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There is something unique about the color purple: Our brain makes it up. So you might just call purple a pigment of our imagination. It’s also a fascinating example of how the brain creates something beautiful when faced with a systems error. To understand where purple comes from, we need to know how our eyes and brain work together to perceive color. And that all begins with light. Light is another term for electromagnetic radiation. Most comes from the sun and travels to Earth in waves. There are many different types of light, which scientists group based on the lengths...

Have you ever looked at a bath and thought “Nah, not today!”? Well, you are not alone, as bathing has been a very up-and-down trend across history and from culture to culture. Ancient Rome’s public baths could be a grand affair, with all classes of Roman society taking frequent hot soaks. This contrasts with people in early-modern Europe who avoided clean water altogether for fear that it caused illnesses. Then there are more recent times, when having baths and showers in the house is basically considered essential. These different trends raise the important question: what happens when humans decide not...

In a nutshell * Scientists have developed a plant-based cheese using a specific pea protein and oil blend (25% coconut oil, 75% sunflower oil) that matches the texture and melting properties of dairy cheese while containing less saturated fat. * The breakthrough challenges the common belief that high saturated fat content is necessary for proper cheese texture, as the new formulation achieved similar firmness (80 Newtons) to versions made with 100% coconut oil. * The research demonstrates that carefully selected plant proteins can create healthier cheese alternatives without sacrificing the stretchy, melty qualities consumers expect, potentially revolutionizing the plant-based dairy...

UC Davis graduate student Jeffrey Groh has discovered how walnut trees are able to produce flowers of different sexes at different times in the same season. The genetic mechanism is similar to sex determination in many animals. Pictured, Groh with a California black walnut tree on the UC Davis campus. Credit: Sasha Bakhter, College of Biological Sciences ============================================================================ Biologists at UC Davis have uncovered a fascinating genetic mechanism in walnut trees, allowing them to alternate between male and female flowers each season—a trait stable for 40 million years. This discovery not only sheds light on plant reproduction but also parallels...

TFAs, harmful fats linked to heart disease, can form during home cooking with sulfur-rich vegetables like garlic and onions at high temperatures. A Japanese study found this effect is minor under normal conditions but emphasized awareness of TFA risks. A new study reveals that garlic and onions contain compounds that can convert into trans fats when exposed to high cooking temperatures. Trans-fatty acids (TFAs) are a significant contributor to cardiovascular diseases. These harmful fats can build up on the walls of arteries, narrowing them and increasing the risk of heart attacks. The World Health Organization (WHO) estimates that TFAs are...

What if a centuries-old Amazonian brew held the key to better mental health and well-being? Ayahuasca, a psychoactive tea traditionally used in spiritual ceremonies, is once again making headlines after the most extensive study of its kind reveals promising associations between its use and improved mental health outcomes. “Ayahuasca has been used for centuries by Indigenous communities for healing and spiritual purposes, but despite its growing global popularity, its effects on mental health in contemporary settings are not well understood,” study co-author and adjunct associate professor at Swinburne University in Australia, Daniel Perkins, told PsyPost. “With more people around the...

Remember, 100° in the USA means you're hot; 100° anywhere else means it's the apocalypse. Image credit: Tomas Ragina/Shutterstock.com Oh, America. You do so confuse the rest of the world, with your “pounds per square inch” and “cups”, instead of sensible measurements like Pascals and liters. And part and parcel of that is your stubborn refusal to drop Fahrenheit in favor of Celsius. Of course, we admit that Fahrenheit does have some advantages. But are they really enough to justify its use in the 21st century? Let’s find out. The case for Fahrenheit We’ll say it: Fahrenheit gets a bad...

The distant galaxy has all the structure of a modern spiral galaxy (the object next to it is another galaxy in the foreground). Image credit: Xiao et al., arXiv 2024 (CC BY 4.0) It has been just over three years since JWST was launched into space and in that time, the telescope has dramatically expanded our understanding of the distant universe. Among the important findings is the discovery of very young galaxies that already looked like their more senior counterparts in the local universe, and a recent study has shown a spiral galaxy that already had everything modern ones do...

The human ability to walk and run efficiently on two feet arose around 2 million years ago with our Homo erectus ancestors. But our earlier relatives, the australopithecines, were also bipedal around 4 million years ago. Given the long arms and different body proportions of species like Australopithecus afarensis, though, researchers have assumed that australopithecines were less capable of walking on two legs than modern humans. In a study published online Dec. 18 in the journal Current Biology, a team of researchers modeled the skeletal and muscular anatomy of Lucy to determine her maximum running speed, the energetic costs associated...

Every time you reach for a coke, you could be losing 12 minutes of your life, scientists have claimed. The worrying statistics were found in a study conducted by the University of Michigan which delved into just how much time certain processed foods take from your life. Ultra-processed foods – which contain ingredients such as artificial colours and flavours, preservatives and emulsifiers – can be dangerous if not eaten in moderation. And some favourites could end up costing you minutes of your life. A hot dog could shave off 36 minutes – and if you drink it with a coke,...

Quantum teleportation, once confined to the pages of science fiction, is steadily becoming a tangible scientific achievement. Advances in quantum mechanics over the last decade have transformed teleportation from a theoretical concept into an experimental reality. These breakthroughs have revealed innovative methods for transmitting information instantaneously over vast distances, offering transformative possibilities for computing, communication, and cryptography. Scientists are now closer than ever to bridging the gap between imagination and reality in this cutting-edge field.

A controversial 2020 study that claimed the malaria drug hydroxychloroquine showed promise for treating COVID-19 has been retracted, after sparking widespread criticism from scientists ever since its publication. The study was originally published online in the International Journal of Antimicrobial Agents on March 20, 2020. With a small sample size of just 36 total participants, the trial had involved treating 20 COVID-19 patients with 600 milligrams of hydroxychloroquine, a drug best known as an antimalarial. Some of the patients were also given the antibiotic azithromycin. Based on the results, the authors concluded that hydroxychloroquine was “significantly associated with viral load...

Hping to keep tabs on the magnetic north's wandering ways, the World Magnetic Model 2025 has been released this week, revealing the latest official predicted placement of Earth's magnetic fields. This version will remain valid until late 2029, during which time we can expect to see the magnetic north pole slowly edge further toward Russia. The new version is of timely importance too as the magnetic north pole’s movement seems to be accelerating. Since the 1830s, the north magnetic pole of Earth has relocated some 2,250 kilometers (1,400 miles) across the upper stretches of the Northern Hemisphere from Canada towards...

A new study led by a University of Arizona researcher is one step closer to an answer on how Indigenous people in the Americas interacted with early dogs and wolves.The study, published Wednesday in the journal Science Advances and based on archaeological remains in Alaska, shows that people and the ancestors of today's dogs began forming close relationships as early as 12,000 years ago – about 2,000 years earlier than previously recorded in the Americas..."People like me who are interested in the peopling of the Americas are very interested in knowing if those first Americans came with dogs," Lanoë added....

The object entered our orbit in September. Image credit: buradaki/Shutterstock.com Earlier this year, the number of moons orbiting Earth temporarily doubled, admittedly from the low starting point of "one". Taking a closer look at the new mini-moon, astronomers have learned more about its origin. On August 7, astronomers discovered a new near-Earth object, dubbed 2024 PT5. Analyzing the object, around 10 meters (33 feet) in diameter, astronomers from the Complutense University of Madrid, Carlos de la Fuente Marcos and Raúl de la Fuente Marcos, found that it was on a pleasing trajectory. For 56.6 days, the asteroid would become captured...

A stuffed Tasmanian tiger (Thylacinus cynocephalus) at the Natural History Museum in Berlin, Germany. Image credit: Mazur Travel/Shutterstock.com Scientists claim to have pieced together the most complete genome of a Tasmanian tiger to date – with the help of RNA from a head that’s been preserved in alcohol for over a century. The potential breakthrough is the latest chapter in an effort by Colossal Biosciences and the University of Melbourne’s Thylacine Integrated Genetic Restoration Research (TIGRR) Lab to resurrect the extinct animal, also known as a thylacine. The team estimates that their new genome of the animal is over 99.9...

The crater lies deep beneath the Atlantic Ocean and was formed around 66 million years ago – making it a contemporary of Chicxulub. It is thought that the asteroid hit Earth at around 72,000 kilometers (44,700 miles) per hour. Image credit: muratart/Shutterstock.com Some 66 million years ago, a massive asteroid slammed into Earth. The Chicxulub impactor, as it is called, famously wiped out the non-avian dinosaurs and left a huge crater at the edge of the Yucatán peninsula – but it may not have acted alone. New research has revealed that a second, smaller space rock smashed into our planet...

The unmistakable work of prehistoric humans was found etched into the mammoth's hide. Yuka the mammoth may have been killed by cave lions. Image credit: Zhuravlev Andrey/Shutterstock.com Often hailed as the best-preserved woolly mammoth corpse ever discovered, the body of a young female specimen named Yuka has just yielded a staggering surprise. By analyzing cut marks on the animal's hide, researchers have now determined that the beast was butchered by humans 39,000 years ago, thus providing the earliest evidence for the presence of people in the Arctic. Discovered in 2010 in the extreme north of Siberia, Yuka is thought to...

In a couple of weeks, Earth will have a mini-moon for 56.6 days. Welcome to the neighborhood, 2024 PT5. Image credit: Buradaki/Shutterstock.com An asteroid heading towards Earth is set to have an unusual fate: instead of smashing through our planet’s atmosphere, it’s likely to become trapped in orbit and become a mini-moon. It will be a swift visit, however, and is likely to only remain in Earth's gravitational grasp for two months. The asteroid, named 2024 PT5, was discovered on August 7 and measures around 10 meters (33 feet) in diameter. Two astronomers from the Complutense University of Madrid, Carlos...

The carvings at Göbekli Tepe even show the movements of the constellations. Image credit: Dr Martin Sweatman Acataclysmic comet impact 13,000 years ago may have sparked the rise of civilization, according to the authors of a new study. The event – which many scientists believe never happened – may even be documented at the world-famous site of Göbekli Tepe, forming part of a series of carvings that the researchers say represent the world’s oldest solar calendar. Located in southern Türkiye, Göbekli Tepe is a pre-pottery Neolithic complex that is estimated to be around 12,000 years old. Analyzing an intricately carved...