparing this observation with the behaviour of living animals such as North American spiny lobsters, the scientists deduced that these Ampyx processions may illustrate a similar kind of collective behaviour — adopted in response to cyclic environmental disturbances like storms or to chemical signals associated with reproduction.

This example would seem to suggest that group behaviour is of ancient origin and, from an early date, likely conferred an evolutionary advantage on the first animals, allowing them to survive environmental stress and improve their reproductive chances.

*- From the Laboratoire de Géologie de Lyon: Terre, Planètes, Environnement (CNRS / ENS de Lyon / Université Claude Bernard Lyon 1), the Laboratoire Géosciences Océan (CNRS / Université Bretagne Occidentale / Université Bretagne Sud), and the Institute of Chemistry of Materials and Media of Poitiers (IC2MP (CNRS / Université de Poitiers).

News on the far right, update


This 1 June 2019 video says about itself:

Germany: Counter-protest dwarfs neo-Nazi march in Chemnitz

Far-right activists were met with scores of counter-protesters as they marched through Chemnitz on Saturday, marking ‘The Day of the German Future.’ Around 250 neo-Nazi protesters marched through the city centre, carrying flags of Imperial Germany and shouting xenophobic slogans such as ‘Germany for Germans, foreigners out‘. The protest was countered by around a 1,300-strong rally who attempted to disrupt the march, even scuffling with the police at one point. Despite tensions, an escalation was averted.

It took YouTube more than a week to take action against a propaganda video on its site produced by the Atomwaffen Division (AWD) — the neo-Nazi terrorist organization under FBI investigation and linked to five murders in the United States: here.

It took YouTube a lot less time to censor a non-violent anti-fascist video.

Germany Shooter ‘Would Have Killed More People’ With Access To Better Guns. The man accused of shooting two people to death in Halle, Germany, this week shares a lot of characteristics with American mass shooters: He’s a bigot with delusions of grandeur, and is part of an online community that fervently supports his hate. But there’s one thing that set him apart: here.

How the German synagogue shooter’s manifesto follows a far-right playbook [Vice]

Jury hangs on hate crime charges against racist New Jersey police chief [HuffPost]

‌A far-right candidate jolts the Canadian election [New York Times]

Flying squirrel at Cornell USA bird feeder


This video from New York State in the USA says about itself:

Flying Squirrel Is Early Morning Visitor To Cornell Lab FeederWatch Cam – Oct. 15, 2019

Thanks the Cornell Lab FeederWatch cam’s new night vision feature, we can now see all the visitors who stop by the feeder after the sun goes down! Watch this flying squirrel zip onto the platform, where it would stay feasting for about 10 minutes before venturing out of view.

The Cornell Lab of Ornithology writes:

Since 2012, the Cornell Lab FeederWatch cam has been known for its binge-worthy broadcast of our feathered friends from the Treman Bird Feeding Garden right outside our visitor center. We’re excited to announce that the cam you know and love has just received a 4K ultra high definition facelift! Tune in now for crisp, colorful views of your favorite Northeastern feeder birds in the highest resolution available. Thanks to the new cam’s night vision capabilities, you can stay up late and see all the action after the sun goes down (including late-nite visits from flying squirrels, see below). Watch cam here.

Neanderthal discovery on Naxos island, Greece


This 14 April 2018 video, in English with Greek subtitles, says about itself:

Carter’s Corner #6 – Neanderthals on Naxos!

From McMaster University in Canada:

Scientists find early humans moved through Mediterranean earlier than believed

October 16, 2019

An international research team led by scientists from McMaster University has unearthed new evidence in Greece proving that the island of Naxos was inhabited by Neanderthals and earlier humans at least 200,000 years ago, tens of thousands of years earlier than previously believed.

The findings, published today in the journal Science Advances, are based on years of excavations and challenge current thinking about human movement in the region — long thought to have been inaccessible and uninhabitable to anyone but modern humans. The new evidence is leading researchers to reconsider the routes our early ancestors took as they moved out of Africa into Europe and demonstrates their ability to adapt to new environmental challenges.

“Until recently, this part of the world was seen as irrelevant to early human studies but the results force us to completely rethink the history of the Mediterranean islands,” says Tristan Carter, an associate professor of anthropology at McMaster University and lead author on the study. He conducted the work with Dimitris Athanasoulis, head of archaeology at the Cycladic Ephorate of Antiquities within the Greek Ministry of Culture.

While Stone Age hunters are known to have been living on mainland Europe for over 1 million years, the Mediterranean islands were previously believed to be settled only 9,000 years ago, by farmers, the idea being that only modern humans — Homo sapiens — were sophisticated enough to build seafaring vessels.

Scholars had believed the Aegean Sea, separating western Anatolia (modern Turkey) from continental Greece, was therefore impassable to the Neanderthals and earlier hominins, with the only obvious route in and out of Europe was across the land bridge of Thrace (southeast Balkans).

The authors of this paper suggest that the Aegean basin was in fact accessible much earlier than believed. At certain times of the Ice Age the sea was much lower exposing a land route between the continents that would have allowed early prehistoric populations to walk to Stelida, and an alternative migration route connecting Europe and Africa. Researchers believe the area would have been attractive to early humans because of its abundance of raw materials ideal for toolmaking and for its fresh water.

At the same time however, “in entering this region the pre-Neanderthal populations would have been faced with a new and challenging environment, with different animals, plants and diseases, all requiring new adaptive strategies,” says Carter.

In this paper, the team details evidence of human activity spanning almost 200,000 years at Stelida, a prehistoric quarry on the northwest coast of Naxos. Here early Homo sapiens, Neanderthals and earlier humans used the local stone (chert) to make their tools and hunting weapons, of which the team has unearthed hundreds of thousands.

Reams of scientific data collected at the site add to the ongoing debate about the importance of coastal and marine routes to human movement. While present data suggests that the Aegean could be crossed by foot over 200,000 years ago, the authors also raise the possibility that Neanderthals may also have fashioned crude seafaring boats capable of crossing short distances.

This research is part of the Stelida Naxos Archeological Project, a larger collaboration involving scholars from all over the world. They have been working at the site since 2013.

For more on the project, visit the Stelida Naxos Archeological Project’s website.

Mosquito-borne diseases hurt poor people more


This video says about itself:

Baltimore: ‘This is what poverty in the US looks like’ – BBC News

Ian Pannell reports from the city of Baltimore, where 25% of the population lives in poverty.

This report was first published in February 2017.

From the Cary Institute of Ecosystem Studies in the USA:

In Baltimore, lower income neighborhoods have bigger mosquitoes

Larger mosquitoes better at transmitting disease, put residents at risk

October 16, 2019

Low-income urban neighborhoods not only have more mosquitoes, but they are larger-bodied, indicating that they could be more efficient at transmitting diseases. So reports a Cary Institute of Ecosystem Studies-led study, published in the Journal of Medical Entomology, investigating how socioeconomics influences mosquito-borne disease risk in Baltimore, Maryland.

As part of the Baltimore Ecosystem Study, Cary Institute scientists have been investigating how environmental and social conditions regulate mosquito numbers. Tiger mosquitoes (Aedes albopictus) were the focus of this study. This invasive species dominates in urban areas, where it is an aggressive day-biter that targets people and can transmit an array of viruses including dengue fever, Zika, chikungunya, Eastern Equine Encephalitis, and West Nile virus.

Cary Institute disease ecologist Shannon LaDeau, senior author on the study, explains, “More people are living in cities. At the same time, many other species are also adapting to city living. Invasive species like the tiger mosquito increasingly thrive in temperate urban areas, living among us and fundamentally altering the risk of local disease emergence. ”

Previous studies have found that wing length is an accurate proxy for body size in mosquitoes, and body size influences traits that are important to disease transmission. LaDeau and colleagues measured wing length of tiger mosquitoes trapped across a continuum of neighborhoods in Baltimore, Maryland. Results where clear: mosquitoes from less affluent blocks were larger than mosquitoes from more affluent blocks.

Block-to-block differences in abandoned buildings, vacant lots, and trash removal influence mosquito populations, biting patterns, and disease risk. LaDeau explains, “People living in neighborhoods with abandoned infrastructure are more at risk, because tiger mosquitoes flourish in less managed landscapes. They can breed in the water filling a bottle cap or crushed can. Abundant juvenile habitat sets the stage for healthy adult mosquitoes.”

Adult female tiger mosquitoes were collected from 13 residential blocks in Baltimore over the course of three summers. Trapping took place in June and July, 2015-2017. Blocks were distributed among five neighborhoods ranging in socioeconomic status — with varying levels of management and occupancy.

For each block, the team measured the percentage of abandoned structures and counted discarded container habitats — defined as any object that could potentially hold water — to determine whether differences in these features across blocks influenced numbers of juvenile tiger mosquitoes and adult female body size.

Over the three years of the study, 1097 mosquitoes were collected and measured. The team found that mosquitoes from blocks with higher abandonment had larger wings than those collected on more affluent blocks with less abandonment. Wing length differences of less than one millimeter can affect traits like fecundity, longevity, and ability to spread disease.

They also counted juvenile tiger mosquitoes and related these numbers to the abundance of unmanaged container habitats in a block. Less affluent blocks averaged 400 habitats per square kilometer with 80% containing mosquito larvae. More affluent blocks averaged only 50 containers per square kilometer with less than 5% containing mosquito larvae.

Lead author Grace Katz worked on the project as a high school intern and was responsible for measuring hundreds of wings. She explains, “Understanding how landscape features influence mosquito size and their ability to make us sick is important if we want to better manage mosquitoes in cities.”

LaDeau concludes, “The trends we’re seeing in mosquito numbers and body size map onto socioeconomic patterns at the block-level. There are environmental justice and equity implications at play. Residents of less affluent neighborhoods are exposed to more mosquitoes. If those mosquitoes have greater longevity or fitness, as previous studies on body size suggest, then residents may be at a greater risk of contracting mosquito-borne illnesses. There’s a pressing need to address infrastructure abandonment and waste management to protect all residents.”

*Mosquito samples used for this study were collected with the financial support of the National Science Foundation Baltimore Ecosystem Study (NSF-LTER DEB 1027188) and the NSF Coupled Natural Human Systems Program (DEB 1211797).

How big dinosaurs survived heat


This 16 September 2018 video says about itself:

The Biggest Dinosaurs Of All Time

Dinosaurs are some of the biggest land-dwelling animals to ever exist on Earth. When you picture a dinosaur, you might imagine a 13-meter long T. rex or a Titanosaur the size of an airplane. But the first dinosaurs would have only come up to your knee. It turns out that sauropods, like Brontosaurus, developed special adaptations that allowed them to tower over the competition.

From Ohio University in the USA:

Huge dinosaurs evolved different cooling systems to combat heat stroke

Researchers use 3D imaging to discover multiple heat exchangers in dinosaur heads

October 16, 2019

Different dinosaur groups independently evolved gigantic body sizes, but they all faced the same problems of overheating and damaging their brains. Researchers from Ohio University’s Heritage College of Osteopathic Medicine show in a new article in the Anatomical Record that different giant dinosaurs solved the problem in different ways, evolving different cooling systems in different parts of the head.

“The brain and sense organs like the eye are very sensitive to temperature,” said Ruger Porter, Assistant Professor of Anatomical Instruction and lead author of the study. “Animals today often have elaborate thermoregulatory strategies to protect these tissues by shuttling hot and cool blood around various networks of blood vessels. We wanted to see if dinosaurs were doing the same things.”

Many of the famous gigantic dinosaurs — such as the long-necked sauropods or armored ankylosaurs — actually evolved those big bodies independently from smaller-bodied ancestors. “Small dinosaurs could have just run into the shade to cool off,” said study co-author Professor Lawrence Witmer, “but for those giant dinosaurs, the potential for overheating was literally inescapable. They must have had special mechanisms to control brain temperature, but what were they?”

The answer turned out to be based in physics, but still part of our everyday experience. “One of the best ways to cool things down is with evaporation,” Porter said. “The air-conditioning units in buildings and cars use evaporation, and it’s the evaporative cooling of sweat that keeps us comfortable in summer. To cool the brain, we looked to the anatomical places where there’s moisture to allow evaporative cooling, such as the eyes and especially the nasal cavity and mouth.”

To test that idea, the team looked to the modern-day relatives of dinosaurs — birds and reptiles — where studies indeed showed that evaporation of moisture in the nose, mouth, and eyes cooled the blood on its way to the brain.

Porter and Witmer obtained carcasses of birds and reptiles that had died of natural causes from zoos and wildlife rehabilitation facilities. Using a technique developed in Witmer’s lab that allows arteries and veins to show up in CT scans, they were able to trace blood flow from the sites of evaporative cooling to the brain. They also precisely measured the bony canals and grooves that conveyed the blood vessels.

“The handy thing about blood vessels is that they basically write their presence into the bones,” Porter said. “The bony canals and grooves that we see in modern-day birds and reptiles are our link to the dinosaur fossils. We can use this bony evidence to restore the patterns of blood flow in extinct dinosaurs and hopefully get a glimpse into their thermal physiology and how they dealt with heat.”

“The discovery that different dinosaurs cooled their brains in a variety of ways not only provides a window into the everyday life of dinosaurs, it also serves as an exemplar of how the physical constraints imposed by specific environmental conditions have shaped the evolution of this diverse and unique group,” said Sharon Swartz, a program director at the National Science Foundation, which funded the research. “Using a combination of technological innovation and biological expertise, these researchers were able to take a direct reading from the fossil record that provides new clues about how dinosaur skeletal form and function evolved.”

This team of current and former members of WitmerLab at Ohio University has previously looked at other cases of dinosaur physiology. In 2014 and 2018, former doctoral student Jason Bourke led projects involving Porter and Witmer on breathing and heat exchange in pachycephalosaurs and ankylosaurs, respectively. Most recently, former lab doctoral student Casey Holliday led a project with Porter and Witmer that explored blood vessels on the skull roof of T. rex and other dinosaurs that also might have had a thermoregulatory function.

The new study by Porter and Witmer is a more expansive, quantitative study that shows that “one size didn’t fit all” with regard to how large-bodied dinosaurs kept their brains cool. That is, they had different thermoregulatory strategies. The researchers looked at bony canal sizes in the dinosaurs to assess the relative importance of the different sites of evaporative cooling based on how much blood was flowing through them.

A key factor turned out to be body size. Smaller dinosaurs such as the goat-sized pachycephalosaur Stegoceras had a very balanced vascular pattern with no single cooling region being particularly emphasized. “That makes physiological sense because smaller dinosaurs have less of a problem with overheating,” Porter said. “But giants like sauropods and ankylosaurs increased blood flow to particular cooling regions of the head far beyond what was necessary to simply nourish the tissues.” This unbalanced vascular pattern allowed the thermal strategies of large dinosaurs to be more focused, emphasizing one or more cooling regions.

But although sauropods like Diplodocus and Camarasaurus and ankylosaurs like Euoplocephalus all had unbalanced vascular patterns emphasizing certain cooling regions, they still differed. Sauropods emphasized both the nasal cavity and mouth as cooling regions whereas ankylosaurs only emphasized the nose. “It’s possible that sauropods were so large — often weighing dozens of tons — that they needed to recruit the mouth as a cooling region in times of heat stress,” Porter said. “Panting sauropods may have been a common sight!”

One problem that the researchers encountered was that many of the theropod dinosaurs — such as the 10-ton T. rex — were also gigantic, but the quantitative analysis showed that they had a balanced vascular pattern, like the small-bodied dinosaurs.

“This finding had us scratching our heads until we noticed the obvious difference — theropods like Majungasaurus and T. rex had a huge air sinus in their snouts,” Witmer said. Looking closer, the researchers discovered bony evidence that this antorbital air sinus was richly supplied with blood vessels. Witmer had previously shown that air circulated through the antorbital air sinus like a bellows pump every time the animal opened and closed its mouth. “Boom! An actively ventilated, highly vascular sinus meant that we had another potential cooling region. Theropod dinosaurs solved the same problem…but in a different way,” concluded Witmer.

The researchers are now expanding the project to include other dinosaur groups such as duck-billed hadrosaurs and horned ceratopsians like Triceratops to explore how thermoregulatory strategies varied among other dinosaurs and how these strategies may have influenced their behavior and even their preferred habitats.

The research was funded by National Science Foundation (NSF) grants to Witmer (part of the Visible Interactive Dinosaur Project), as well as by the Ohio University Heritage College of Osteopathic Medicine.

German nazis pretend to be police


This May 2016 video says about itself:

Germany: NPD rally mourns defeat and ‘occupation’ of Nazi Germany

The far-right National Democratic Party of Germany (NPD) held a rally in the German town of Demmin, Sunday, to commemorate the defeat of Nazi Germany and the country’s occupation, 71 years after the Red Army’s victory over Nazi Germany in 1945.

The far-right rally commemorated the Nazi loss and fall of the town … on May 1, 1945, … following the Red Army capture of the town from Nazi forces.

Translated from the Kronen Zeitung daily in Austria today:

The self-proclaimed vigilante group “Schutzzone” has been active in Germany for some time. They call themselves “the eyes and ears of the police” and claim to offer Germans security. Behind the movement is the far-right small party NPD (National Democratic Party of Germany), which is meanwhile a thorn in the side of the police. Because more and more members of that “protection zone” are hunting foreigners – and also give the impression of cooperating with the police.

A bit like the bodyguards of French President Macron, who pretend to be police in order to beat up May Day demonstrators.

Some “Schutzzone” NPD nazis in Döbeln town boast that they have ‘driven away foreigners stinking of cannabis’.

Bird migration and the moon, new research


This video from England is called Excerpts from a month in front of a European Nightjar nest in the Forest of Dean in 2018.

From Lund University in Sweden:

The moon determines when migratory birds head south

October 16, 2019

A new study from Lund University in Sweden shows that the presence or absence of moonlight has a considerable bearing on when migratory birds take flight in the autumn.

Together with colleagues at the Department of Biology at Lund University, Gabriel Norevik studied European nightjars (Caprimulgus europaeus) and how the lunar cycle and moonlight affects the departure time when the birds start their three-month-long migration flight to areas south of the Sahara.

Using miniature data loggers, the researchers charted the activity of 39 European nightjars over a one-year period. The results show that the birds are more than twice as active in their hunt for insects during moonlit nights compared with when it is dark. The study also shows that the birds begin their autumn migration south about ten days after the full moon, and that the individuals synchronise the migration and fly off more or less at the same time.

“It surprised us that the lunar cycle and the time the birds spent on hunting insects co-vary so well. This in turn affects their migration pattern in such a way that they synchronise their flight so that practically all of them fly off at the same time ten days after the full moon,” says Gabriel Norevik.

European nightjars use their sight when they hunt at night. In the moonlight they find it easier to catch flying insects and replenish their energy reserves.

The birds migratefly in three stages from Sweden and northern Europe to wintering sites south of the Sahara. Each stage follows the same pattern: when the moon provides a lot of light it more than doubles the time that the birds hunt insects, and the next stage of the migration starts ten days after the full moon.

The study of European nightjars is the first of its type to describe how a large-scale pattern such as the lunar cycle can synchronise large groups of animals to migrate at the same time. The researchers do not exclude the notion that animals other than European nightjars also adapt to the lunar cycle when they migrate.

“We will go on to examine that and what effects this type of synchronised migration has on the birds themselves and their surroundings,” says Gabriel Norevik.

‘Moonie cultist imprisoned family for years’


This 16 October 2019 British TV video says about itself:

Dutch family ‘waiting for end of time‘ found in secret room – BBC News

A family who spent nine years on a farm “waiting for the end of time” have been discovered by police in the Netherlands after one of them turned up at a local pub, reports say.

A man of 58

No, two men: the 67-year-old father, and the Austrian suspect.

and six young adults aged 18 to 25 were living at a farm in the province of Drenthe.

The mother had died years ago. The father, after a brain infarction three years ago, lay on a sickbed.

The family were found after the eldest of the children ordered beer at a bar in the nearby village of Ruinerwold.

He then told staff he needed help, broadcaster RTV Drenthe reported.

“We found six people living in a small space in the house which could be locked but wasn’t a basement“, police said in a statement late on Tuesday.

The older man [Josef B. from Austria, the suspect] has been arrested. It was not clear whether they had been there voluntarily, police added. The eldest son [who had escaped] was not there at the time, police told the BBC.

Translated from Dutch NOS TV today:

The family that lived in isolation in Ruinerwold for years is said to be affiliated with the Moonie cult. The Austrian Josef B., who is accused of having imprisoned the family, was also a member of this sect. That is what sources say to RTV Drenthe regional broadcasting organisation. …

The cult leader was South Korean pastor Sun Myung Moon. …

Not just a ‘pastor’, also an arms trade millionaire (which did not stop him from starting a phoney ‘peace movement’).

This 12 November 2018 video from the USA says about itself:

Guns For God: The Church of the AR-15

In February 2018, a small church in Pennsylvania gained international attention when they held a blessing ceremony with AR-15’s just two weeks after the Parkland School shooting triggered mass gun reform debates across the US. But where did this small fringe sect of Christianity come from and why are they now taking up arms for God? In this episode of Believers, host Charlet Duboc meets Pastor Sean Moon and the believers of the World Peace and Unification Sanctuary, a church that has origins in Korea, is based in the US, and has been accused of being a cult to understand why they believe they need guns to build God’s Kingdom on Earth.

The NOS article continues:

In the 1950s, he declared himself to be the messiah. In 1965 the movement came to the Netherlands. …

A large amount of cash is also said to have been found in the farmhouse.

What is the Moonie cult?

The Moonie cult, called the Unification Church by supporters, is a church founded in the 1950s by South Korean pastor Sun Myung Moon. He regarded himself as the messiah and became particularly known in the 1970s and 80s through marriage ceremonies where he sometimes married thousands of followers at the same time. Moon claimed he had millions of followers, but there are probably no more than 100,000.

In the past, the church was accused of brainwashing supporters and taking away their money. Moon and his wife, often accused of anti-Semitism and homophobia, were not welcome in many European countries for years. Moon died in 2012. In recent years, the movement has expanded into a business empire including the Washington Times newspaper

Far-right Donald Trump supporters. Like another cult, Falun Gong.

and the New Yorker Hotel in Manhattan.

Followers of the cult have various rituals. RTV Drenthe writes that they have to move every half hour in a circle. …

The 25-year-old son, who eventually sought help [to escape] at a cafe in Ruinerwold on Sunday evening, is said be in a different location now.

Twins with Japanese woman

A brother of suspect Josef B. tells the Austrian daily newspaper Kronen Zeitung that B. came into contact with the cult during his military service in Linz. The brothers have not spoken to each other for ten years.

Brother Franz goes on to say that Josef had twins with a Japanese woman. He is said to have abandoned them and brought them to friends in the Netherlands. Two years ago the children reportedly have tried in vain to make contact with Josef. According to his brother, B. left Austria in 2009, where he led a reclusive life.

Josef B. is suspected of being involved in the deprivation of liberty of the father and six children on the farm in Ruinerwold. He is said to have held them against their will. Today, the examining magistrate will judge whether he will be detained for longer.

UPDATE: he will be detained for at least fourteen more days. He is also accused of harming the health of the imprisoned family.

The police are investigating again today at the house in Ruinerwold. In addition, all areas in the farm are recorded digitally.

Toys

Yesterday raids were made in two buildings in Zwartsluis, about fifteen minutes drive from Ruinerwold. The family is said to have had a shop there in wooden toys, which were often made by the father. The store is said to have been closed for years.

UPDATE: The 67-year-old father, who had been active first in the Dutch, then the German Unification Church, has been arrested now as well, suspected of complicity in imprisonment and money laundering. Three older children had bled the farm before. Contrary to their younger siblings, they had been allowed to go to school.

Blue tits nesting earlier in spring


This December 2018 video is about blue tits singing.

From the University of Edinburgh in Scotland:

Warmer nights prompt forest birds to lay eggs earlier in spring

October 16, 2019

Summary: Rising night-time temperatures are causing woodland birds to build nests and lay eggs earlier in springtime, research shows.

As climate change continues to cause temperatures to rise, the breeding patterns of birds such as blue tits are being altered as evenings in spring get warmer, researchers say.

Previous research has shown that warmer springs have led birds to begin breeding earlier. However, until now, scientists had not identified the key factors that cause this behaviour.

With increasing spring warming, chicks may begin hatching after periods when caterpillars — their main food source — are most plentiful, scientists say.

Warmer temperatures are causing the peak in caterpillar numbers to occur earlier in the year, and birds like blue tits are responding too, but often not fast enough, the team says.

A team of biologists from the University of Edinburgh analysed data from 40 Scottish sites over a five-year period.

They found that birds decide when to reproduce based on night-time temperatures in springtime. Their findings suggest that colder temperatures may act as a constraint that delays the processes of building nests and laying eggs.

Blue tits were also found to lay eggs sooner if birch trees come into leaf earlier. This is some of the first evidence that birds use trees as a cue for timing breeding. Blue tits may use birch trees as a signal because they come into leaf earlier than other species, the team says.

Using data gained from two national citizen science projects, researchers found that night-time temperature and birch leafing have very similar effects on the breeding behaviour of woodland birds across the UK.

Dr Jack Shutt, of the University of Edinburgh’s School of Biological Sciences, who led the study, said: “Working out what information birds use to time breeding is key to us accurately predicting how this may change under future conditions, and what effect this will have on them.”

In birds, timing of arrival in a breeding area influences who ends up breeding and who does not. This aspect of behaviour, well-known in migratory birds, has now been studied for the first time in a non-migratory species, the blue tit. Researchers at the Max Planck Institute for Ornithology in Germany found that arrival time in the breeding area was an individual-specific and fitness-relevant trait for this resident bird species, as early-arriving individuals were more likely to breed in that year. The study suggests that it might be worthwhile to consider migration on different scales, not only as movements over thousands of kilometres to wintering grounds, but also more generally as movements between breeding and non-breeding sites: here.