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Lunar and solar eclipses make animals do strange things
Spiders, fish, birds, and bats all break with their daily routines.

For most animals, the structure of their day – and indeed their year – depends on the light-dark cycle.
These regular and rhythmic cycles in the length of days tell animals when they should be foraging, when they should be asleep, when it's time to migrate and when it's time to breed. Animals can tell all this from how many hours of daylight they experience, but the moon's cycles also strongly influence their behaviour.
The lunar synodic cycle – the moon's regular journey from full moon to full moon again over 28 nights – causes changes in the Earth's magnetic field, the moon's gravitational pull on Earth, and light levels at night. Many species can detect this and use it to synchronise their breeding. Mass spawning in corals sees tens of millions of eggs released at once on reefs to coincide with full or new moons. But what happens to animals when the moon or the sun does something unusual or unexpected, such as an eclipse?
Solar eclipses
Of all the cosmic events, solar eclipses prompt perhaps the biggest change in animal behaviour. Puzzled animals that are active during the day head back to their nighttime abodes while nocturnal animals think they've overslept. A solar eclipse occurs when the sun, moon and Earth are aligned on the same axis so that the moon completely blocks the sun. Around the world, unusual incidences of behaviour are usually reported while everyone else is watching the eclipse.
Some spider species begin to break down their webs during an eclipse, as they typically do at the end of the day. Once the eclipse has passed, they begin to rebuild them again, possibly lamenting the lack of rest in between. Similarly, fish and birds that are active during the day head for their nighttime resting places, while nocturnal bats appear, seemingly tricked by the sudden darkness.
Hippos in Zimbabwe were observed leaving their rivers during an eclipse, heading towards their nocturnal feeding grounds on dry land. Midway through their departure, the eclipse passed, daylight returned and the hippos aborted their efforts. The animals appeared agitated and stressed following the eclipse for the remainder of the day.
The moon
A lunar eclipse happens when the moon, Earth and sun are very closely aligned, with the Earth positioned between the two. As the moon passes directly behind us, Earth blocks sunlight from directly reaching the moon, causing a reddish glow to appear. These so-called "blood moons" can only occur when there is a full moon, so it's difficult to separate the impacts that lunar eclipses have on animals compared to a standard full moon.
A study in 2010 discovered that Azara's owl monkeys – a typically nocturnal species – stopped foraging in Argentina during a lunar eclipse as their world became suddenly darker. They may have struggled to see their food, or felt too unnerved to move safely through the trees.
Around three times a year, a "supermoon" occurs, which is when a full moon coincides with perigee – the point at which the moon is closest to the Earth. The moon's distance to Earth varies throughout the month, because the moon's orbit is not a perfect circle. During a perigee event, the moon is about 46,000 km closer to the Earth than during apogee – when the moon is furthest from Earth.
During a supermoon, light levels at night are around 30% brighter than at any point in the moon's monthly cycle, and it appears much larger in the sky. Our recent study found that wild barnacle geese responded to these supermoon events while they over-winter in south-west Scotland. We fitted small devices to the animals which measure their behaviour and found that the geese's heart rate and body temperature increased at night during supermoons, when typically at this time of day they'd be subdued.
The birds didn't respond to "supermoon" events when the moon was hidden by heavy cloud and the night stayed quite dark. So it appears that, a bit like with humans, the bright light of a supermoon woke the geese up, causing their heart rate and body temperature to increase, potentially in preparation for daytime.
Blood moons – despite their foreboding name – underwhelm barnacle geese.
The lunar cycle and us
For centuries, people have been fascinated about the relationship between human behaviour and the lunar cycle. Many folklores and fables were connected to our interactions with the moon, the most extreme example perhaps being that of mythical beasts such as werewolves. It isn't too surprising then that previously the term "lunatic" – from the Latin "lunaticus", meaning "of the moon" – was used to describe people deemed to be mentally ill, crazy or unpredictable, until 1930, when more appropriate and sensitive terms were introduced.
It was once believed that the lunar cycle influenced a range of strange changes to a person's physiology and the behaviour of wider society, with everything from birth rate, fertility, epilepsy and overall argumentativeness thought to be influenced. Many still believe that incidences of violent crime and general disorder increase around the time of a full moon.
A series of studies published in the late 1980s found no evidence at all of any link between the lunar cycle and human behaviour. The moon's influence on us might remain the stuff of legend, but the confusion it sows among wild animals is very real indeed.
Steve Portugal, Reader in Animal Biology and Physiology, Royal Holloway.
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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How New York's largest hospital system is predicting COVID-19 spikes
Northwell Health is using insights from website traffic to forecast COVID-19 hospitalizations two weeks in the future.
- The machine-learning algorithm works by analyzing the online behavior of visitors to the Northwell Health website and comparing that data to future COVID-19 hospitalizations.
- The tool, which uses anonymized data, has so far predicted hospitalizations with an accuracy rate of 80 percent.
- Machine-learning tools are helping health-care professionals worldwide better constrain and treat COVID-19.
The value of forecasting
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTA0Njk2OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyMzM2NDQzOH0.rid9regiDaKczCCKBsu7wrHkNQ64Vz_XcOEZIzAhzgM/img.jpg?width=980" id="2bb93" class="rm-shortcode" data-rm-shortcode-id="31345afbdf2bd408fd3e9f31520c445a" data-rm-shortcode-name="rebelmouse-image" data-width="1546" data-height="1056" />Northwell emergency departments use the dashboard to monitor in real time.
Credit: Northwell Health
<p>One unique benefit of forecasting COVID-19 hospitalizations is that it allows health systems to better prepare, manage and allocate resources. For example, if the tool forecasted a surge in COVID-19 hospitalizations in two weeks, Northwell Health could begin:</p><ul><li>Making space for an influx of patients</li><li>Moving personal protective equipment to where it's most needed</li><li>Strategically allocating staff during the predicted surge</li><li>Increasing the number of tests offered to asymptomatic patients</li></ul><p>The health-care field is increasingly using machine learning. It's already helping doctors develop <a href="https://care.diabetesjournals.org/content/early/2020/06/09/dc19-1870" target="_blank">personalized care plans for diabetes patients</a>, improving cancer screening techniques, and enabling mental health professionals to better predict which patients are at <a href="https://healthitanalytics.com/news/ehr-data-fuels-accurate-predictive-analytics-for-suicide-risk" target="_blank" rel="noopener noreferrer">elevated risk of suicide</a>, to name a few applications.</p><p>Health systems around the world have already begun exploring how <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7315944/" target="_blank" rel="noopener noreferrer">machine learning can help battle the pandemic</a>, including better COVID-19 screening, diagnosis, contact tracing, and drug and vaccine development.</p><p>Cruzen said these kinds of tools represent a shift in how health systems can tackle a wide variety of problems.</p><p>"Health care has always used the past to predict the future, but not in this mathematical way," Cruzen said. "I think [Northwell Health's new predictive tool] really is a great first example of how we should be attacking a lot of things as we go forward."</p>Making machine-learning tools openly accessible
<p>Northwell Health has made its predictive tool <a href="https://github.com/northwell-health/covid-web-data-predictor" target="_blank">available for free</a> to any health system that wishes to utilize it.</p><p>"COVID is everybody's problem, and I think developing tools that can be used to help others is sort of why people go into health care," Dr. Cruzen said. "It was really consistent with our mission."</p><p>Open collaboration is something the world's governments and health systems should be striving for during the pandemic, said Michael Dowling, Northwell Health's president and CEO.</p><p>"Whenever you develop anything and somebody else gets it, they improve it and they continue to make it better," Dowling said. "As a country, we lack data. I believe very, very strongly that we should have been and should be now working with other countries, including China, including the European Union, including England and others to figure out how to develop a health surveillance system so you can anticipate way in advance when these things are going to occur."</p><p>In all, Northwell Health has treated more than 112,000 COVID patients. During the pandemic, Dowling said he's seen an outpouring of goodwill, collaboration, and sacrifice from the community and the tens of thousands of staff who work across Northwell.</p><p>"COVID has changed our perspective on everything—and not just those of us in health care, because it has disrupted everybody's life," Dowling said. "It has demonstrated the value of community, how we help one another."</p>3,000-pound Triceratops skull unearthed in South Dakota
"You dream about these kinds of moments when you're a kid," said lead paleontologist David Schmidt.
Excavation of a triceratops skull in South Dakota.
- The triceratops skull was first discovered in 2019, but was excavated over the summer of 2020.
- It was discovered in the South Dakota Badlands, an area where the Triceratops roamed some 66 million years ago.
- Studying dinosaurs helps scientists better understand the evolution of all life on Earth.
Credit: David Schmidt / Westminster College
<p style="margin-left: 20px;">"We had to be really careful," Schmidt told St. Louis Public Radio. "We couldn't disturb anything at all, because at that point, it was under law enforcement investigation. They were telling us, 'Don't even make footprints,' and I was thinking, 'How are we supposed to do that?'"</p><p>Another difficulty was the mammoth size of the skull: about 7 feet long and more than 3,000 pounds. (For context, the largest triceratops skull ever unearthed was about <a href="https://www.tandfonline.com/doi/abs/10.1080/02724634.2010.483632" target="_blank">8.2 feet long</a>.) The skull of Schmidt's dinosaur was likely a <em>Triceratops prorsus, </em>one of two species of triceratops that roamed what's now North America about 66 million years ago.</p>Credit: David Schmidt / Westminster College
<p>The triceratops was an herbivore, but it was also a favorite meal of the T<em>yrannosaurus rex</em>. That probably explains why the Dakotas contain many scattered triceratops bone fragments, and, less commonly, complete bones and skulls. In summer 2019, for example, a separate team on a dig in North Dakota made <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">headlines</a> after unearthing a complete triceratops skull that measured five feet in length.</p><p>Michael Kjelland, a biology professor who participated in that excavation, said digging up the dinosaur was like completing a "multi-piece, 3-D jigsaw puzzle" that required "engineering that rivaled SpaceX," he jokingly told the <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">New York Times</a>.</p>Morrison Formation in Colorado
James St. John via Flickr
Triceratops illustration
Credit: Nobu Tamura/Wikimedia Commons |
What can Avicenna teach us about the mind-body problem?
The Persian polymath and philosopher of the Islamic Golden Age teaches us about self-awareness.
The incredible physics behind quantum computing
Can computers do calculations in multiple universes? Scientists are working on it. Step into the world of quantum computing.
- While today's computers—referred to as classical computers—continue to become more and more powerful, there is a ceiling to their advancement due to the physical limits of the materials used to make them. Quantum computing allows physicists and researchers to exponentially increase computation power, harnessing potential parallel realities to do so.
- Quantum computer chips are astoundingly small, about the size of a fingernail. Scientists have to not only build the computer itself but also the ultra-protected environment in which they operate. Total isolation is required to eliminate vibrations and other external influences on synchronized atoms; if the atoms become 'decoherent' the quantum computer cannot function.
- "You need to create a very quiet, clean, cold environment for these chips to work in," says quantum computing expert Vern Brownell. The coldest temperature possible in physics is -273.15 degrees C. The rooms required for quantum computing are -273.14 degrees C, which is 150 times colder than outer space. It is complex and mind-boggling work, but the potential for computation that harnesses the power of parallel universes is worth the chase.
The scent of sickness: 5 questions answered about using dogs – and mice and ferrets – to detect disease
Could medical detection animals smell coronavirus?
