This ancient predator had two spiny appendages sticking out of its face. This creature Anomalocaris canadensis may have been the freakiest thing to ever haunt the sea. For decades, scientists thought it used those strange limbs to snatch trilobites off the seafloor. The beast could then crush and eat these crunchy snacks. But a new study hints that A. canadensis instead used its spiny limbs to swiftly hunt soft prey. 



Researchers shared their new findings on July 12. The work appeared in Proceedings of the Royal Society B.





A. canadensis means the abnormal shrimp from Canada. It prowled the seas roughly 500 million years ago. Only about as long as a housecat, it still was one of the biggest animals of the Cambrian Period. (The Cambrian ran from about 540 million to 485 million years ago.) That makes A. canadensis one of the earliest top predators.





These sea monsters were like the orcas or great white sharks of their time, says Jakob Vinther. He did not take part in the new study. But he is a paleontologist at the University of Bristol in England. 



Some researchers thought A. canadensis hunted another iconic Cambrian critter the trilobite. Thats because people have unearthed lots of fossils of injured trilobites. This hinted that something had attacked them. A. canadensis became a prime suspect.



But Russell Bicknell wasnt so sure. After all, trilobites have hard, thick exoskeletons. And no one had shown that A. canadensis could crack that armor.



Bicknell is a paleobiologist. He works at the American Museum of Natural History in New York City. He was part of a team that set out to learn if A. canadensis really could have crushed and chowed down on trilobites.



This is a closeup of an A. canadensis fossil. It was found in the Burgess Shale of Canada. The fossil shows the creatures head and curled front appendages.Allison Daley


Pinning softies with its spikes



The researchers compared the ancient creatures bendy appendages to those of modern arthropods. These animals include todays insects, spiders and crustaceans. Bicknells team also built computer models of the limbs on A. canadensis. Using those models, the team tested the limbs toughness, range of motion and best swimming position.



The ancient spiky limbs would have been good at grabbing prey. In that way, A. canadensis may have hunted much like todays whip spiders. But the limbs of A. canadensis probably were too fragile to attack armored prey. Those would have included trilobites.





Plus, A. canadensis would have moved most efficiently when its appendages were stretched out front. (Think of how Superman holds his arms while in flight.)



Together, these results suggest that A. canadensis was best suited for chasing soft creatures swimming through the water. It would have snagged prey in its spiky clutches, Bicknell says. It was going to absolutely pincushion something soft and squishy.

The SouthernTropical Andes, which comprisesareasof Ecuador, Peru, and Bolivia, is one of the world's most biodiverse regions especially when it comes to amphibians. The areais home to about980amphibianspecies, including over half of the 150-knownglass frog species. Now, two new membersof the tiny frogs have joined thisever-growing list.

Thecountdown tothe 2020 Summer Gameshas begun. On July 23, 2021, about 11,000 athletes from 206 countries will gather at the Olympic Stadium in Tokyo, Japan, for the opening ceremony of the Games of the XXXII Olympiad.Here are a few contestantsto keep an eye on at the world's mostprestigious sporting event.

A seriesof deadly tornadoesswept across a large swath of the Midwestern and SoutheasternUS overnight onDecember 10, 2021.TheNational Weather Service (NSW)estimates that the severe storms spawned about50 twisters across eight states Arkansas, Indiana,Kentucky, Missouri, Mississippi, Tennessee, Ohio, and Illinois.

Bacteria can have superpowers. Some flourish in almost any environment. Others can transform toxic materials into harmless sludge. A bacterium called Shewanella oneidensis can do both. But this microbe also has a much rarer superpower: It absorbs and produces electricity. In fact, new research suggests, these bacteria may be able to use energy collected from wind or solar sources to make fuels to run vehicles and more.



I think of these organisms as eating electricity, says Annette Rowe. Shes a microbiologist at the University of Cincinnati in Ohio. Her team has just identified which genes the microbe uses to gobble electricity.



Explainer: Understanding electricity



Electrons are negatively charged particles. A moving stream of them creates an electric current. Scientists already knew that Shewanella can move electrons back and forth across its cell wall. But they didnt know exactly how the microbes controlled their current, Rowe says.





The pathway for getting the electrons in and out of the cell is like a wire, says Rowe. It allows current to flow from the inside to the outside. Reverse the flow, she says, and you can drive electrons into the cell. The cell could then use those electrons to do some other job, such as generate current. Or it could store the energy to use later. Those electrons could later be used to make fuel, for example.



Rowe knew that Shewanellas cellular wire had to be controlled by genes. But which ones?



Buz Barstow was able to help. He is a biological engineer at Cornell University. Its in Ithaca, N.Y. Earlier, he had made a list of nearly 4,000 of this bacteriums genes. That list also included mutations, or changes, in those genes. Rowe tested these mutants to find the genes that made up Shewanella’s cellular “wire.”



Explainer: What are genes?



Within a cell, a gene can deleted. For the new study, Rowe and her colleagues tested groups of bacteria with groups of deleted genes. Their goal: to see which deleted genes allowed the bacteria to pull in electrons. These were likely genes involved in making the cell’s “wire.”



That was no easy task. It was really tricky to look for electron flow and track the electrons, she says. But in time they devised a clever test. They grew the different mutated bacteria on glass covered by a thin metal film. Then they attached a wire to the bacteria. When they sent an electric current through the wire, they could measure how much the bacteria absorbed or added. If electrons didnt flow, the scientists knew the deleted genes must have been the ones needed for electron flow. 



In time, they narrowed in on five such genes that Shewanella apparently uses to absorb electrons. Each gene tells the cell how to make a protein. Some of those proteins likely grab electrons and bring them into the cell. Others may send signals within the cell that guide the process. Still others can likely expel electrons from the cell.





Bacterial biofuels



Scientists see many ways to use electric microbes. One would be to make biofuels. These differ from fossil fuels, such as coal and natural gas. (Fossil fuels are rich in carbon from decayed remains of ancient living things.) Ethanol, which can be made from corn or sugarcane, is a biofuel that can be added to standard gasoline. Cars that run on diesel can be adapted to run on another biofuel. Called biodiesel, it is fuel made from vegetable oil or animal fats.



Biofuels get their carbon from sources like plants or animal wastes. One day, they may even get their carbon with the help of bacteria, says Rowe.



This technician holds a biofuel sample, an alternative to fossil fuels. One day bacteria may be able to supply the power or the carbon needed to unleash a new wave of such renewable fuels.Sue Barrt/Image Source/Getty Images Plus



Shewanella is among bacteria thatcan pluck carbon atoms out of carbon dioxide. They can use it to create other, larger molecules that could be burned as a biofuel. And powered by the electrons it gobbles, Shewanella could keep making these molecules, Rowe says.



Knowing which genes drive the electron-eating could help scientists develop new biofuels, says Rowe. Even better would be if the electrons that feed the bacteria come from wind or solar power. Such sources could power the biofuel-making process without adding warming carbon dioxide to the air.



Elad Noor is an environmental scientist. He works at the Weizmann Institute of Science. Its in Rehovot, Israel. There, hes helping to develop new ways to fix carbon that is, to pull carbon from carbon dioxide to build other chemical compounds. Using bacteria to create biofuels is attractive because the bacteria can regenerate and should be able to repurpose the carbon. Soring energy in bacteria also would be green, he adds. After all, the microbes dont need dangerous metals, as a normal battery would.



However, working with living organisms is complicated, he warns. Biological systems are hard to predict, he says. There are ways to store energy that are much more efficient.



The genes that Rowes team found in Shewanella show up in other bacteria. The group plans to search for others that can store or release electrons. Rowe also wants to try to improve Shewanellas abilities, because these are the organisms we know the most about.

Dont watch TV close to bedtime. Put away your phone, too, or you may have trouble falling asleep. You may not realize it, but the blue light from device screens and even common lamps will confuse your brains internal 24-hour clock. Even white light contains these blue wavelengths. And when blue light enters the eyes, your brain gets the message that it needs to stay awake. But a new type of lighting appears to get around these sleep-challenging effects so you can nod off easily at bedtime.



This new light-emitting diode, or LED, might someday deliver the glow in lamps and other types of home lighting, its developers say. It might even find use in TV, laptop and smartphone screens, says Jakoah Brgoch. Hes a chemist at the University of Houston, Texas. He also helped design the new lighting technology.



He and fellow University of Houston chemist Shruti Hariyani have been studying the properties of phosphors. These substances glow when hit with light.



Explainer: Our bodies internal clocks





Light shines through the lens of an LED, usually a plastic bulb. Behind the scenes is an LED chip, which has small light-emitting diodes attached to a printed circuit board. When the chip is coated with powdered phosphors, the color of the light shining through the lens changes. The Houston team created a new phosphor to make their LED shine with a warm white light. Here, warm means the light contains less of the short, blue wavelengths that can mess with sleep.



Those same blue wavelengths are found in sunlight. And they tell your internal body clock that its time to be awake. Normally that body clock winds down as daylight fades. Melatonin is a hormone produced at night. It helps bring on sleep unless blue light tells your body otherwise. Blue light suppresses the melatonin hormone.



Explainer: What is a hormone?



And our bodies may well get confused if its late and our eyes remain bathed in blue light from devices or indoor lighting. Even though your body craves sleep, its still getting that signal for wakefulness.



Most modern screens and lighting systems use blue LEDs. They are energy efficient, long-lasting and cost little. But, Hariyani says, you have to be okay with the negative side effects [of their light] or fix it.



Shes part of a team thats choosing to fix it.





How to lose the blues



A new violet LED, shown here in a drawing, uses red, green and blue-emitting phosphors to combine the colors of the visible spectrum and create white light.S. Hariyani/University of Houston



Software helps some devices emit less blue light. For example, the iPhones night mode shifts its color palette. But this makes images look more red than normal, so users give up color quality. Plus, the LEDs in this and other smartphones still emit enough blue light to affect the bodys internal clock and melatonin production. People can block out some blue light by wearing yellow glasses near bedtime. However, this too will distort the hues in whatever youre viewing.



Says Brgoch, We wanted to know: Can we get to a high-quality light bulb with warmer and better quality light?



LEDs create white light by mixing red, green and blue hues. While these same primary colors of pigment in paint or crayons mix to make black, light works the opposite way. The white light shining out of an LED comes from the bulb color plus the colors of the phosphors used to coat the LED. Common house lighting uses blue LEDs coated with phosphors whose colors add to the LEDs colors to make white light.



A rarer type of LED has a violet bulb. Places such as museums and clothing stores install white lighting made using violet LEDs. Thats because these are designed to show an object’s true color better than the more common bluer LEDs used in most home lights. One drawback is that violet LEDs cost more. Still, Brgoch and Hariyani chose them for their prototype to get the best color.



Used in the new light, this phosphor glows blue when lit with a violet LED.S. Hariyani and J. Brgoch/University of Houston



To reduce their LEDs blue emissions, the chemists first altered a white powdered crystal that didnt glow on its own. They added a bright silver-colored element to the powders structure. This europium turns the crystal into a phosphor. Europium often is added to lighting phosphors because it helps boost the blue part of an LEDs glow. In this case, it made a true, high-quality blue good for use in an LED. That blue can combine with other colors to make white light.



The Houston team tested the new phosphor to make sure it wouldnt break down easily. They exposed it to heat and water. Not only did the phosphor continue to glow at the same intensity, but its color remained steady. Having all of these properties at once makes it superior to many other phosphors, Hariyani says.



Then they mixed the blue phosphor with red and green ones to create white light. The chemists added this combination to a modified violet LED. Compared to standard violet LEDs, this new one emits far less intense blue light.



Good white and good night?



A mixture of the new blue phosphor, together with red- and green-emitting ones, produces this warm white light when lit by a violet LED.S. Hariyani and J. Brgoch/University of Houston



Theres maybe a dozen phosphors used around the world in lightbulbs, notes Brgoch. To find something new thats on par with what you can buy is fantastic. And, he adds, its lower production of short, blue wavelengths should reduce its effect on someones nighttime secretion of melatonin.



But other aspects of light also influence the body, warns Mariana Figueiro. Her work at Mount Sinai Hospital in New York City focuses on how light affects the body clock and melatonin.



Brightness and colors of light other than blue such as green and yellow also affect the bodys natural readiness for sleep, Figueiro notes. To leave nighttime melatonin alone, she explains, A light source needs to have both low light levels and less blue light. She wonders if everyday lamps and screens could be dim enough not to interfere with the body’s internal clock and still be bright enough for practical use. Still, she says, its certainly worth studying.



To know if the new LED could help people who want to sleep better, scientists will have to measure its effect on melatonin.



This is science that is still relatively new to us, Brgoch says. As such, he says it will take some time for scientists to fully understand how to use the new LEDs in household items.



He and Hariyani shared their findings April 14 in ACS Applied Materials and Interfaces.

Did you know that arid deserts in several countries have turned into lush, fertile land? In countries such as the United Arab Emirates and China, fruits and vegetables now flourish, providing fresh produce for their inhabitants. But what caused this miraculous transformation? Lets find out! What is Nanoclay? In the 1980s, the Nile Delta in Egypt, known for its reliable farming, suddenly became barren. For decades, the Nile floodwaters had spread minerals, nutrients, and clay particles over the soil. However, the newly built Aswan Dam prevented clay particles from flowing, reducing the soils...

Memorial Day, whichwill be celebrated onMay 31, 2021,is one of the most important American holidays.Observed annually on the last Monday ofMay, it honors the brave men and women of theUS Army, Navy, Marine Corps, National Guard, Air Force, and the Coast Guard whosacrificed their lives to defend America's freedom. Meanwhile,Veterans Day, which takes place each yearon November 11, honorsall veterans living or deadbut mainly givesthanks to livingveteranswho served their country honorably during war or peacetime.

Donut lovers,rejoice!Friday,June 4, 2021, is National Donut Day. That means it is your civic duty to consume at least one oreven a dozen of the delicious confections. The fun US holiday, observed annually on the first Friday of June,was startedin 1938 by theSalvation Army to help raisefunds forthose in need.

Mythical mermaids are often known for their fishy tails and alluring songs. But if you were underwater with one, her tunes wouldnt sound quite like they do in the movies. And you might struggle to understand the words as Ariel or her other mermaid friends burst out singing.



Even next to a mermaid, the song would sound muffled and would seem to come from all around, says Jasleen Singh. You could still make out what she is saying, but it would sound fuller with less clarity, Singh says. She studies human hearing at Northwestern University in Evanston, Ill.





If mermaids existed, and if they sang and talked to one another, their hearing and sound-making setups might resemble marine creatures features instead of humans. To understand why, you have to start with the basics of sound and hearing.



Explainer: How the ears work



Sound is produced when an object vibrates. Touch your throat while you talk, and you can feel your vocal cords vibrating inside your neck. These vibrations can travel through gases, liquids and solids. In each medium, atoms and molecules get pushed around by a sound sources back-and-forth motion. These particles bump into each other in a rippling pattern of waves. Like a line of falling dominoes, the colliding particles spread sound.



Human hearing starts with sound waves entering the air-filled space in each earhole. The waves vibrate the eardrum, which wiggles three little ear bones. One of the bones taps on a snail-shaped structure in the inner ear called the cochlea. This fluid-filled structure converts the vibrations into electrical signals that the brain understands as sound.



Underwater, its a different story. Since water plugs your ears, you rely on sound waves directly vibrating the skull. This happens on land too, but it works better below the waters surface. Thats because water and bone have similar densities. When sound waves gently rattle the skull, that is directly stimulating the inner ear the cochlea itself, Singh says. This is called bone conduction. We humans, however, are much more attuned to the sound waves striking our eardrums. As a result, the sound quality of bone conduction is not as good as regular air conduction.



Plus, its difficult to figure out where a sound is coming from underwater. On land, if someone starts talking on your right side, sound waves hit your right ear before your left. This slight variation in timing helps your brain find the source of a sound. But sound travels much faster in water than in air. Thats because the particles that make up liquids are closer together. In water, there is virtually no time difference between sound hitting each ear. That makes underwater noise sound very full, like its coming from everywhere.









Our sea-dwelling relatives



To hear their friends talk and sing properly, mermaids might have evolved hearing structures more like aquatic animals.



Marine mammals, such as whales, dolphins and seals, hear in a way very similar to humans, notes Colleen Reichmuth. A biologist, she studies marine mammals at the University of California, Santa Cruz. These creatures have cochleae. They also have ear bones and eardrums, though not always functional. And they have evolved some adaptations to help them hear under the sea.





The lower jaw of dolphins and some whales contains fat that directs sound to the bony middle ear. This fat has a special chemical composition that makes it really suitable for transmitting acoustic waves, says Laela Sayigh. Shes a marine biologist at Hampshire College in Amherst, Mass., and Woods Hole Oceanographic Institution in Massachusetts.



Some marine mammals, such as seals, have convertible ears. On land, the animals can open ear holes to pick up sound waves traveling through air. But when diving, their ear tissue swells with fluid, plugging the holes. The fluid-filled ears help transfer sound from the water to the cochleae.





Those features could help a mermaid hear her friends songs more clearly. But if mermaid voices were more like those of marine mammals, their vocal systems could get a major upgrade, too.



Whales, dolphins, seals and other marine mammals can sing underwater, creating complex noises with musical notes or rhythms. They produce sound by passing air along tissues to vibrate them, similar to a humans voice box. But unlike people, who must breathe out to make noise, many of these sea creatures dont need to expel air from their mouths or blowholes to produce sound.



Underwater, air is a precious commodity, says Joy Reidenberg. If whales exhaled when using their voices, they would have to keep resurfacing for more air. That would interrupt their lengthy songs, Reidenberg says. She studies animal anatomy at the Icahn School of Medicine at Mount Sinai in New York City.



Instead, whales and dolphins can move air around in their bodies and even reuse it. This air recycling system would certainly help a mermaid sustain conversation or song below the surface, Reichmuth says.



For a voice that really carries, mermaids might be built like baleen whales. These whales, which include humpbacks, have huge vibrating structures in their throats that toss out sound. Some can make noises so loud and low-pitched too low for humans to hear that the songs could potentially travel more than 1,000 kilometers (600 miles) in the ocean. (Lower-pitched sound waves lose less energy when traveling through water than higher-pitched ones.)



Humpback whales sing beautiful, lengthy songs. But they dont need to breathe out of their mouths or blowholes to do it. These whales recycle the air supply in their bodies and can stay submerged for nearly an hour. Craig Lambert/iStock/Getty Images Plus



Something sounds fishy



A mermaids mammal upper half may not be the only part that could make or hear sounds. Crustaceans and fish are known to make quite a ruckus, too. In fact, snapping shrimps, typically around four centimeters (1.5 inches) long, are some of the loudest creatures on Earth. As the name implies, these shrimp snap one of their claws to produce a colossal sound.



Many fish use a similar method to make noise. They click or rub their bodys bony structures together. Sea horses, for example, produce clicks by knocking the tops of their skulls into the horns on their heads. They do this when wooing a mate.



You can think of it like clicking your teeth together, says Audrey Looby. A marine ecologist, she studies fish at the University of Floridas Nature Coast Biological Station in Cedar Key.



Other species can use their muscles to vibrate an internal organ, like playing a drum. Some fish can even communicate by expelling air out their backside, Looby says. Essentially, fish communicating through farting. And they have special cells lining the sides of their bodies that can sense vibrations in the water, helping them to hear.



If you met a mermaid, she might have both fish-like and mammalian structures to communicate with her underwater friends. Motion-detecting cells may line her tail, and her ears may work like a seals to hear both in and out of water. She would probably recycle her bodys air supply to talk and sing without having to keep resurfacing. But her conversations may also be sprinkled with teeth chattering, clapping and even farting.

Hello! This is the holiday contest. I know that the following options may not be your favorites. Don’t worry! Feel free to comment on your favorite, but please vote on the holidays listed below. The winners will have the chance to share their ideas, and I will even give a shout-out! Pick one and good […]

All known stars are made of ordinary matter. But astronomers havent completely ruled out that some could be made of antimatter.



Antimatter is the oppositely charged alter-ego of normal matter. For instance, electrons have antimatter twins called positrons. Where electrons have negative electric charge, positrons have positive charge. Physicists think the universe was born with equal amounts of matter and antimatter. Now the cosmos appears to have almost no antimatter.



Space-station data have recently cast doubt on this idea of a practically antimatter-free universe. One instrument might have seen bits of antihelium atoms in space. Those observations have to be confirmed. But if they are, that antimatter could have been shed by antimatter stars. That is, antistars.



Explainer: What are black holes?





Intrigued by this idea, some researchers went hunting for potential antistars. The team knew that matter and antimatter annihilate each other when they meet. That could happen when normal matter from interstellar space falls onto an antistar. This type of particle annihilation gives off gamma rays with certain wavelengths. So the team looked for those wavelengths in data from the Fermi Gamma-ray Space Telescope.



And they found them.



Fourteen spots in the sky gave off the gamma rays expected from matter-antimatter annihilation events. Those spots did not look like other known gamma-ray sources such as spinning neutron stars or black holes. That was further evidence that the sources could be antistars. Researchers reported their find online April 20 in Physical Review D.



Rare or possibly hiding?



The team then estimated how many antistars could exist near our solar system. Those estimates depended on where antistars would most likely be found, if they truly existed.



Any in the disk of our galaxy would be surrounded by lots of normal matter. That could cause them to emit lots of gamma rays. So they should be easy to spot. But the researchers only found 14 candidates.



That implies that antistars are rare. How rare? Perhaps only one antistar would exist for every 400,000 normal stars.



Understanding light and other forms of energy on the move



Antistars could exist, however, outside the Milky Ways disk. There, they would have less chance to interact with normal matter. They also should emit fewer gamma rays in this more isolated environment. And that would make them harder to find. But in that scenario, one antistar could lurk among every 10 normal stars.



Antistars are still only hypothetical. In fact, proving any object is an antistar could be nearly impossible. Why? Because antistars are expected to look almost identical to normal stars, explains Simon Dupourqu. Hes an astrophysicist in Toulouse, France. He works at the Institute of Research in Astrophysics and Planetology.





It would be much easier to prove the candidates found so far are not antistars, he says. Astronomers could watch how gamma rays from the candidates change over time. Those changes might hint at whether these objects are really spinning neutron stars. Other types of radiation from the objects might point to their actually being black holes.



If antistars exist, that would be a major blow for our understanding of the universe. So concludes Pierre Salati, who wasnt involved in the work. This astrophysicist works at the Annecy-le-Vieux Laboratory of Theoretical Physics in France. Seeing antistars would mean that not all of the universes antimatter was lost. Instead, some would have survived in isolated pockets of space.



But antistars probably could not make up for all the universes missing antimatter. At least, thats what Julian Heeck thinks. A physicist at the University of Virginia in Charlottesville, he too did not take part in the study. And, he adds, you would still need an explanation for why matter overall dominates over antimatter.

Hey guys! Welcome to this group. I am AthenaDaBest, and I am creating this for all people who LUVVV mythology and Percy Jackson fans and other Rick Riordan books, but other mythology series are allowed. Have fun!!

Whales, dolphins and porpoises all live in water, but theyre not fish. Theyre water-dwelling mammals known as cetaceans (Seh-TAY-shuns). This group includes the largest animals on Earth blue whales which can grow up to 29.9 meters (98 feet) in length. Most cetaceans live in the ocean, but there are a few species that live in freshwater or brackish water (water that is salty, but not as salty as the ocean). Cetaceans dont have gills as fish do. To get the oxygen they need, these mammals breathe in air through structures called blowholes.



Cetaceans are split into two groups based on what and how they eat. Toothed whales such as sperm whales, orcas (killer whales), dolphins, narwhals and porpoises all have teeth that help them catch prey. They eat fish, squid and other large critters. Orcas have been known to eat penguins, seals, sharks and other whales. Most species of toothed whales can use echolocation to find prey.



See all the entries from our Lets Learn About series



Baleen whales lack teeth. Instead, plates of baleen line their mouths. That baleen is made of keratin the same stuff as hair and lets the whale filter krill and other small invertebrates from the water to eat. Humpback whales in Alaska, though, have figured out they can get a free meal of tiny salmon by hanging out at fish hatcheries.





Scientists have had to get creative when it comes to studying these animals. One group figured out how to weigh a whale using drone imagery. Others use acoustic tags and other techniques to study the social lives of whales and dolphins. And sometimes scientists just get lucky. Like when researchers driving an underwater robot came across a decomposing whale at the bottom of the ocean and found an entire community feasting on the dead.





Want to know more? Weve got some stories to get you started:



Why some whales become giants and others are only big Being big helps whales access more food. But just how big a whale can get is influenced by whether it hunts or filter-feeds. (1/21/2020) Readability: 6.9



The social lives of whales New tools are giving scientists an unprecedented glimpse into the behaviors of whales and dolphins. And these new data are upending long-held assumptions. (3/13/2015) Readability: 7.0



Whales get a second life as deep-sea buffets When a whale dies and sinks to the seafloor, it becomes a feast for hundreds of different types of creatures. (10/15/2020) Readability: 6.6





The beautiful, haunting songs performed by some species of whales let the animals communicate over long ocean distances.



Explore more



Scientists Say: Krill



Scientists Say: Echolocation



Explainer: What is a whale?



Cool Jobs: A whale of a time



A whale of a journey



Drones help scientists weigh whales at sea



Whales feast when hatcheries release salmon



Killer whale blows raspberry, says hello



Sperm whales clicks suggest the animals have culture



Whales echolocate with big clicks and tiny amounts of air



Whale blowholes dont keep out seawater



Activities



Word Find



Learn more about whales and dolphins through crossword puzzles, coloring sheets and other activities from Whale and Dolphin Conservation. All of the activities are presented in English and Spanish. French and German translations also are available.

Imagine having a superpowerwould you rather fly high in the sky or breathe underwater like a fish? Flying would let you see everything from above while breathing underwater would help you explore the deep sea. Both sound fun, but which one would you pick and why? Comment your answers below!

Most runners pick their routes based on distance or surface type. Some pick flat roads for steady pacing, while others seek hills for a tougher workout. But for Lenny Maughan, running is about creating art one stride at a time.

New York City is widely known for its traffic gridlock and commuting times. It was even named the worlds most congested urban area for the past two years by a traffic data analysis firm. But this year, officials are trying to change that. On January 5, the city implemented a new policy that charges drivers to enter the most congested parts of Manhattan during rush hour. Let's find out more and how the new policy is being received. What is Congestion Pricing? The Congestion Relief Zone spans many frequented locations in Manhattan, including Wall Street, Times Square, SoHo, and Hells Kitchen...

On March 27, 2022, Troy Kotsur becamethe first Deaf male actor to win an Oscar.The 53-year-old, who won Best Supporting Actorfor his portrayal ofFrank Rossi in "CODA," isonly the second Deaf actor to attain the prestigious award. In 1987,Marlee Matlin took home the Best Actress awardfor her role as Sarah in the movie "Children of a Lesser God."

Major textbooks used by most introductory biology classes in U.S. high schools contain overly simplistic and misleading language when describing sex and gender. Thats the finding of a new study.



The study authors worry that such faulty teaching may be used to justify sexism or prejudice against certain segments of society.



Brian Donovan is an education researcher at BSCS Science Learning. Its in Colorado Springs, Colo. The center develops materials for classrooms and teachers. It also evaluates how science and technology are taught. Donovans team looked at six widely used high-school biology textbooks. Nationwide, about two out of every three intro classes in biology use one of these texts.



The researchers scoured each book, looking for passages that dealt with biological sex and gender. In all, they found 362 paragraphs in genetics chapters that dealt with these topics. And in each book, at least some passages erred in how they described sex or gender. The study also turned up problems with how the books taught about traits linked to genes.



The researchers shared their findings February 24 in Science.





This short video by Encyclopaedia Britannica reviews the difference between sex and gender, pointing out how they can differ.



The impact of textbooks



How such topics are presented can affect students beliefs about whos good at science, Donovan has found. Back in 2019, his team randomly assigned 460 eighth to tenth graders to read one of three genetics passages. The readings differed in how they described what role genes play in differences between sexes. Later, the team surveyed these kids about why they think some people are good at science.



Some of the readings gave an oversimplified version of how genes determine differences between sexes. For example, they described basic genetic differences between men and women based on X- and Y-chromosomes. Students who read these passages were more likely to think that someones academic ability was set by genes, too. Such thinking could lead to false beliefs that males and females have different abilities in some fields. This includes success in STEM fields: science, technology, engineering and math.



Artists rendition of our gene-carrying chromosomes. Teaching an oversimplified version of genetics can lead to mistaken beliefs that males and females have different abilities based on their genes, one study finds. Rost-9D/iStock/Getty Images Plus



Whats more, these ideas seemed to affect girls views about themselves. Many of those who read the overly simplistic lessons showed less interest in pursuing careers in science-related fields, compared with girls who had gotten other information.



These results are important because gender stereotypes start young. Sexist attitudes about how smart someone is including oneself can begin by first grade. A limited understanding of biology might support those attitudes. And it could help explain why fewer women seek careers in science and engineering.



Either/or traits are rare



The researchers found that the textbooks tended to focus on so-called “either/or” traits. These are discrete traits that you either have or you dont. But such traits are actually rare. Some textbooks describe being able to roll your tongue as a discrete trait. Its not. Some of us can roll our tongues a lot. Others can barely do it. The rest fall somewhere in between.  



Most traits vary like this. They reflect the impacts of many different genes, says Donovan and how those genes interact with the environment.



Height is one example. Genes can generally influence how tall we get. But so does the environment. Someone who had good health and a good diet throughout childhood will tend to grow taller than those who lacked one or both.



Sex can vary across a spectrum, too. But some textbooks present it as a discrete trait: male or female.




Sex as a spectrum



Sudowoodo/iStock/Getty Images Plus
Sex and gender are two different things. Textbooks, however, often not only treat them as the same, but also leave out an important variation present in many people: intersexuality.





Doctors assign sex at birth based on visible genitals. Most people are labeled as female if they have a vulva, or male if they have testes and a penis. But there are also millions of people whose bodies are not strictly male or female. These people are referred to as being intersex. There was no mention of intersex individuals in any of the books reviewed for the new study.



A mixture of genetics and the environment can influence peoples traits. For instance, exposure in utero to some foods and pollutants can mimic sex hormones. That can affect whether people (and animals) develop certain feminine or masculine features.





What does intersex mean? This short video explains how some people are not strictly male or female.



Genetics is not the sole basis of gender



Females usually have two X-chromosomes; males usually have an X- and a Y-chromosome. However, chromosomes and genitals do not set our gender. Gender is different than sex, points out Catherine Riegle-Crumb. She is a sociologist at the University of Texas at Austin and one of the new studys authors. A transgender male, for example, might have two X-chromosomes, but his gender is still male.



Gender has to do with our beliefs and ideas about males and females, explains Riegle-Crumb. We inherit gender from our culture. What is considered normal behavior and preferences for males, females or nonbinary people varies between cultures. It also can change over time.



These expectations called gender norms affect how society treats people. And it starts even before a baby is born. (Think gender reveal parties: pink for females, blue for males.)



Yet in the new study, none of the 362 paragraphs on such topics described the difference between sex and gender. And if students dont learn the difference, Riegle-Crumb worries, they may assume gender differences are due to sex. It can also make it harder for students to accept transgender people, whose gender doesn’t match the sex they were assigned at birth.



Assumptions could lead students to use genes to explain other differences they see, too. For example, social differences. Why arent there more women leaders? The answer is not found in their genes. Still, students may think it is.




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Do you have a science question? We can help!



Submit your question here, and we might answer it an upcoming issue of Science News Explores




The studied books also left out the many ways men and women are similar, Riegle-Crumb notes. Nor did they describe the normal range of differences between people within a group. For example, some men have more feminine features. Some women have more masculine ones.



The books focused instead on the traits women tend to share with women, or men with men.  This gives the impression that all women are kind of the same (and so are men).



These books explained differences between people largely on the basis of genes. They gave gene-based reasons 12 times as often as external-factor reasons. External factors include what society expects of us or how our genes may interact with the environment. In fact, genes alone dont explain most differences between people, Donovans team points out.



Nowhere did the books write that genders have different STEM abilities. But kids can come to that false conclusion, Donovan says. Its something his team saw in its 2019 study.





This video explains, using science, why its not only outdated but also wrong to think there are just two human sexes.



Unscientific beliefs linked to prejudice



The new studys findings are important but not surprising, says Zach Schudson. Hes a social psychologist at California State University in Sacramento. He did not take part in the new work. But he does study how beliefs about gender and our bodies can affect how we view ourselves and others.



Says Schudson, the first time most of his students hear about intersex people is in a college class. The new study, he says, helps explain why. Not recognizing that many people wont fit squarely into a male or female category can lead to prejudice against those who seem different from norms, he says.



These beliefs also can affect someones views on gender equality. One 2018 study, for instance, showed that people who believe men and women have distinct capabilities based on their genes were less likely to support equal pay for women. People with such beliefs also may question whether women should be leaders, says Riegle-Crumb.



One way to combat unscientific messaging is call it out, says Riegle-Crumb. People naturally exhibit a diverse range of traits. Dont try to fit everyone into a few simple boxes. Instead, she suggests, notice both the many traits people share and the ways we differ.

Who’s up for a challenge? Create a caption for this image, and the one with the funniest, wittiest, and most creative one wins! You can also post your own funny image as a comment and others can create a caption in the replies under it!

So, in my ELA class, we had to read an excerpt from “I Know Why The Caged Bird Sings” by Maya Angelou and it’s totally insane! This woman went through soooo much from age 8 to 16; She was sent to her grandmothers house in Arkansas from California, and was then sent back and abused […]

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The African Serengeti looks much like it did hundreds of years ago.



Huge herds of wildebeests, over one million strong, still roam the savanna. Lions, hyenas and other top predators stalk the herds. This keeps their prey from eating too much vegetation. Diverse trees and grasses support scores of other species, from vivid green-orange Fischers lovebirds to dung beetles. In turn, such species carry seeds or pollen across the plains, aiding the spread of plants.



Overall, the Serengeti is a prime example of what biologists call an ecologically intact ecosystem. A bustling tangle of relationships work together. This sustains a rich diversity of life. People are there, but represent only a small part of the whole. And they dont disrupt the rest of the system.



Such places are vanishingly rare. Ecosystems on nearly all the Earths land a staggering 97 percent no longer are intact. Thats according to a sweeping new survey of Earths land-based ecosystems. Over the last 500 years, many have lost habitat or species. In others, populations of key animals have shrunk. Just 3 percent of the surveyed lands are unchanged, researchers reported April 15 in Frontiers in Forests and Global Change.



People have damaged forests around the world, destroying habitats and threatening species. This Indonesian rainforest has been cut to build plantations of palm oil, for instance. Photography by Mangiwau/Moment/Getty Images



Even the few remaining intact ecosystems may be at risk. Only about 11 percent of them are within protected areas, the researchers found. Much of the intact land overlaps areas that now are or were historically managed by Indigenous people. Those people often have played a vital role in maintaining healthy ecosystems, the researchers say. One way these habitats could be conserved, many scientists think, would be to make sure that Indigenous communities retain legal rights to manage these lands.



Much of the last pristine habitat exists in the far North. Think Canadas boreal forests or Greenlands icy tundra. Neither are bursting with biodiversity. But chunks of rainforests in the Amazon, Congo and Indonesia still host species-rich ecosystems.





These are the best of the best. The last places on Earth that havent lost a single species that we know of, says Oscar Venter. He works at the University of Northern British Columbia in Prince George, Canada. He is a conservation scientist who did not take part in the new study. Its crucial to identify these ecological gems, he says. Some may be under threat of development. Among those is the Amazon rainforest. Mapping where these largely unaltered sites are is the first step toward protecting them.



Conservation scientists have long tried to map humanitys touch. Previous estimates used data on where people live. Others used images from satellites. Such images can reveal physical changes, such as roads and damaged forests. They even can show indirect effects such as light pollution. In those studies, 20 to 40 percent of the globe appear little changed by people.



But many human effects may not be obvious, notes Andrew Plumptre. He is a conservation biologist at the University of Cambridge in England. Hunting, the impacts of invasive species, climate change, Plumptre notes. These can harm ecosystems. But they cant be easily sensed via satellite. Imagine the Serengeti with fewer lions or hyenas or none at all. It would look the same from space. But it would be missing key species that help the whole ecosystem run.



Plumptre wanted another way to measure the influence of people. He and his colleagues looked for ecosystems that havent changed as human populations have grown and spread. They defined an intact ecosystem as one that has all the same species today and at the same levels as it did in 1500. (The International Union for the Conservation of Nature starts from that year when counting species extinctions. Even long before that, though, people changed nature, such as by wiping out big mammals.)





Where the wild things (still) are



The team combined several types of existing data. They looked for places where habitats seem undisturbed by people. And they used three different measures of where species have been lost. The data covered about 7,500 animal species. Put together, the data showed undisturbed regions that had kept all their critters.



Some wide-ranging species need large swaths of land. So the researchers first looked for areas larger than 10,000 square kilometers (3,900 square miles). (Thats roughly the size of Puerto Rico.) Only 2.9 percent of undisturbed land areas that big still hold all the species they did 500 years ago. Then they looked at smaller areas, of 1,000 square kilometers (390 square miles). That bumped the percentage up just a bit, to 3.4.




Degraded ecosystems



Human activity has effects that reach nearly the whole globe. Many areas have lost species, as color-coded on this map. Based on a survey of about 7,500 animal species, purple areas show the 3 percent of land where no known species have been lost since the year 1500.



Lost species in the wilderness



A.J. Plumptre et al/Frontiers in Forests and Global Change 2021



A.J. Plumptre et al/Frontiers in Forests and Global Change 2021




Theres more to an ecosystem than just whos in it, though. Lower numbers of key species can also throw a system out of whack. The researchers tallied up the population densities of 15 types of large mammals. These included gorillas, bears and lions. Together, the chosen species span much of the globe. Why large mammals? They play important roles in ecosystems, Plumptre explains. The best historical data exist for these. They also are often the first to be affected by human neighbors.



Some of those mammals had declined in places that were otherwise intact. Accounting for dropped the ecologically intact total down to 2.8 percent of all land.



Overall, the tally of intact ecosystems was much lower than we were expecting, Plumptre says. Going in, Id guessed that it would be 8 to 10 percent. It just shows how huge an impact weve had.



Understanding the challenge



Jedediah Brodie is a conservation ecologist at the University of Montana in Missoula. He and Venter both wonder if the study authors were too strict in how they defined intact.



Many ecosystems around the world have lost one or two species but are still vibrant, diverse communities, Brodie says. In such places, a drop in a few species may not spell disaster for the whole ecosystem. Other species may swoop in to fill those roles.



Still, the study is a valuable first look. It shows us where the world looks like it did 500 years ago and gives us something to aim for, Plumptre says. It also identifies areas that could be restored. Adding back up to five lost species could restore 20 percent of land to its former glory, the researchers calculate. 



Reintroducing lost species has worked well in some places. In Yellowstone National Park, bringing back wolves has put the ecosystem back into balance. Such schemes may not work everywhere. But deciding how to protect nature is a growing, global challenge. Plumptre hopes policy makers will take note. Its possible to not just protect the land thats there, but also think about restoring it to what it could be.



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Im sure youve heard of Lake Superior and Big Bear Lake, but have you heard of Tulare Lake? Tulare Lake has a long history in the state of California, and was once known as the largest body of freshwater west of the Mississippi River. Unfortunately, it was drained for commercial reasons and has continually been pumped out for hundreds of years. But what led to its drainage, and can it be restored? Lets find out! History of Tulare Lake Located in the San Joaquin Valley (SJV), Tulare Lake was once 100 miles long and 30 miles wide. It was named after the tule reeds that surrounded its shore...

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Researchers worldwideare celebrating the discovery ofthe fossil of an adult oviraptorosaur broodingover a nest of eggs containingunhatched babies.Theunprecedented discoveryconfirms scientists' suspicions thatthe two-leggedbird-like dinosaursweredoting parents, whichnot only incubated their eggs, but also guarded themat times putting their own lives at risk.

Hello, My Munchkins! Today, I have 5 tips for new people or just curious people. Lets get started! ONLY MEMBERS CAN FRIENDPEOPLE Alright, gang, you heard it. Only members can be friends. To become a member, press register at the top right, then fill out your username, password, and email. Simple as that! WHEN COMMENTING […]

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Invasive species can wreak havoc on ecosystems. These organisms settle into and cause harm in places where they arent native. For example, mosquitoes spread diseases. Cats kill birds and some mammals. Many insects chew up crops or kill trees. Such damage can be very costly. So is managing the mayhem they cause. New research suggests that just between from 1970 and 2017, invasive species cost the world at least $1.28 trillion.



By estimating the global cost, we hoped to raise awareness of the issue, Boris Leroy tells Science News. A biogeographer, Leroy studies how life, such as plants and animals, spread across regions. He works at the French National Museum of Natural History in Paris. Researchers have studied invasive species for decades, he says. But many people remain unaware of the problems these eco-bullies cause.



Leroy and his team set out to tally that cost. They scoured research papers for estimated costs of specific invasions. They came up with 1,319 studies to analyze. To find long-term trends in costs of invasions, the researchers used a computer model. It let them account for currencies used in different countries and how the value of money changed over time.







The new study examined costs of dealing with damage plus the cost of managing the species. Damage control cost about $892 billion. Thats 13 times more than the $66 billion spent on such efforts as ousting invaders or controlling their spread. The total yearly cost of invasive creatures doubled roughly every six years between 1970 and 2017. In 2017, that annual bill reached $162.7 billion, the team reports March 31 in Nature.



Scientists Say: Invasive species



Many invaders hitch a ride to new places via cargo ships and planes. So inspecting cargo or monitoring for new pests could help lower the cost of invasions, says ecologist Helen Roy. Its much cheaper than waiting for the species to establish and spread widely before responding, she says. Roy works at the U.K. Centre for Ecology and Hydrology in Wallingford, England. She was not involved with the study.



The new results are likely an underestimate. Thats because research on invasive species doesnt capture the whole problem. For instance, more reports focus on North America and Europe than on whats happening in South America or Africa. And pests that harm crops, such as insects, get more attention than do invasive plants. However, Roy notes, the study does show that invasive species are a massive problem thats getting worse.




Costly critters



Researchers analyzed papers from the past few decades to pin down the most expensive invaders. This bar graph shows the results. Total costs for each species are broken down into three categories: damages, costs for managing the species and mixed costs. Mixed costs dont fit neatly into either damage or management costs.    



The top 10 costliest invasive species, 19702017



E. Otwell



E. Otwell



Source: C. Diagne et al/Nature 2021




Data Dive:



What was the cost of the most expensive invasive species?



Look at the different colors making up that first bar. Roughly how much of the total cost is due to damage? How much of the cost is due to management?



Which three invasive species have cost the most damage? What is the total damage cost of these three creatures?



Which invasive species has the highest management cost?



How many of the 10 costliest invaders are insects? How many are mammals? How many are reptiles?



Choose one of the species. What kinds of damage can this creature cause? How might this animal affect other wildlife? How might it affect people? How might this animal affect crops or buildings?



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Objective: To measure the effect of temperature on the rate of a chemical reaction



Areas of science: Chemistry, science with your smartphone



Difficulty: Easy intermediate



Time required: 25 days



Prerequisites: None



Material availability: Readily available



Cost: Very low (under $20)



Safety: Adult supervision may be needed when working with hot water solutions



Credits: Andrew Olson, PhD, Science Buddies; edited by Svenja Lohner, PhD, Science Buddies






You may have seen a television commercial for Alka-Seltzer tablets or heard one of their advertising slogans: Plop, plop, fizz, fizz, oh what a relief it is! When you drop the tablets in water, they make a lot of bubbles, like an extra-fizzy soda, as shown in the main image up top (Figure 1). And like a soda, the bubbles are carbon dioxide gas (CO2). However, with Alka-Seltzer, the CO2 is produced by a chemical reaction that occurs when the tablets dissolve in water.





Alka-Seltzer is a medical drug that works as a pain reliever and an antacid (antacids help neutralize stomach acidity, such as heartburn). The pain reliever used is aspirin and the antacid used is baking soda (sodium bicarbonate, NaHCO3). To take the tablets, they should be fully dissolved in a glass of water. When sodium bicarbonate dissolves in water, it dissociates (splits apart) into sodium (Na+) and bicarbonate (HCO3) ions. (An ion is a molecule that has a charge, either positive or negative.) The bicarbonate reacts with hydrogen ions (H+) from citric acid (another ingredient in the tablets) to form carbon dioxide gas and water. In other words, carbon dioxide gas is a product of this reaction. The reaction is described by Equation 1 below:



Equation 1.3HCO3 + 3H+ 3H2O + 3CO2



So how is temperature related to this bicarbonate reaction? In order for the reaction shown above to occur, the bicarbonate ions have to come into contact with the hydrogen ions. Molecules in a solution are in constant motion and are constantly colliding with one another. The hydrogen and bicarbonate ions must collide at the right angle and with enough energy for the reaction to occur. The temperature of a solution is a measure of the average motion (kinetic energy) of the molecules in the solution. The higher the temperature, the faster the molecules are moving. What effect do you think temperature will have on the speed, or rate, of the bicarbonate reaction?



In this chemistry science project, you will find out for yourself by plopping Alka-Seltzer tablets into water at different temperatures and measuring how long it takes for the chemical reaction to go to completion. In addition, you can record the sound of the Alka-Seltzer fizzle using a smartphone equipped with a sensor app. Do you think it will fizz more loudly in hot or cold water?



Terms and Concepts




Chemical reaction



Alka-Seltzer



Baking soda, or sodium bicarbonate



Molecule



Products



Temperature



Bicarbonate reaction



Reaction rate




Questions




What is the bicarbonate reaction? What are its products?



Keeping in mind that an increase in temperature reflects an increase in the average molecular motion, how do you think increasing temperature will affect the reaction rate?



What temperature change do you think would be required to increase, or decrease, the reaction time by a factor of two?



What other factors besides temperature can affect how well a chemical reaction takes place?




Materials and Equipment




Alka-Seltzer tablets (at least 12; if you plan to do additional variations to the project, you will want to get a larger box)



Thermometer with a range of at least 0C to 60C (32F to 140F)

A suitable thermometer is available from Amazon.com



A standard kitchen candy thermometer will also work fine





Clear drinking glasses or jars; about 8 ounces, or 240 milliliters (two of the same size)



Graduated cylinder, 100 mL. A 100 mL graduated cylinder is available from Amazon.com. Alternatively, measuring cups may be used.



Masking tape



Hot and cold tap water



Ice



With option 2 in procedure: Stopwatch or a clock or watch with a second hand



Optional: A helper



Lab notebook



Pencil



With option 1 in procedure: Smartphone with a sensor app such as phyphox, available for free on Google Play for Android devices (version 4.0 or newer) or from the App Store for iOS devices (iOS 9.0 or newer).



With option 1 in procedure: Small sealable (waterproof) plastic bag that fits your phone inside of it




ConditionTemperature(C)Reaction Time(s)Optional: Maximum Sound Intensity(dB)Trial #1Trial #2Trial #3AverageTrial #1Trial #2Trial #3AverageHot Tap Water         Cold Tap Water         Ice Water         Table 1. In your lab notebook, make a data table like this one. You will record your results in it.



Experimental Procedure



Note: In this science project, you will investigate how water temperature affects the dissolving time of an Alka-Seltzer tablet. You will use a smartphone equipped with a sensor app to record the fizzing sound of the Alka-Seltzer reaction in water and measure the time it takes for one Alka-Seltzer tablet to react completely in water. The app creates a graph that will not only give you information about the reaction time but will also allow you to assess how loud each reaction was based on the measured sound intensities. If you do not have a phone, you can observe the reaction and use a stopwatch to time how long it takes for each tablet to dissolve.



Figure 2. Mark your glass on the outside with masking tape to indicate a water level up to about 1 inch below the rim.M. Temming



Do your background research and make sure that you are familiar with the terms and concepts in the Background.



In your lab notebook, make a data table like Table 1. You will record your results in this data table.



Prepare a drinking glass so that it is marked at the 200 mL point. You will use the same glass for multiple trials, so it is convenient to mark the desired water level. Note: If your glass fits more than 8 ounces, make a mark about 1 inch below the rim.

Add 200 mL (a little less than 1 cup) of water to the drinking glass, or fill it up to about 1 inch below the rim.



Use a piece of masking tape on the outside of the glass to mark the water level, placing the tape with its top edge even with the water level in the glass, as shown in Figure 2.



Note: You do not want to fill the glass completely full because the bicarbonate reaction produces bubbles that could splash out.





You will fill the drinking glass with the same volume of water at three different temperatures: hot tap water, cold tap water and ice water.

For the hot and cold tap water, run the water until the temperature stabilizes. Fill the glass with water to the level of the masking tape. Be careful when handling the hot water.



For ice water, fill the glass about half full with ice cubes, then add cold tap water to a bit above the level of the masking tape. Stir for a minute or two so that the temperature equilibrates. Once temperature has equilibrated, remove the ice cubes from the water’s surface using a spoon or other utensil immediately before adding the Alka-Seltzer tablet. (Pour out any extra water so that the water is up to the level of the masking tape.)





Prepare the drinking glass with one of the three temperatures as described in step 4. Then measure the reaction time for that temperature either by following option 1 (sensor app), described in step 6, or option 2 (stopwatch), described in step 7.

If you use the phyphox app to measure the amplitude of sounds, you will need to calibrate the sensor first to get correct decibel readings on your device. The sensor has to be recalibrated between individual recordings. Instructions on how to do the phyphox sound sensor calibration are provided in the video above.



Option 1: Using the Sensor AppSensor apps such as phyphox let you record data using sensors that are built into many smartphones, including a microphone that you can use to measure sound. In this project, you can use the app to record the fizzing sound that the Alka-Seltzer tablet makes while it dissolves in water and then use the data to determine the reaction time and maximum sound intensity for each reaction.



Open the sensor app on your phone and select the sound sensor (audio amplitude in phyphox). Remember, that when you are using the phyphox app you will have to calibrate the audio amplitude sensor (sound sensor) before you do any measurements. Do this calibration before you start your investigation, so you get correct sound intensity readings. To calibrate your sound sensor in phyphox, follow the instructions in the sound sensor calibration video. You will have to re-calibrate the audio amplitude sensor (re-set the decibel offset) every time you start a new recording! Once you have calibrated the sensor, make sure you know where the microphone is located on your phone and do a quick test to see if your sound measurement is working. For example, you could record yourself clapping or singing to check if the sensor behaves as expected.



Once you have confirmed that the sensor works and you are familiar with the app, you can start with the experiment. You should do this experiment in a quiet environment. The background reading of your sound meter when there is no noise in the room should be in the range between 2040 decibels (dB).



Measure the temperature of the water (in Celsius [C]) in the first glass that you prepared, and record it in the data table in your lab notebook. Remove the thermometer from the glass before continuing with the next step.



Put your phone in the waterproof plastic bag and make sure it is sealed well. You don’t want it to get wet!



Place the second, same-sized glass, next to the glass filled with water. Lay your phone on top of the second glass so that the microphone (or sound sensor) is located right at the center above the glass filled with water, as shown in Figure 3.Figure 3. Place your phone on top of the glass filled with water so that the microphone (or sound sensor) is located right at the center above the solution.M. Temming





Take one whole Alka-Seltzer tablet out of its package and hold it above the glass filled with water. In the phyphox app, start a new recording for your first experiment by pressing the play button.



Once the recording starts, drop the tablet into the water. Note: You have to be very quiet during the experiment. Any sound that you make will be recorded and could affect your data. Try to be as quiet as possible while you are recording your data!



You will immediately see and hear bubbles of CO2 streaming out from the tablet.



The tablet will gradually disintegrate. Observe the graph recorded by the app, and how the sound sensor is responding to the fizzling while all of the solid white material from the tablet disappears.



When the solid material has completely disappeared, and you see on the graph that the sound intensity has reached background levels again or does not change anymore, wait 20 more seconds until all the bubbles have stopped forming, and stop recording your data. Make sure to save your data and label it appropriately such as “hot water,” “cold water” or “ice water.” Figure 4. This example data from the phyphox app demonstrates how to measure the reaction time of the Alka-Seltzer tablet dissolving. The x-axes of the graphs are time in seconds [s] and the y-axes shows sound intensity in decibels [dB].Made with phyphox by M. Temming





Your data should look something like the graph in Figure 4. Your graph should show an increased sound intensity for as long as the Alka-Seltzer reaction took place. The sound level of the reaction might be louder in the beginning and decrease as the tablet gets smaller. In the graph, every bubble that pops in the solution is represented by a spike.



Measure the time between the beginning of your reaction (when you dropped the tablet and the sound intensity started to increase) and the end of the reaction (when the sound intensity reached background levels again or does not change significantly anymore). In phyphox, you can use the pick data function to select the respective data points and view their time and decibel values. For example, the reaction in Figure 4 started a little after 3 seconds and ended at about 66 seconds.



Calculate the time difference between these two points. The result is the reaction time for your first trial. Record the reaction time (in seconds [s]) in the data table in your lab notebook.



Tip: Be careful when opening the packets and handling the Alka-Seltzer tablets. The tablets are thin and brittle, so they break easily. If some of the tablets are whole, and some are broken into many pieces, the separate trials will not be a fair test. You should only use whole tablets.





Option 2: Using the stopwatch

After filling the glass to the level of the masking tape, measure the temperature of the water (in Celsius [C]), and record it in the data table in your lab notebook.



Remove the thermometer from the glass before continuing with the next step.



Have your helper get ready with the stop watch, while you get ready with an Alka-Seltzer tablet. Have your helper count onetwothree. On three, the helper starts the stop watch and you drop the tablet into the water.



You will immediately see bubbles of CO2 streaming out from the tablet.



The tablet will gradually disintegrate. Watch for all of the solid white material from the tablet to disappear.



When the solid material has completely disappeared, and the bubbles have stopped forming, say “Stop!” to have your helper stop the stopwatch.



Record the reaction time (in seconds [s]) in the data table in your lab notebook.



Tip: Be careful when opening the packets and handling the Alka-Seltzer tablets. The tablets are thin and brittle, so they break easily. If some of the tablets are whole, and some are broken into many pieces, the separate trials will not be a fair test. You should only use whole tablets.





Repeat step 6 or 7 two more times with the same temperature of water. If you use the sensor app, make sure your sound sensor is still calibrated and recalibrate it again (re-set the decibel offset) if necessary before each recording.

Repeating an experiment helps ensure that your results are accurate and reproducible.





Repeat steps 5 and 6 or 5 and 7 for each of the other temperatures.

When you are done, you should have done a total of three trials for each of the three temperatures.





Calculate the average reaction time for each of the three water temperatures. Record your results in the data table in your lab notebook.



Make a graph of the average reaction time, in seconds (on the Y-axis), vs. water temperature, in degrees Celsius (on the X-axis).



How does reaction time change with temperature? Can you explain why this is?

Hint: If you are having trouble explaining your results, try re-reading the Introduction in the Background.





If you chose to use a sensor app to record your data, look at the graphs for each water temperature again. Write down the maximum sound intensity that you observed during the Alka-Seltzer reaction (not including the initial or end peaks) for each trial. You can get the number in the phyphox app by using the pick data tool to select the timepoint at which the sound intensity is highest. In the example shown in Figure 4, this would be around 35 seconds with a sound intensity of about 50 decibels. Calculate the average for each of the three water temperatures and record your results in the data table in your lab notebook.



Make a graph of the average maximum sound intensity, in decibels (on the Y-axis), vs. water temperature, in degree Celsius (on the X-axis).



Which reaction was the loudest? Did you expect these results?






Variations




More advanced students should also calculate the standard deviation of the reaction times for each temperature.

Use the standard deviation to add error bars to your graph.



For example, say that the average reaction time for one temperature was 45 seconds, and the standard deviation was 5.2 seconds (these are made-up numbers). You would graph the symbol for the data point at 45 seconds, and then draw short vertical bars above and below the symbol. Each vertical bar would have a length equivalent to 5.2 seconds.



Error bars give your audience a measure of the variance in your data.





Adult supervision required. Is reaction rate predictable over a larger temperature range? Water remains liquid above 0 C and below 100 C. Repeat the experiment at one or more additional high temperatures to find out. Use Pyrex glass for containing water heated on the stove or in the microwave, and use appropriate care (e.g., wear hot mitts and safety goggles) when handling hot water. A standard candy thermometer should be able to measure the temperatures in this higher range.



You could turn the bicarbonate reaction into a home-made lava lamp. To do this, you will want to use a tall jar or empty clear plastic 1-liter or 2-liter bottle, fill it with 2 to 5 centimeters (cm) of water, add 5 drops of food coloring, and then fill it at least three-quarters full with vegetable oil. You could repeat the science project using your homemade lava lamp at a cold and a hot temperature. To do this, you will need to figure out a way to make the prepared bottle hot or cold. (For example, to make it hot you could let it sit in a large bowl of hot water, and to make it cold you could store it in a refrigerator or freezer.) You will also want to use one-quarter of an Alka-Seltzer tablet at a time (instead of a whole tablet). How does the bicarbonate reaction look and function in the home-made lava lamp?




This activity is brought to you in partnership with Science Buddies. Find the original activity on the Science Buddies website.

Virtual reality (VR) headsets arent without their risks. Users can bump into walls, furniture or even other people. Niall Williams is looking to fix that. This computer scientist makes programs that keep people safer while using VR. He works at the University of Maryland in College Park. 



Williams works with redirected walking. This technique nudges users along a path in the real world by subtly changing their virtual display. Developers can tweak how VR programs represent traveling distance, says Williams. For example, algorithms can make two feet of walking in the real world cover more virtual ground. This lets users walk naturally while exploring large digital spaces.



Fast or large adjustments can leave users disoriented and queasy, though. Redirected walking also works best in areas with fewer obstacles. To help, Williams designed a program that calculates a safer path for users. It avoids both physical and virtual obstacles. We kind of play tricks on people to get them to walk around safely, says Williams. 



His algorithms stopped more collisions than other redirected walking programs. By using slower changes, they also lower the odds of motion sickness. Williams is exploring other ways to use natural walking in virtual spaces, he says. In this interview, Williams shares his experiences and advice with Science News Explores. (This interview has been edited for content and readability.)



What inspired you to pursue your career? 



I wanted to study biology, but I wasnt good at chemistry. I liked programming and got some experience in high school. So I decided to do a computer science degree. After a few years, I learned about computer graphics. It’s a combination of all of my interests. I also really enjoy video games, animations and art.  



I’m doing this research because working on new problems is fun for me. I like learning about how the human visual system works, and why images evoke certain responses from people. When you see a cartoon person, it’s clearly not a realistic image. But you can still tell that it’s a person in some way, even though the proportions are totally incorrect.  



How did you get to where you are today? 



There are a lot of PhD students in my lab that work on different things. In our lab meetings, the students studying robotics would discuss problems they were working on. I saw this interesting intersection between robotic navigation and VR locomotion. Robot navigation is getting from one point in the environment to another point without getting stuck. Sort of like how your Roomba knows where to go in the room to figure out where it needs to clean. That has a lot of similarities with locomotion in virtual reality. 



A big problem in VR locomotion is that you’re seeing a virtual environment through the headset, but you’re physically located in a different environment. If you want to reach some destination in the virtual world, your path to that destination is likely blocked by some physical objects.  



I realized that I could probably sort of combine the two fields after talking with my lab mates. I could apply techniques for robot navigation to this VR locomotion problem. This might help people avoid objects when they’re in VR. It worked out, so I continued on that path. 



What would you say is your biggest success? 



Probably my first published paper that goes toward my dissertation. I had the idea of applying motion-planning techniques from robot navigation to this VR navigation problem. But nobody had done it before, and it was [during] the pandemic. I was stuck in my house and had to figure it out, largely on my own. During the first two months of that summer, it wasn’t working out. I met with my PhD advisors to discuss the technical details and then took a step back.  



I came up with some algorithms that led to better performance in certain situations. I implemented the research idea, and it worked. We then turned that into a paper that got published. The paper was very well received in my community of scientists. 



Niall Williams tested his algorithm in different physical and virtual scenarios. In one test, the virtual environment was larger than the physical space available. The program guided the user along a curved route in the physical world to compensate (left). In another test, the program had to navigate a straight virtual path while avoiding real-life objects placed in front of the user (right). N. Williams



What was one of your biggest challenges and how did you get past that? 



I did an internship at the company Meta (the parent company of Facebook and Instagram). It was more focused on researching human perception in virtual reality, which I don’t have formal training in. Instead of working with computer scientists, I had to learn how to work with people who study human perception, such as psychologists. Figuring out how to bridge that gap and learn how to do science in the way they do was a challenge for sure.  



How do you get your best ideas? 



My best ideas come from talking to other people and reading papers from different scientific disciplines. This world of extended reality is a very interdisciplinary field. Computer science is one component of it. We develop these systems and devices that you can interface with to explore a virtual world. But it comes with a lot of other questions, especially about human perception.  



Bridging the gap between two communities can also be where the best ideas come from. I believe that a lot of interesting research comes from learning about other kinds of science and seeing how those might be applied to your discipline. As a computer scientist, I may try looking at my problems from the perspective of a different type of scientist, like a human vision scientist. If youre facing challenges, youre probably on the right track.  





What piece of advice do you wish you’d been given when you were younger? 



I wish someone told me earlier on that a PhD can be fun. Becoming a scientist should be fun, and it often is. Sure, it’ll be difficult and you’ll have to work hard, but you get paid to study whatever you think is interesting. Your only real responsibility is to think deeply about that problem or topic and try to contribute some new piece of knowledge. It’s a unique experience that is not the same as just doing more school. It’s very independent. You get to think for yourself and maybe get to know yourself better.  



I also wish someone told me early on that being a scientist is a real career path. Scientists are not just fictional characters in movies. Were real. 

Hey friends. So, this is book club part 2. Today, I’m going to be announcing the title as well as getting y’all’s opinions on the first few paragraphs of this book. ok, so the title of this book will be, ”Lucy’s busy life.” Credit to Messel for helping me choose a title! So now, all […]

Every big planet begins with a pebble.



Okay, not just one. It starts with lots of pebbles a flat sea of them stretching perhaps hundreds of times wider than the distance from Earth to the sun. Their sizes vary greatly. Some may be mere dust particles. Others may be small to fairly substantial rocks.



Explainer: What is a planet?



These pebbles tumble violently within the gassy disk encircling a young star. Lurking within that disk are the ingredients not only for planets, but also for asteroids, comets and living things. What they become depends not only on those ingredients, but also on their location and the temperature of the gas. 





Like fussy chefs in a kitchen, astronomers today debate over how much of which ingredients must have been present in that early solar system. And when. And how they might have interacted and combined. And what would happen if you changed their temperature.



We all know how the planet-making process ends. It produces rocky worlds like Earth, Mars and Venus. It also leads to gas giants like Saturn and ice giants like Uranus. Outside the solar system, the planetary zoo includes stranger worlds. Scientists have spotted a world that they first thought was made of diamond but now believe has oceans flowing with lava. Theyve observed a hot gas giant where drops of iron probably fall like rain and a small hot planet enshrouded in steam.



An artists interpretation of a binary star system, with a surrounding ring (in brown) that might give rise to a rocky, Mars-sized planet. JPL-Caltech/NASA



But how disks of gas and rocks become planet factories is still under debate. The beginnings where dust grains barely micrometers (a few ten-thousandths of an inch) across stick together to form rocky solids isnt too controversial. And thanks to powerful telescopes, researchers have ideas for how planets move once theyre fully-formed.



But in-between is a doozy. For centuries, scientists have been testing and fighting over ideas about how to connect the beginning to the end. Most of the seemingly best ideas have run into problems.



Over the last 10 years or so, however, a process called pebble accretion (Ah-KREE-shun) has gained popularity. Accretion refers to somethings gradual growth. This occurs as new bits of material join something or glom onto it. In this case, its a swirling disk of gas and pebbles that clump together to form a family of planets.



According to the theory, tiny rocks in the disk slow and heat up as they fly through the gas near a larger rock. Its a phenomenon similar to how water in a pond slows a sinking rock. These flying pebbles eventually spiral down to land on the surface of larger rocks nearby. Pebble by pebble, a giant planet is born. And compared to the age of the universe, its a fast process, only taking a few million years.



Pebble accretion really did revolutionize the way that people thought about planet formation, says Katherine Kretke. Shes an astrophysicist at the Southwest Research Institute in Boulder, Colo.



This theory would solve many of the riddles that challenged previous ideas. For example, says Seth Jacobson, It is really the only mechanism that comes close to explaining how Uranus and Neptune formed. Jacobson is an astrophysicist at Michigan State University in East Lansing.



Explainer: Stars and their families



Planet accretion also has gotten a boost from recent studies of distant stars. Observations by the largest radio telescope network in the world, perched on a lonely desert mountain in Chile, match up with some of this theorys unusual predictions.



Anders Johansen, an astronomer at Lund Observatory, in Sweden, knows a lot about pebble accretion. He has been one of the leading researchers arguing in its favor. Puzzling out how it might work consumes his days.



He compares studying the origins of planets to working through a detective story. The solar system provides clues in the planets we know, he says. Exoplanets beyond the solar system provide more clues. Scientists have to connect those clues to piece together the whole story.



It is just so much fun to work on this, he says.



The planet-making process has produced an incredible variety of worlds, such as these seven exoplanets that orbit the star TRAPPIST-1. JPL-Caltech/NASA



In the beginning



Ancient Greek philosophers believed that planets formed from the chaos that filled the universe. In the 17th century, French scientist and philosopher Ren Descartes suggested that every star sat at the center of a swirling vortex. Planets, made of darker stuff, rested in concentric bands that circled the star.



In the 18th century, a Swedish mystic named Emanuel Swedenborg proposed a different idea. He described planet formation in a way thats closer to modern ideas. The whole thing begins, he said, when the crusty shell around a star explodes. It crumbles. The debris settles into a giant ring encircling that star at its center. Material in that ring eventually clumps into what will become planets. The idea that the planets formed from a swirling cloud of star stuff is called the nebular hypothesis. 





That remains the backbone of ideas today. It also has led to the creation of a long list of new words. Dust doesnt refer to the stuff in your house that mix of dead skin cells, bits of cobwebs, dirt and more. Its the tiny particles too small to see with the eye. When scientists say pebble, they mean small rocks from about the size of a dime up to the size of a sled. They also talk about planetesimals (Plaa-neh-TES-ih muls). These are space rocks that might be as big as a city. Then there are protoplanets, a planet thats almost done forming. 



As scientists have hashed out the details, theyve also run into challenges. One idea popular in the 20th century, for example, proposed that planets formed from the collisions between ever-bigger rocks.



This is an artists depiction of a pebble-ridden disk surrounding the star Fomalhaut, 22 light-years from Earth. Data suggest this disk has begun separating from its sun as it dust (pebbles) have fallen onto inner planets. Larger giant plants imagined near the edge of the disk. David A. Hardy/astroart.org



That explanation, too, starts with a disk of gas and dust, notes Alessandro Morbidelli. Then the dust sticks together to form planetesimals the size of asteroids and comets. Morbidelli is a planetary scientist at the Cote dAzur Observatory in Nice, France. Just forget about the dust, he says. Then, you produce protoplanets by colliding those planetesimals with each other.



This process may sound reasonable. However, Morbidelli also believes thats almost impossible. For one thing, planets that form far from the sun grow slowly. Worlds like Jupiter and Saturn would need tens of millions of years to get so big through smash-ups. But the dust and gas disk from which they were to form only stuck around a few million years. It seems difficult by this process to grow the cores of these planets within the lifetime of the disk, he argues.



Another problem: That model requires planetesimals to collide by crossing orbits. You have all these collisions, all this debris, says Jacobson. The current planets dont look anything like that. We have very nice orbits, almost circular. They dont look like they came from a violent, messy process.



Finally, collisions between big objects dont always produce bigger objects. Its easy to check this one: Just try smashing one stone into another.



If you take two fist-sized rocks, theres no velocity at which you can bring them together and they will stick, says Jacobson. So collisions alone, he argues, cant explain how planetesimals form.



As seen in this artists illustration of the solar system (not to scale), the planets in our solar system travel roughly circular paths around the sun. But scientists know that no orbit is perfectly circular, and some veer closer and farther from the sun during their journey. MARK GARLICK/SCIENCE PHOTO LIBRARY



Paying attention to pebbles



In 2010, two astrophysicists at the Max Planck Institute for Astronomy in Heidelberg, Germany, found a workaround. The answer, they suggested, was in the disks gas. As it moves through a fluid, a solid object slows and heats up. This is due to a force called drag. Because of drag, you need more effort to walk through water than to walk through air. The drag from gas in a disk would likely slow down the pebbles.



This idea became known as pebble accretion with a study published two years later by Johansen and Michiel Lambrechts, another astronomer at Lund Observatory. They used computer models to test their ideas. In parts of the disk having the right temperatures, those pebbles can slow enough, they found, to spiral down to the surface of a planetesimal. From there theyd stay put.



It is a really efficient process, says Kretke. If you have a ton of these pebbles around at the right size, she says, then boom! You can form a planet.



Two big objects spinning through space have only a small chance of colliding. But for one big object streaming through an ocean of pebbles and dust, a collision is likely. With pebble accretion, a planet can grow as big as Neptune or Uranus during the short lifespan of the gas disk. It doesnt need giant outer-space smashups of asteroids and comets to form. And once a planet like Jupiter has a big core, its gravity can attract the lighter elements to jacket it in a thick atmosphere of hydrogen and helium.





The project Disk Detective is recruiting citizen scientists to examine NASA data on their computers and phones. Theyll be hunting dusty debris disks that may mark the birthplaces of new planets.



Pebble accretion does a good job of explaining how big planets form, says Morbidelli. It also suggests that the gas and dust in a disk determine what type of planet forms near a star or if a planet forms at all.



Or maybe it doesnt have to be a smooth disk. With pebble accretion, planets may form from misshapen rings of dust and gas that swirl around a star. In 2018, scientists studied some gas and dust orbiting stars. They used the largest radio telescope network in the world, called ALMA. (The name stands for Atacama Large Millimeter Array.) This group of giant, silvery dishes peer into space from atop a desert mountain in Chiles Atacama Desert.



What they found was shocking. Some stars have rings of dust and gas not disks. Others have large disks, or small disks. And not all rings were smooth. Some had regions where the dust and gas got stuck and clumped. Other regions seemed sparse.



We saw such diversity at the disk level, says Morbidelli.



The challenge now, he says, is to use pebble accretion to connect those ring structures to planets that may emerge.



Problems in pebbleland



Most astronomers agree that pebble accretion is a good explanation for how big planets form. Nobody questions that, says Morbidelli. But the complete explanation of how planets form is likely much more complex. Getting pebble accretion to produce planets, even in models, requires other parameters to be just right, he cautions.



For instance, pebble accretion requires a bigger rock onto which the smaller pebbles land. So we still need collisions of planetesimals to create moon-sized objects before pebble accretion takes over, he suspects. Disks must also exist filled with plenty of matter to supply all those pebbles. ALMAs observations suggest such giant disks can exist. But scientists are still collecting evidence to prove that.



Johansen and others also caution that pebble accretion likely falls short of explaining the whole story. A study published this past February showed how planetesimal collisions could have produced Jupiter, no pebble accretion needed. Gennaro DAngelo at Los Alamos National Laboratory in New Mexico and his colleagues authored the work. Their new paper doesnt rule out pebble accretion; it just shows that it may not be the only explanation for planets. Scientists still need to explore other possibilities.



Pebble accretion may not explain the formation of all planets. One recent study, for instance, showed that the planet Jupiter could have formed from collisions of planetisimals no pebble accretion required.Image data: NASA/JPL-Caltech/SwRI/MSSS; Image processing: Tanya Oleksuik (CC BY-NC-SA 2.0)



And they are. In a paper published in 2018, scientists combined planets and planetesimals in a kind of hybrid scenario.



Pebble accretion helps explain conditions under which big planets can form, DAngelo says. But that process depends on getting the timing and temperature just right. Without that, the pebbles might drift too quickly through the disk, he says, and the growing planet might not have time to accrete them.



Plus, theres a Goldilocks issue with pebble accretion. The planet-growing time has to last long enough to allow a stream of pebbles to land onto the core. But observations of other systems show that disks dont last forever. They often last only a few million years. And that puts a deadline on planet formation. So a planet cant grow too fast or too slow or it wont form at all.



Can pebbles lead to Earths?



Another lingering question about pebble accretion is whether it can form small, rocky worlds such as Earth and Mars.



Johansen thinks it can. In a February paper in Science Advances, he and his colleagues describe a model that shows how a stream of pebbles might do this. Pebbles collect on planetesimals at about the same distance from the sun as Mars is today. After the planets form, they migrate or drift over time into their current positions.





Computer simulations allow researchers to visualize how planetesimals formed, giving rise to planets, billions of years ago. Later, these visualizations suggest the neighborhood temporarily got very violent as the giant outer planets changed their orbits, wreaking tumult everywhere.



Morbidelli has his doubts. Personally, I think that somehow the giant planets grew by pebble accretion. But the terrestrial [rocky] plants, he believes, were mostly immune. Jupiter is the solar systems oldest planet. And as it grew, it blocked the flow of pebbles toward the inner solar system. That would have left no more pebbles to build the rocky planets. The solar systems inner planets, including Earth, could instead have formed through big collisions, he suspects.



Finding a way for planets to form is only the first step, says Kretke. The next question is, do we actually have a situation where pebble accretion dominates the process? In our solar system, or some other planetary system?



Scientists need better evidence before anyone declares pebble accretion to be the main planet-forming process in the cosmos. But given the wild diversity of planets both close to home and far away, he suspects scientists will find a range of explanations.



The physics is not different from here to there, he says, But the planets and the processes will depend on the conditions where they form.



Understanding those processes, says Johanson, promises two major rewards. First, scientists could understand each step in how to make a world, from dust to planet. Second, such studies could help point out where to look for life beyond the solar system.



If we want to understand habitable exoplanets, he says, we have to understand our own habitable planet.

Flights are the fastest way to get around. But did you know that a long-distance trip produces more carbon pollution than citizens of some countries produce in an entire year? Since flights are a big part of our lives, JetWind, a Texas-based company has been working on harnessing wind energy generated by aircraft. The company has demonstrated the ability to produce 65 megawatt-hours of clean energy annually from just one bank of its energy-capturing pods! This new technology has already attracted the attention of numerous countries including the United Kingdom, France, Australia, Brazil,...

Do you have a pet dog? If you do, Im pretty sure youve already wondered about how old your pet is in dog years.  While we measure our age in years, dogs age a bit differently. But before I explain how this works, I want to talk about a common myth that isn’t true. Many […]

On February 19, 2026, American figure skater Alysa Liu delivered a flawless routine to win the womens individual title at the Milano Cortina Winter Olympics. Her victory ended a 24-year gold medal drought in the event for the United States (US). The last American woman to win was Sarah Hughes in 2002.

WhenJennifer Johnsonand her team embarked on theirannual quest to survey the sturgeon population in the Detroit River in mid-April 2021, they had fully expected to find some super-sized specimens.However, theU.S. Fish and Wildlife Service biologists had never anticipated luring in thegranddaddy of all sturgeons a massive, 240-pound, 6-foot, 10-inch long fishthat they estimate is at least a century old!