This week, freshly analyzed Neanderthal remains suggest our extinct relatives were caring and compassionate, researchers spotted the world’s largest land mammal migration ever recorded, and a robot with a face made out of lab-grown human skin became everyone’s new nightmare. Finally, we explore how some physicists once believed the explosive Tunguska event was actually caused by a black hole passing through the Earth.Subscribe to the IFLScience newsletter for all the biggest science news delivered straight to your inbox every Wednesday and Saturday.A 44,000-Year-Old Wolf Frozen In Permafrost May Still Contain Living BacteriaA prehistoric wolf that’s been frozen like a popsicle for over 44,000 years has undergone a post-mortem in Russia, set to reveal all kinds of insights into its life as an apex predator in the Ice Age. Read the full story here.Neanderthal Child With Down Syndrome Highlights Altruism Among Ancient HumansResearchers in Spain have discovered the remains of a Neanderthal child displaying a number of traits that are consistent with Down syndrome. However, unlike other prehistoric individuals with the condition, the youngster didn’t die as a baby, indicating that both the child and its mother received ongoing care and support from the rest of their ancient tribe. Read the full story here.Six Million Animals Make Moves In The World’s Largest Land Mammal MigrationAround 6 million antelope have been recorded on a trek across East Africa, marking the world’s largest land mammal migration ever recorded. Read the full story here.Watch This Uncanny Robot Face Grin And Frown Thanks To Self-Healing, Lab-Grown Human SkinThis grinning pink blob might populate your nightmares for the next week or two (sorry about that), but if you can see past the all-too-realistic eyes, you’ll find a very impressive feat of engineering. Scientists in Japan have figured out a way to attach lab-grown human skin tissue to the faces of complex humanoid robots. Read the full story here.Family Sues NASA In Unprecedented Case After Piece Of ISS Smashes Into Their HouseA family in Florida has launched a lawsuit against NASA, seeking compensation after a piece of space junk fell from the sky and crashed through the roof of their house. Fortunately, no one was injured in the incident, although the family’s lawyer says the ramifications of this case go far beyond mere damage reparation and could set a precedent for how future claims of this sort are resolved. Read the full story here.TWIS is published weekly on our Linkedin page, join us there for even more content.Feature of the week:Physicists Once Proposed The Tunguska Event Was Caused By A Black Hole Passing Through EarthEvery year on June 30, Earth celebrates Asteroid Day to mark the date of Earth’s largest asteroid impact in recorded history and raise public awareness of asteroid impact hazards and the crisis communication plans should one head our way. Now we know the Tunguska event of 1908, which flattened over 2,000 km2 of forest in Siberia, was likely an airburst from an asteroid, but physicists once proposed it was a primordial black hole passing through Earth. Read the full story here.More content:Have you seen our e-magazine, CURIOUS? It’s about to turn 2! Issue 24 July is out on June 30, and Issue 23 June 2024 is available now. Check it out for exclusive interviews, book excerpts, long reads, and more.PLUS, the first episode of season 4 of IFLScience's The Big Questions Podcast is out now. 

The motion of celestial bodies has been studied and interpreted for tens of thousands of years. Understanding how the Moon and Sun move helped our ancestors thrive across the changing seasons. Expanding that to the planets gave us an idea of our place in the universe. And the advent of the astronomy of precision several centuries ago, brought to light that we are a tiny fish in a very big pond. But how do astronomers work out where things are with respect to us?There are different methods depending on when and what we are trying to map. And we are trying to map a lot of things in the universe. Some to keep our planet safe, some to understand our galaxy and its formation, and some to answer the most profound questions of cosmology.Know Your EnemyCelestial mechanics is complicated. There is no exact solution for the motion of three bodies in a gravitational field (the infamous three-body problem). So imagine when you have thousands of them, like in the Solar System. The way we do that is by measuring their positions over and over again.For the planets and moons, we do not have to do this constantly; we know enough about them to know where they will be for quite a long time. But when it comes to smaller bodies such as asteroids, it is important to understand their precise orbits. This is doubly important for near-Earth objects, those asteroids and comets that come very close to our planet – because they might hit us.These (relatively) small space rocks tend to be very dark. This size and color combination is not great for finding them, but this has not deterred astronomers. Using radio, infrared, and optical telescopes, over the last 25 years, 90 percent of planet-killer (larger than 1 kilometer) asteroids have been discovered.But it is not just about finding them. Repeating observations is important because it allows us to understand and refine the orbits of those bodies, and work out where they have been and where they are going to be. An exciting recent development in this area is the use of radar technology, which allows for a greater precision of the orbital parameters.Our Place Among The StarsRadar would work at most to the orbit of Saturn – but we want to know our place in the Milky Way. The first approach is to work out the distance of stars using the parallax method, bringing some trigonometry to astronomy. Trigonometry is the study of the function of angles. You have your sine, cosine, and tangent.This comes in useful in astronomy when you realize that you can create nice little triangles by working out how a star changes its apparent position in the sky as our planet moves around the Sun. The angles in question are very small, but with precise enough measurements, we can measure the distance of so many stars.And no instrument is more precise for this job than the Gaia spacecraft. This European Space Agency mission has created the most precise map of the Milky Way, working out the position and motion of over a billion stars, but also exoplanets, comets, and asteroids in the Solar System, and even a few black holes.This is not a photograph of the Milky Way, but the map reconstructed using data collected by the Gaia spacecraft. It looks like a photo because it is that good.Image credit: ESA/GaiaThe Shape Of The UniverseBut what about the wider cosmos? For a long time, we were only aware of our own galaxy. We had no way to measure things further afield (the parallax method is only as good as our precision). It was thanks to astronomer Henrietta Swan Leavitt that suddenly the universe was opened up to us. Her work shows that certain stars called Cepheid variables have a specific relationship between their period of variability and their intrinsic luminosity.If you know how luminous an object is and you measure the apparent brightness here after the light has traveled such a long distance, you can work out that distance. This is the principle of the standard candles. By measuring the period of Cepheid variables, there was finally a way to measure extragalactic distances. Not that astronomers knew there was something out there until Edwin Hubble found Cepheid variables in several “nebulae”, including Andromeda, and realized that they couldn’t be in the Milky Way. Those stars were in other galaxies.      But Hubble made another important discovery while studying these newly found galaxies, about a century ago. Almost all of them are moving away from us. It was the first evidence that the universe is expanding. We know that they are moving away because we can measure their redshift. This phenomenon is similar to a Doppler shift, something we often experience on roads. If an ambulance is approaching with its siren on its pitch will be higher and once it passes and moves away from us its pitch will get lower. The siren is not changing, but the sound waves are compressed as it moves towards us and stretched when it moves away.If you move fast enough, the same thing happens with light. Things moving towards us get bluer (their light waves are compressed) and away from us get redder. Redshift is not a true Doppler shift, however, because it is not the motion of the galaxies causing it, but the expansion of the universe.Both the use of standard candles and redshift help us build a 3D picture of the universe, and that is where we hope to find answers to the biggest open questions in cosmology: what is dark matter and dark energy? These two components make up 95 percent of all matter-energy content of the universe. The rest is the regular matter that makes us.        Galaxies are not randomly distributed across space; they are organized in a structure called the cosmic web, which is shaped by all forms of matter and energy. Understanding what it is like precisely – such as with upcoming surveys, like the one planned by the Vera Rubin Observatory – will provide important insights into the mystery and hopefully, solutions.Since antiquity, we have used the heavens to navigate our planet and map our way from here to there. It is only natural then that our map-making obsession has stretched from our pale blue dot to the farthest galaxies we have ever seen.

Have you ever heard of Palynomorphs, “microfossils” that are abundant pretty much everywhere? They’re microscopic fossils that appear in sedimentary rocks across the world and are invaluable for geologists and paleontologists researching the planet’s evolutionary history. However, their tiny size and sheer numbers can be a challenge to work with, so researchers have now created a new machine learning technique to make this otherwise arduous task more manageable.Palynomorphs really are small; they can range from 5 to 500 micrometres in size. If you consider the diameter of a human hair measure between 17 to 181 micrometres, then you get a sense for just how small they can be. Even grains of pollen tend to be larger than the smallest  Palynomorphs.These tiny fragments are made of compounds that are extremely resistant to most forms of decay, as they are often made up of sporopollenin, dinosporin, or similar compounds. They were formed at any point between a couple of million years ago to over 500 million years ago. As such, they are valuable for researchers looking to age a rock layer or reconstruct a long-lost environment – such as whether the layer formed underwater or was a terrestrial feature.Analysis of this variations tell us a lot about how the Earth has changed and can also offer insights into past climate conditions and geological events.Previously, scientists would spend tedious hours manually classifying these microfossils by staring into microscopes where they may see billions of samples across multiple slides. It is a painstaking and frustrating process, but new advances in AI assisted techniques may make this significantly easier.Researcher led by a team from the University of Tromsø, Norway, has introduced a two-stage AI-driven system that detects and classifies microfossils from microscope images.“We propose an automatic pipeline for microfossil extraction and classification from raw microscope pictures. The method is fast and efficient and does not require intensive computing power”, the team wrote.“We show that our approach improves the state-of-the-art for fossil extraction. The identification of individual species with machine learning is new and promising.”The team achieved this in stages. Firstly, they used a pre-trained object detection model - YOLOv5 – to examine, identify and extract individual Palynomorphs from slide images. This process creates bounding boxes that appear around each microfossil, saving dozens of hours of work.The image on the left shows the results of the machine learning method introduced in this research. It is more precise than the one on the right, which was created with the pipeline of standard image processing methods.Image credit: Martinsen et al. 2024.Then, in the second stage, the team used a self-supervised learning system (SSL), which is a relatively new learning paradigm that is increasingly popular. The technique can essentially be trained to extract specific features from the samples it processes. It relies on self-supervised models to generate implicit labels from unstructured data.Within this study, the team compared two SSL frameworks - SimCLR and DINO – both of which were found to be invaluable means for speeding up the classification process.“This work shows that there is great potential in utilizing AI in this field,” Iver Martinsen, first and co-corresponding author of the study said in a statement. “By using AI to automatically detect and recognize fossils, geologists might have a tool that can help them better utilize the enormous amount of information that wellbore samples provide”.The team used the AI to detect Palynomorphs using data obtained by the Norwegian Offshore Directorate, which came from the Norwegian continental shelf. In order to test its accuracy, the team then tested the model by classifying several hundred previously labels fossils from the same well.“We are very happy with our results. Our model exceeds previous benchmarks available out there. We hope that the present work will be beneficial for geologists both in industry and academia,” adds Martinsen.The paper is published in Artificial Intelligence in Geosciences.

Neanderthals, the closest cousins of modern humans, lived in parts of Europe and Asia until their extinction some 30,000 years ago.Genetic studies are revealing ever more about the links between modern humans and these long-gone relatives – most recently that a rush of interbreeding between our species occurred in a relatively short burst of time around 47,000 years ago. But one mystery still remains.The Homo sapiens genome today contains a little bit of Neanderthal DNA. These genetic traces come from almost every part of the Neanderthal genome – except the Y sex chromosome, which is responsible for making males.So what happened to the Neanderthal Y chromosome? It could have been lost by accident, or because of mating patterns or inferior function. However, the answer may lie in a century-old theory about the health of interspecies hybrids.Neanderthal sex, genes and chromosomesNeanderthals and modern humans went their separate ways somewhere between 550,000 and 765,000 years ago in Africa, when Neanderthals wandered off into Europe but our ancestors stayed put. They would not meet again until H. sapiens migrated into Europe and Asia between 40,000 and 50,000 years ago.Scientists have recovered copies of the full male and female Neanderthal genomes, thanks to DNA from well-preserved bones and teeth of Neanderthal individuals in Europe and Asia. Unsurprisingly, the Neanderthal genome was very similar to ours, containing about 20,000 genes bundled into 23 chromosomes.Like us, they had two copies of 22 of those chromosomes (one from each parent), and also a pair of sex chromosomes. Females had two X chromosomes, while males had one X and one Y.Y chromosomes are hard to sequence because they contain a lot of repetitive “junk” DNA, so the Neanderthal Y genome has only been partially sequenced. However, the large chunk that has been sequenced contains versions of several of the same genes that are in the modern human Y chromosome.In modern humans, a Y chromosome gene called SRY kickstarts the process of an XY embryo developing into a male. The SRY gene plays this role in all apes, so we assume it did for Neanderthals as well – even though we haven’t found the Neanderthal SRY gene itself.Interspecies mating left us with Neanderthal genesThere are lots of little giveaways that mark a DNA sequence as coming from a Neanderthal or a H. sapiens. So we can look for bits of Neanderthal DNA sequence in the genomes of modern humans.The genomes of all human lineages originating in Europe contain about 2% Neanderthal DNA sequences. Lineages from Asia and India contain even more, while lineages restricted to Africa have none. Some ancient Homo sapiens genomes contained even more – 6% or so – so it looks like the Neanderthal genes are gradually fading out.Most of this Neanderthal DNA arrived in a 7,000-year period about 47,000 years ago, after modern humans came out of Africa into Europe, and before Neanderthals became extinct about 30,000 years ago. During this time there must have been many pairings between Neanderthals and humans.At least half of the whole Neanderthal genome can be pieced together from fragments found in the genomes of different contemporary humans. We have our Neanderthal ancestors to thank for traits including red hair, arthritis and resistance to some diseases.There is one glaring exception. No contemporary humans have been found to harbour any part of the Neanderthal Y chromosome.What happened to the Neanderthal Y chromosome?Was it just bad luck that the Neanderthal Y chromosome got lost? Was it not very good at its job of making males? Did Neanderthal women, but not men, indulge in interspecies mating? Or was there something toxic about the Neanderthal Y so it wouldn’t work with human genes?A Y chromosome comes to the end of the line if its bearers have no sons, so it may simply have been lost over thousands of generations.Or maybe the Neanderthal Y was never present in interspecies matings. Perhaps it was always modern human men who fell in love with (or traded, seized or raped) Neanderthal women? Sons born to these women would all have the H. sapiens form of the Y chromosome. However, it’s hard to reconcile this idea with the finding that there is no trace of Neanderthal mitochondrial DNA (which is limited to the female line) in modern humans.Or perhaps the Neanderthal Y chromosome was just not as good at is job as its H. sapiens rival. Neanderthal populations were always small, so harmful mutations would have been more likely to accumulate.We know that Y chromosomes with a particularly useful gene (for instance for more or better or faster sperm) rapidly replace other Y chromosomes in a population (called the hitchhiker effect).We also know the Y chromosome is degrading overall in humans. It is even possible that SRY was lost from the Neanderthal Y, and that Neanderthals were in the disruptive process of evolving a new sex-determining gene, like some rodents have.Was the Neanderthal Y chromosome toxic in hybrid boys?Another possibility is that the Neanderthal Y chromosome won’t work with genes on other chromosomes from modern humans.The missing Neanderthal Y may then be explained by “Haldane’s rule”. In the 1920s, British biologist J.B.S. Haldane noted that, in hybrids between species, if one sex is infertile, rare or unhealthy, it is always the sex with unlike sex chromosomes.In mammals and other animals where females have XX chromosomes and males have XY, it is disproportionately male hybrids that are unfit or infertile. In birds, butterflies and other animals where males have ZZ chromosomes and females have ZW, it is the females.Many crosses between different species of mice show this pattern, as do feline crosses. For example, in lion–tiger crosses (ligers and tigons), females are fertile but males are sterile.We still lack a good explanation of Haldane’s rule. It is one of the enduring mysteries of classic genetics.But it seems reasonable that the Y chromosome from one species has evolved to work with genes from the other chromosomes of its own species, and might not work with genes from a related species that contain even small changes.We know that genes on the Y evolve much faster than genes on other chromosomes, and several have functions in making sperm, which may explain the infertility of male hybrids.So this might explain why the Neanderthal Y got lost. It also raises the possibility that it was the fault of the Y chromosome, in imposing a reproductive barrier, that Neanderthals and humans became separate species in the first place. Jenny Graves, Distinguished Professor of Genetics and Vice Chancellor's Fellow, La Trobe UniversityThis article is republished from The Conversation under a Creative Commons license. Read the original article.

Ultra-processed foods are so harmful to health that they should be sold carrying tobacco-style warnings, according to the epidemiologist who coined the term.“UPFs [Ultra-processed foods] are increasing their share in and domination of global diets, despite the risk they represent to health in terms of increasing the risk of multiple chronic diseases,” Carlos Monteiro, a professor of Nutrition and Public Health at the University of São Paulo, told the Guardian.“[They] are displacing healthier, less processed foods all over the world, and also causing a deterioration in diet quality due to their several harmful attributes,” he said. “Together, these foods are driving the pandemic of obesity and other diet-related chronic diseases, such as diabetes.”Speaking at the International Congress on Obesity 2024 this week, Monteiro warned that ultra-processed foods, or UPFs, are now so prevalent, and so impactful upon human health, that their sale and consumption should be heavily restricted, with “front-of-pack warnings […] similar to those used for cigarette packs” introduced for offending foodstuffs.On the face of it, the idea seems logical – albeit a bit drastic. UPFs really have overtaken the diets of many in the West, with more than half of the average diet in the US and UK comprising this type of food. They increase the average calorific intake of those who eat them – even when compared to unprocessed diets which have been matched for salt, fat, and sugar content – and have been linked to dozens of harmful effects on the body, including an increased risk of heart disease, various cancers, diabetes, and can even reduce your mental health. So Monteiro’s argument that UPFs should be treated as a public health hazard, similar to tobacco products, is not without merit. “Both tobacco and UPFs cause numerous serious illnesses and premature mortality; both are produced by transnational corporations that invest the enormous profits they obtain with their attractive/addictive products in aggressive marketing strategies, and in lobbying against regulation; and both are pathogenic (dangerous) by design,” Monteiro pointed out. “Reformulation is not a solution.”But some have called the banning or restriction of UPFs overly simplistic. For one thing, the kinds of food that would be affected by such a move might surprise you: while it sounds dramatic, the term “ultra-processed” really only describes food which comprise multiple ingredients with additives – so, yes, the fast-food hamburger meal that you’re thinking of counts, but so does baby formula, fruit yogurt, and even store-bought bread.The consumption of UPFs is also highly skewed towards those in poverty. “We already know that consumption of ultra-processed foods and snacks high sugar are associated with rising rates of obesity. We also know that there are socioeconomic disparities in health and diet,” noted Paul Coleman, Honorary Senior Research Fellow at the Centre for Food Policy, City, University of London, and Senior Public Health Registrar at Leeds Teaching Hospital NHS Trust, back in November 2023. For these parents, more labeling would not be useful: “they know [UPFs] are bad for their child’s health,” Coleman said – but they have “little option but to buy these unhealthy options […] The low-cost and long-shelf of unhealthy snacks make them the most logical option, despite parents wanting to make healthy purchases.”Equally, while Monteiro draws a comparison with tobacco products, other scientists reject the analogy: “There is no such thing as a safe cigarette, even second-hand, so banning them is relatively straightforward in that the health case is very clear,” Hilda Mulrooney, a reader in nutrition and health at London Metropolitan University, told The Guardian. “However, we need a range of nutrients including fat, sugar and salt, and they have multiple functions in foods – structural, shelf-life – not just taste and flavor and hedonic properties,” she explained. “It is not as easy to reformulate some classes of foods to reduce them and they are not the same as tobacco because we need food – just not in the quantities most of us are consuming.”The International Congress on Obesity 2024 is running from 26-29 June 2024 in São Paulo, Brazil.

Thousands of people take the Tube from the north side of London to the south, or pop across the English Channel via the Channel Tunnel every day, but they’re only able to do so thanks to one pretty important feature – underwater tunnels. But how is such an impressive feat of engineering built?The tunneling shieldUnderwater tunnels had people stumped until French-British engineer Marc Isambard Brunel took inspiration from nature back in 1818. After watching how a shipworm’s shell plates allowed it to bore through wood, Brunel took that principle and scaled it up into the tunneling shield.In this case, it was a giant, rectangular cast iron casing with shutter openings on its wall, which were opened one at a time so that miners could dig away the soft earth outside. The shield was then pushed forward using screw jacks and the process repeated, with the protective “shell” of the tunnel built out of bricks in the freshly carved area behind.This led to the first-ever underwater tunnel being built under the River Thames in London, completed in 1842. Later tunnels under the Thames improved upon this method by pressurizing the air in front of the shield to try and stop flooding during construction. Tunneling shields are still used today, but are instead cylindrical and tend to be made out of steel, which is also used to make the tunnel’s support rings. Modern variations also make use of hydraulic jacks to push the shield forward, but when it’s not moving the area in front of the shield can be accessed via a door. To protect those who go out to work there, shields also feature a protective hood.Tunnel boring machinesOf course, digging through soft earth is one thing – boring through underwater rock is another thing entirely. That’s where modern technology has changed the game, in the form of tunnel boring machines (TBMs), which were used in the construction of the Channel Tunnel.TMBs have a function similar to the tunneling shield, but in this case, a mechanical spinning cutting head, rather than human force, is used to dig through the rock in front. It does this by exerting stress on the rock, which causes it to fracture. And rather than people having to lug the debris out of the way, the fractured rock is taken back on a conveyor belt.A total of 11 TMBs were used to dig out the three 56.3-kilometer (35-mile) long tunnels (yep, there’s more than one), which in their underwater stretches, are found 45 meters (148 feet) below the sea bed.Immersed tube tunnelsWith the previous methods, the tunnel walls are constructed as digging goes, but that’s not the only way to do it. There’s also immersed tube tunneling, a technique developed by American engineer W.J. Wilgus.This method involves making the tunnel elsewhere first, creating multiple prefabricated segments, whilst a trench is dredged from the river or seabed where the tunnel is destined to be. The segments are then floated to the area, and sunk into place, after which the water is emptied from them, and excavated material is placed over the tunnel to bury it and restore the bed.

Some insects have detachable penises, others produce sperm that is 20 times the size of their own body. Others have evolved with special equipment to help them tear rivals off potential mates. Insects can be creepy, promiscuous or murderous – but they are rarely dull.The stag beetle male – Europe’s largest beetle has huge jaws known as antlers designed for prising mating pairs apart. This behaviour is seen in numerous beetles, with horns of various shapes horns that have evolved to lever males off females. The Japanese rhinocerous beetle has a horn resembling a fork. Antlers are also used in battle to wrestle other males over access to females.The Japanese rhinoceros beetle has a sinister looking horn. Mark Brandon/ShutterstockIn many of these species, smaller males don’t stand a chance of winning a fight, so instead have evolved sneaky mating tactics. They wait for males to fight, then slink in and copulate with the female while the males are distracted. Small male dung beetles slip past large males that guard entrances to tunnels containing females, and dig secret passages to find the underground females while the larger males’ backs are turned.Sperm competitionIn addition to the physical contests between males, competition to fertilise an egg also happens between sperm. In the animal kingdom, females are rarely faithful to their mates, so there is probably sperm from a number of males inside a female reproductive tract. Males have evolved several ways to counter this, such as producing large sperm. Fruit fly sperm, is almost 6cm long when uncoiled, around 20 times the size of the fly.But, perhaps the most extraordinary method to win the sperm competition is seen in the odonata (dragonflies and damselflies) who have evolved ornate penises. These come complete with hooks and whips, to dislodge the sperm of rival males and pack the male’s own sperm into the far corners of the female reproductive tract, away from other male penises.And it’s not just the males that have elaborate penises. The female cave insects of Brazil compete for access to males. The insects have sex-reversed genitalia, where the males have an opening and the females have a spiky erectile organ. The female uses her “penis” to suck sperm out of the male, and she can even decide which of two chambers in her body to store the sperm in. It is thought that this behaviour evolved as an adaptation to a limited food supply as the females gain energy from feasting on the seminal fluid acquired during copulation, which can last up to 70 hours.Butterflies only live for a few weeks, so if males are going to father any offspring, they can’t hang around. Except, some do. Many butterflies are sexually mature as soon as they emerge from their chrysalis. So, in some species the males emerge a few days before the females, then sit and wait, copulating with the females as soon as possible.More disturbing behaviour is seen in the bed bug. Males simply pierce a female’s abdomen then inject sperm through the wound into her abdominal cavity. As insects have an open circulatory system without arteries and veins, the sperm can easily migrate from the abdominal cavity to the ovaries for fertilisation.Male bed bugs have a brutal approach to mating. TinoFotografie/ShutterstockSexual cannibalismProbably the most famous of the insect sexual behaviour is that of the praying mantis, where the female bites the head off her partner during or after sex, gaining nutrients for herself and her offspring. This behaviour increases the number of eggs that males fertilise. Recently, scientists found that males also attack females. They don’t eat the females although they sometimes seriously injure them. Males that won fights with females were more likely to go on to mate rather than just get eaten.Chastity beltsMany male insects only get to mate once, even when they aren’t eaten by their partners. For example, male bees ejaculate with such explosive force that it is loud enough for humans to hear. This ensures the sperm is passed to the female, but it results in paralysis of the male, which kills him. So, males need to make the most of their exploits.One way of preventing other males from mating with a female is to produce a copulatory plug – something that will prevent a different male from inserting his sperm inside a female to fertilise her eggs. The European dwarf spider produces a plug by secreting a liquid during copulation that hardens over time. Researchers have found that longer copulations result in larger plugs which are more difficult for other males to remove.In order to ensure that nobody else mates with his female once he is dead, the male orb-web spider has evolved an extreme copulatory plug. He has a detachable penis that remains inside the female once copulation is over. Although it is common for the tip of a spider’s penis to break off inside a female, preventing other males from entering, the orb-web spider’s detachable penis has an additional function as it continues to transfer sperm on its own - for over 20 minutes – increasing mating success.So you see, insects are, in fact, amazing. Louise Gentle, Principal Lecturer in Wildlife Conservation, Nottingham Trent UniversityThis article is republished from The Conversation under a Creative Commons license. Read the original article.

On the face of it, spending any amount of time in a small, 80°C (176°F) room might sound thoroughly unenjoyable – but many people do it willingly on a regular basis. How? Visiting saunas, which are a regular part of life in countries like Finland but have recently shot up in popularity elsewhere too. That might be in part because of their apparent health benefits, but how true are these claims? Do saunas have any health benefits?DementiaRecent years have seen headlines purporting the apparent benefits of saunas for the brain, particularly when it comes to preventing Alzheimer’s disease and other types of dementia. Why? It may well be due to two studies, one from 2016 and the other from 2020, that suggest a link between frequent sauna use and a lower risk of dementia.The earlier study used data that followed over 2,000 healthy Finnish adult males for an average of roughly 20 years, who had to fill out a questionnaire about their typical weekly sauna use, including frequency, duration, and temperature. The second study was similar, but larger; it followed nearly 14,000 Finnish men and women over 39 years and their typical sauna activity in a month. Both studies identified whether or not participants went on to get diagnosed with dementia.In both cases, the studies concluded that frequent sauna use could potentially reduce the risk of developing dementia, even when taking into account other risk factors for the condition. The 2016 study found, for example, that sauna bathing four to seven times a week was associated with a 66 percent reduced risk of Alzheimer's, compared to only having one session per week.Though not going so far as to define exactly how this might work, the researchers suggest it could involve a reduction in blood pressure or the activation of protective heat shock proteins.It all sounds promising, but the two studies should be interpreted with caution. For example, the questionnaire about typical sauna use was only filled out once – people’s habits may well have changed over the years.And unlike clinical trials, where researchers intervene – in this case, they’d be splitting people into groups and getting them to use saunas differently – both studies are observational.This means there was no intervention, and they weren’t carried out with the purpose of proving that sauna use affects dementia risk. That doesn’t mean there isn’t a potential link, but neither study proves it – more research would be needed to do so.Cardiovascular healthThe same group of researchers from the 2016 study on dementia also followed the same group of Finnish males for their cardiovascular (heart and blood vessels) health. In a separate paper on this subject, they found that more frequent use of saunas could be linked to a “considerable decreased risk” of sudden cardiac death, fatal coronary heart disease, and fatal cardiovascular disease.That being said, the problems with the study are the same as before; clinical trials would be required to provide solid evidence of a link and figure out exactly how risk reduction works. The researchers also caution that their findings should be treated with care by people with certain cardiovascular conditions; saunas can reduce blood pressure, which is more than a bit dangerous for people whose blood pressure is already low.Sauna bathing alone might not be the answer anyway – another way of improving cardiovascular health is regular exercise, which a more recent, small study suggests could be beneficial when combined with sauna use.Mental healthOne area that might seem to benefit from getting our sauna on is our mental health, and according to the Global Sauna Survey, which had 482 valid responses, that seems to be the case. For example, 83.5 percent of all those surveyed reported having better sleep after sauna use, and those respondents who reported using saunas between five and 15 times a month had slightly higher wellbeing scores compared to less frequent users.Then again, the most cited motivation for using a sauna was relaxation and stress reduction; the act of simply setting aside that time for that specific purpose may well have helped. Add to that the fact the survey was conducted online in a non-random group of people, and only represented 29 countries – with all apart from Finland, Australia, and the US making up less than five percent of participants each – and the results can’t necessarily be considered reliable or be applied to everyone.Do saunas have any health risks?Even if saunas were found to have health benefits in abundance, using them does still carry some risks. That’s because, well, they’re hot – and getting that bit too hot can be a problem for the body. One of the main risks from the sweltering temperatures is dehydration, thanks to the hefty amount of sweat produced by the body in response to that heat (and before you think it, no, you don't "detox" via sweat - that's what your liver and kidneys are for). If that fluid isn’t replenished, then the body can’t function normally, and you can wind up with headaches, low blood pressure, and tiredness.Some have also expressed concern about the effect of saunas on fertility in males, after a study of 10 healthy males found reduced sperm count and motility after 3 months of two sauna sessions per week. However, it should be noted that a) it’s a small study, so further research is needed to validate it and b) a lower sperm count may not necessarily harm your fertility. How to stay sauna safeRegardless of whether they have health-related superpowers, people clearly still enjoy using saunas – it’s just important to do so safely. The general tips for avoiding the riskier elements of a sauna include:Avoid alcohol – that can increase the risk of dehydrationDon’t stay in for longer than 15-20 minutesTake your time cooling down afterwardsDrink plenty of water after you’re out – around two to four glasses’ worthDon’t use if you’re illAll “explainer” articles are confirmed by fact checkers to be correct at time of publishing. Text, images, and links may be edited, removed, or added to at a later date to keep information current.  The content of this article is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of qualified health providers with questions you may have regarding medical conditions.

The humble mug is one of the most important parts of an office. It’s there to hold your coffee when you need that boost first thing in the morning, to show off your personality with a funky pattern or amusing joke, or to hold on to for warmth when someone else is controlling the aircon. It cares for you – but are you giving it the love and attention it truly deserves? In other words, are you giving it a regular wash?Take a look at Reddit and you’ll soon find that people take a lot of different approaches to cleaning their coffee mugs; some wash it every day, others just give it a quick rinse between uses and some, well, they just like to let all the flavors of every drink they’ve ever had mix together.A survey of over 2000 British adults had similar findings. Those who cleaned their office mugs after every single use were in the majority – at least if they were telling the truth – but there were plenty who went multiple uses without giving it a good scrub and 3 percent who confessed to never washing it at all (although Brits are even worse when it comes to washing towels).While that could be a problem if some delightfully fluffy mold starts to grow, the bacteria that lurk within an unwashed mug aren’t necessarily a problem.“If I went and cultured the average unwashed coffee cup, of course I’m going to find germs,” Dr Jeffrey Starke, an infectious disease specialist, told the Wall Street Journal. “But remember the vast majority came from the person who used the cup.”So what about the germs that don’t come from the mug’s owner? Dr Charles Gerba, a professor of microbiology, environmental sciences, and public health at the University of Arizona, told LifeHacker that “around 90% of most office coffee mugs harbor dangerous germs, and 20% of those carry fecal bacteria."Unless someone in the office is taking inspiration from Andy Samberg’s character’s antics in the “Like A Boss” music video, both Starke and Gerba suggest that any of the nastier bacteria that could be lurking in your mug might actually come from… cleaning it.The sponge in the break room probably has the highest bacteria count of anything in the office,” said Starke, speaking to the Wall Street Journal. That would make a lot of sense – it touches a lot of different stuff, sits there damp, and probably isn’t replaced all that often. As Starke quite accurately concluded: “Most people would call that gross.”With that, it might seem better to leave it unwashed, though plenty of people would also be grossed out by that prospect. In that case, experts recommend making use of paper towels, alongside soap and hot water, to scrub your office mug as well as to dry it. Better still, take it home and pop it in the dishwasher if you have one. As for how often you should do so, some would say after every use – but we won’t tell if you don’t. 

New modeling has shown that low-temperature hydrothermal vents could exist at the bottom of the underground oceans on Jupiter’s moon Europa and Saturn’s moon Enceladus for a very long time. They could warm the oceans and give rise to alien life. On Earth, hydrothermal vents are both a source of energy and heat and one of the possible places for the origin of life. The study was published in the journal Geophysical Research: Planets, reports Space. Although there are both high-temperature and low-temperature hydrothermal vents in the Earth’s oceans, a much larger volume of water passes through the latter. High-temperature hydrothermal vents rely on volcanic activity. Saturn’s moon Enceladus And they can pump energy and heat from the Earth’s hot core. But the icy moons of Jupiter and Saturn do not have hot cores. So scientists created simulations to find out how common low-temperature vents are on Europa and Enceladus. Given the lack of data on the oceans on these satellites, which lie beneath the icy surface, the scientists based their modeling on the water circulation system in the northwest Pacific Ocean. There, cool seawater sinks and flows into the rock at the bottom through extinct volcanic cavities called seamounts. The water passes through the rock, heats up, and rises through another seamount. According to scientists, the water comes out at a higher temperature and has a completely different chemical composition. Jupiter’s moon Europa By applying this water circulation model to Europa and Enceladus, scientists modified properties such as gravity, temperature, seafloor composition, and water circulation depth to better match the potential conditions in the oceans of these moons. Modeling has shown that low-temperature hydrothermal vents can exist at the bottom of underground oceans under a wide range of conditions. At the same time, lower gravity ensures greater heating of the water coming out of the sources. Scientists believe that conditions on the satellites allow these sources to exist for billions of years. And this is enough for alien life to arise there. Therefore, theoretically, life could exist in hydrothermal vents on Europa and Enceladus. Now all that remains is to explore their oceans and discover it, if it really is there. The post It turned out where alien life is hiding on the satellites of Jupiter and Saturn appeared first on Anomalien.com.