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[scienceguy22]

The pill bug's titanic cousin—the ocean's most patient predator.

A pill bug is a tiny land-dwelling crustacean that looks like a miniature armored tank & can roll into a ball, usually a small, gray, oval creature, about 1/2 in (1-1.5 cm) long, that lives in damp soil, under logs, rocks & leaf litter. These small crustaceans (called isopods) are related to the giant isopods in the ocean. Both share a segmented, armored exoskeleton, usually 14 legs, a flattened body shape & similar ancestry. Bathynomus is a deep-sea giant that lives in the dark, deep ocean about 900 meters (2,950 feet) below the surface. It can grow larger than a football (11 inches/28 cm), but depending on the species, it can reach 30-50 cm (12-20 in) in length, weighing several pounds. There's hardly any food down there because at 900 m depth, there's no sunlight, & food arrives only as tiny falling debris known as "marine snow." As a result, some isopods have to go 5 years without eating. How?

Supergiant isopods have a massively enlarged stomach taking up 2/3 of their body cavity. This lets them gorge when food is scarce. They can store huge amounts of nutrients. One captive individual ate 5.7 lb (2.6 kg) of food in one sitting. Eating that much food in one sitting is like a human suddenly eating their entire body weight in a single meal. It's biologically impossible for us but normal for a supergiant isopod. The isopods eat any large organic debris that sinks, as well as dead fish, whale carcasses & squid remains. They're basically the cleanup crew of the deep sea. They have an extremely slow metabolism in the deep, cold seawater. This means they can burn energy very slowly; they can stretch stored nutrients for years—their organs operate in "low-power mode."

They also have evolved a gene called nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1). The gene converts nutrients into usable energy, ATP (adenosine triphosphate)—the primary energy-carrying molecule in cells—controls how efficiently cells extract energy & regulates energy flow during starvation or stress. The fact that they have the ND1 gene is highly unusual because they didn't inherit the gene from their parents; rather, they picked up the gene from bacteria, known as horizontal gene transfer (DNA moving sideways between different species instead of down the family tree). The isopod borrowed a tiny piece of "survival software" from bacteria millions of years ago, installed it into its own DNA, & now uses that bacterial tool to conserve energy in the deep sea.

Bacteria are masters of surviving harsh conditions such as low-oxygen environments, low nutrients, extreme cold & high pressure. The deep sea is exactly like that. So the isopod's bacterial ND1 gene helps it extract more energy from tiny bits of food, run its metabolism slowly, survive years without eating, & stay alive in cold, oxygen-poor water. This gene is the main reason they could go 5 years without eating. That's like a human suddenly having a gene from yogurt bacteria.

Most animals that can survive that long without eating do so by freezing (tardigrades), drying out (brine shrimp), sleeping, or becoming inactive (lungfish, some frogs). Tardigrades can survive 30+ years without eating, but they dry out almost completely, curl into a tiny ball, shut down metabolism to 0.01% of normal, & become virtually indestructible. But they are not living normally during this period called a "tun"—they are in a paused life mode, like hitting "freeze" on a movie. The supergiant isopod does none of these. It remains alive, awake, moving, functional, capable of scavenging & capable of reproduction—all while eating nothing for years. This makes it the longest active fast known.

[scienceguy22]

Chemical birth control, mole-rat style.

A naked mole-rat queen produces one special oily chemical, isopropyl myristate, found only on her skin. Other females smell it. That smell switches their reproductive hormones, making them infertile. Scientists expected a complicated mix of pheromones, like bees, but instead found one single molecule doing the entire job. Unlike bees, naked mole rats are born with working ovaries. They're fully capable of becoming queens, but the queen's scent keeps them shut down. If the queen dies or disappears, the smell fades, & suddenly several females begin producing hormones again. They fight, and one becomes the new queen. With bees, worker bees do have ovaries, but they are tiny, underdeveloped, & normally switched off by the queen's pheromones. When the queen bee is present, workers cannot reproduce; when she is gone, some workers' ovaries reactivate, but they can lay male eggs only.

Naked mole rats are very interesting rodents. They are one of the strangest mammals ever studied: they barely age, resist cancer, survive without oxygen for extended periods (up to 20 minutes), feel little pain, live like ants with a queen, communicate in dialects & break almost every rule of mammalian biology. They live over 30-37 years, which is astonishing for an animal the size of such a small hamster. They're 3-4 in (7.5-10 cm) long, weighing 1-1.5 oz (30-45 g). This is far longer than a mouse or hamster (2-4 years). They are one of the longest-lived rodents known. Their bodies show almost no signs of aging: stable metabolism, strong protein control & an unusually robust immune system. They are essentially immune to spontaneous cancer. They rarely develop cancer. A key mechanism is high-molecular-mass hyaluron, basically extra-thick, super-stretchy body jelly that protects naked mole-rat cells from crowding & turning cancerous.

They have evolved pain insensitivity to acid & capsaicin-like stimuli (the hot chemical in hot peppers). This helps them survive in underground tunnels filled with CO₂, which forms carbonic acid, a mild acid. They can survive for 20 minutes without oxygen because, like plants, they change their metabolism to fructose when oxygen in their tunnels disappears. Their metabolic switching shields them from heart damage during oxygen deprivation. Oxygen disappears in tunnels because they live 6-12 ft underground (2-4 m) in huge, crowded mazes only 1-2 inches wide (2-5 cm) without almost any airflow, just enough for one rat at a time. A colony can have 20-300 mole rats, so every breath they take uses oxygen & adds CO₂. In a tight tunnel, this quickly changes air composition.

They're "naked" because they lack fur, which would be useless—and even dangerous—in a cramped, hot, abrasive underground world. They look like they've been through a wringer because their skin is built for scraping against dirt all day. They cannot regulate their body temperature like most mammals. They behave more like cold-blooded reptiles, huddling, moving to warm tunnels, or relying on colony heat.

Naked mole rats have 4 huge front teeth that stick out like Bugs Bunny. These teeth are so important that 1/4 of all their jaw muscles attach directly to them. They use them to dig huge tunnels that can stretch 2-3 mi (3-5 km) & reach 2 meters (6.5 ft) deep. They use their incisors for carrying food & objects, fighting & grooming, picking up bedding, moving pups, & defending the queen. They can move their incisors independently like chopsticks. These tunnels are not straight lines—they're branching mazes with food-searching corridors, nursery chambers, sleeping chambers, waste chambers, emergency escape routes, & the queen-centered royal chambers.

One of the few eusocial mammals (a high degree of social organization in which a single female produces offspring and nonreproductive individuals care for the young) is the naked mole rat. Workers dig tunnels & gather food; soldiers defend the colony from snakes; everyone cooperates like a living machine. In short, they're mammals that live like a hive.

Colonies that live together have distinct vocal dialects—essentially "accents." Workers learn their colony's dialect from the queen & use it to identify members. Studies show their brains resist aging, maintaining a youthful neural function for decades, with minimal neurodegeneration.

[scienceguy22]

The parasite behind the "explosive diarrhea" headlines.

The parasite is called Cyclospora cayetanensis, a microscopic parasite (a protozoan known as a coccidian). It infects the small intestine & causes watery, explosive diarrhea. The outbreak is linked to imported produce, especially shredded lettuce from Mexico supplied by Taylor Farms de Mexico to Taco Bell restaurants in at least 5 U.S. states. Taylor Farms has now pulled the product. This cyclosporiasis outbreak has already become the largest in U.S. history, with thousands of cases counted by individual states, with Michigan having the highest number at 2,640 as of July 13. It's hard to say exactly how many cases there are, because there's a 6-week lag between the time the illness begins & it is reported to federal health authorities. Other types of Cyclospora have been found in baboons, cats, vipers, moles, rodents & even millipedes & centipedes. But C. cayettanesis only infects humans.

It is spread through human feces, & people get it either by eating contaminated food or drinking contaminated water. Once you swallow their eggs, called "oocytes," they take over your gut. They lay their eggs in the intestinal wall, which you expel when you poop. Other than lettuce, other foods associated with the disease are raspberries, basil, cilantro & snow peas, but any raw produce can be contaminated if grown or washed with unsafe water, including pre-cut fruit mixes. The only way to kill the parasite is to cook the food at 160°F (71°C). Freezing or washing will not kill it. As for leafy greens like lettuce, avoid buying bagged or pre-mixed salad; instead, buy a whole head of lettuce & throw away the first few layers of leaves. Symptoms include nausea, fatigue, stomach cramps, gas, loss of appetite, low-grade fever, bloating, & frequent & sometimes explosive bowel movements. Unfortunately, cyclospora-caused diarrhea can last for weeks & sometimes even longer than a month.

A person I know is currently on day 5 of running to the bathroom over 40 times a day, and nothing is solid. The dangers include severe dehydration, electrolyte imbalance & weight loss. Now for some good news: a Cyclospora infection can be treated by a 10-day course of antibiotics such as Bactrim or Septra. Most people's symptoms resolve within a week. It is not life-threatening for most people but can cause severe illness in younger or older people, as well as those with weakened immune systems. Even during this outbreak, you really don't have to avoid eating fruits & veg. They're essential for heart health, gut health, immune function & longevity. Avoiding them entirely would cause more harm than the outbreak risk.

If you're worried, you can always eat whole fruits with peels (bananas, citrus fruits, pineapples, mangoes, papayas, melons, but wash before cutting & avocados); grapes grown off the ground; apples; pears; cherries; blueberries; plums; peaches & nectarines, which pose a lower contamination risk; & cooked vegetables. Many of these fruits are peelable. Cyclospora contaminates surfaces. If you peel the surface off, the parasite is gone, but make sure you wash your hands well with soap & hot water. Frozen vegetables are very safe because they're blanched before freezing. Canned fruits/veg are extremely safe because canning involves high heat. Any whole vegetables you cook yourself is safe. The outbreak is highly specific—tied to one crop from one farm or one supplier.

[scienceguy22]

Announcement.

It's that time again when I'm scheduled to give a lecture to the public, this time on "The body and the mind." But I'll be back again tomorrow, same time, same place, with you all. Until then, this is Peter, scienceguy22, hoping all the chemistry in your life comes out just right.

[scienceguy22]

A robot dog that actually handles the real world.

It's a robot dog called Kaist Hound that was trained using reinforcement learning to use 2 pre-learned gaits: trot-stable, careful, and good for stairs or uneven ground. 2. Bound-fast and springy, good for clearing obstacles like logs, which it can easily bound over. It sees the world with laser scanning to measure distances & terrain height, as well as cameras to see shapes, edges, & obstacles. Instead of waiting for a human to tell it what to do, the robot dog scans the terrain, predicts what movement is safest & switches gaits instantly. This is the breakthrough: real-time autonomous adaptation. It weighs 100 lb (45 kg). That's the weight of a medium-large dog, but with far more strength & stability.

It's a breakthrough also because most robots fail in real terrain. They struggle with stairs, forest debris, rocks, logs, slopes & loose soil. It can go in dangerous terrain and can go where humans shouldn't. It's fast to train. It's a foundation for future robots. It's likely to be used in search & rescue, industrial inspection, military reconnaissance & environmental monitoring.

[scienceguy22]

Nope, the Swedish crows are off duty—Sweden says they never hired the birds to clean up discarded cigarette butts.

A behavioral scientist did propose an idea in 2022 to train wild crows in Sweden to pick up cigarette butts & drop them into special machines that would reward them with food, but the city never approved or implemented the project. There's no doubt that crows are famously intelligent—capable of counting, recognizing faces & using tools—so people found it believable. Their problem-solving, memory, & reasoning skills often fall in the range of a 3-5-year-old child. Crows can remember human faces for years across seasons. A crow's brain is only about the size of a walnut, but it has extremely dense neurons; its forebrain functions like a mammalian prefrontal cortex, so it packs a lot of power into 3 oz (85 g).

A Science Week demonstration in 2022 showed the concept of crow cleanup crews for cigarette butts, & a startup called Colrvid Cleaning pitched the idea. Social media amplified the claim until it looked like an official Swedish program. Although Sweden never did this, in 2018 a French historical theme park used trained birds to pick up cigarette butts. This only highlights that cigarette butt filters are one of the most common, most toxic, & most environmentally persistent forms of litter on Earth. They're everywhere; they don't biodegrade & they leach chemicals into soil & water. The fact that people even imagined outsourcing cleanup to birds shows how badly humans are failing at managing this waste stream. Globally, 4.5 trillion cigarette butts are discarded each year. That's enough to fill hundreds of Olympic swimming pools. They're the #1 most littered item on Earth—more common than plastic bags, bottles, or straws.

Filters are plastic, not cotton. They leak nicotine, arsenic, lead, cadmium, polyaromatic hydrocarbons, volatile organic chemicals & tar residues into soil, lakes, rivers, & beaches. A single butt can contaminate 1-2 gallons (4-8 L) of water to harm aquatic life. Wildlife mistake them for food. We need better waste management & better human behavior, not birds.

[scienceguy22]

Urea's $700-per-ton shockwave—the perfect storm. From missing urea to missing meals.

People around the world are cutting back on foods simply because they have become too expensive. Why? Because of a lack of fertilizer whose main component is nitrogen, which is sourced from urea. The cause is the ongoing blockage of the Strait of Hormuz by both the Iranians and now the United States. Almost nothing is passing through that typically delivers natural gas (LNG), oil, & fertilizer to nations all over the world. Hormuz handles only 10-20% of global fertilizer/energy, but losing that 10-20% creates a global shortage because the remaining 80-90% cannot be redirected, expanded, or substituted fast enough—and because prices are set at the margin, not by averages. In global commodities, the last 10-20% of supply, the most flexible exporters, & the most accessible shipping routes are the ones that set the global price. The market loses its "shock absorber," so prices spike for everyone even if most supply still exists. This is why oil can jump when only 5-10% of supply is threatened.

That 10-20% of energy & fertilizer that stopped transiting through Hormuz has caused 30-60% price increases across the board. It's resulted in panic buying, hoarding, export restrictions, freight cost inflation & insurance premium hikes. The lack of urea fertilizer has made food items 40% to over 100% higher. Examples are bread (40-80% higher), coffee (40-100% higher), jams & frozen berries (50-100% higher), milk (40-60% higher), chocolate (40-100% higher), chicken (40-70% higher), tomatoes & peppers (40-100% higher), apples (50-100% higher), mushrooms (40-80% higher), eggs (40-100% higher), yogurt (40-70% higher), toilet paper (40-60% higher), & even condoms are 40-100% higher. (I'll get to that a little later).

In 1828, noted German chemist Friedrich Wöhler excitedly wrote to his former teacher Jan Jacob Berzelius that "he was able to make urea without the need for a kidney, whether of man or dog." Urea is the world's most widely used fertilizer, containing 46% by weight, which, along with potassium & phosphorus, is essential for plant growth. You can see the 3 elements on fertilizer bags marked by an N (nitrogen), P (phosphorus), & K (potassium). Urea is water-soluble & can be spread on soil, & then microbes break it down. The breakdown products are the ammonium ions & the nitrate ions that plants use directly to produce chlorophyll, proteins, DNA, & other chemicals. The Hormuz stoppage connection is that Qatar is the major producer of urea, but its ships can't pass through the Strait. The closure of the Strait will result in higher prices for farmers and, ultimately, for us.

Friedrich Wöhler was excited not because he thought urea was an essential fertilizer; in 1828 urea had no practical use. 100 years would pass before its ability to furnish usable nitrogen for plants was discovered & a commercially viable method for producing it was developed. No, Wöhler's jubilation came from his discovery that he could make a synthetic compound (ammonium cyanate) identical to the natural chemical urea. Before this, the common scientific belief was that natural substances contained a "vital force" that could not be replicated through synthetic means. This moment is widely considered the birth of modern organic chemistry.

Today we use the Haber-Bosch process, invented in 1909 by chemists Fritz Haber & Carl Bosch, which takes natural gas (methane), strips out the hydrogen, mixes it with nitrogen from the air, & squeezes them together at insanely high pressure (150-300 atmospheres). That's 150x the pressure inside a car tire, or like 300 elephants standing on every square inch of your body. Then it's all heated to 800-900°F (425-480°C), which reacts to form ammonia. Ammonia is the main ingredient for urea.

Both the hydrogen & the energy needed are supplied by natural gas, which can combine with steam to yield hydrogen & CO₂. This requires a lot of energy, which means burning fossil fuels, which also releases CO₂ to run energy-intensive reactors. Producing 1 ton of urea emits roughly 0.6-1.0 tons of CO₂ from energy use plus additional CO₂ from natural gas reforming, making this environmentally unfriendly. Qatar has plenty of natural gas but can't ship it out. Pakistan and Bangladesh both make fertilizer, but they do so using natural gas, which comes from the closed Persian Gulf. So some plants in Pakistan & Bangladesh have already shut down.

It is possible to make what's known as "green ammonia" without having to resort to natural gas as a source of hydrogen. Water can be split into hydrogen & oxygen by passing electricity through it, but to be "green," that electricity has to be produced from solar, wind, or water power (Hydro), not fossil fuels. The hydrogen that's produced from this "green" process pulls nitrogen from the air that is combined with hydrogen from water that is then converted to ammonia & then into urea. But most countries don't produce electricity from green sources to do this. They have to burn fossil fuels. Adding to all of this is that many edible crops like wheat & corn are being turned into ethanol that's added to gasoline at around 10%. Europe alone converts enough wheat into automotive ethanol every day to equal the grain content of about 15 million loaves of bread. That could feed a lot of tummies.

Any industry that requires energy is affected by the Iran war, & believe it or not, that goes for condoms too. Malaysia's Karex Company is the world's largest producer of condoms, turning out about 5 billion a year. About 85% of them are made from natural latex, but to turn this into rubber, manufacturers must "vulcanize" it, which is a heat-intensive method. The energy for vulcanization comes from burning oil, gas, or coal, especially in Malaysia. Because oil & gas prices have spiked—as they did when Hormuz was disrupted—condom prices shot up 40-100%.

When tanker traffic dropped from 129 ships/day to under 10, energy prices surged. This has affected everything, including plastics & condoms. Higher condom prices mean lower usage, resulting in higher pregnancies. This has been observed in South Asia, Latin America, Africa, and even parts of Europe during supply shocks. More babies mean more mouths to feed, more food demand, and more fertilizer demand. more oil demand & consequently more wars.

[scienceguy22]

Trapdoor genitals: the secret hatch.

Daddy longlegs are what many people think are spiders, but they're not. Spiders come from the order Araneae, while daddy longlegs derive from the order Opiliones. Yes, they are arachnids, but as different from spiders as crabs are from insects. Spiders usually have 8 eyes because they rely heavily on vision. Daddy longlegs have only 2 tiny eyes, placed on a little bump called an ocularium. They cannot see detail, color, or distance. So they rely on other senses far more. For example, their legs are packed with hairs, vibration detectors, & chemical receptors. Each long leg is a cane, a radar dish, a smell detector & a vibration detector. Their legs are 2-4 inches long (50-100 mm), while their body is only 0.1-0.4 in. (3-10 mm). That's like a human with 20-foot legs (6 m) being used as a giant sensory tool. Their legs can detect footsteps, wing beats, crawling insects & approaching predators, letting them "feel" danger before it strikes them.

Daddy longlegs smell through chemoreceptors on their legs & mouthparts. They can detect rotting plant matter, dead insects, fungi, moist areas, & other harvestmen. They're essentially like a blind person using canes, & when they touch something edible, they grab it. Their poor eyesight matters even less at night. Their sensory legs work just as well in darkness. They're called "Daddy," because in the 1600s-1800s, rural English speakers used family roles to describe animals, so "Grandaddy" was the name for big beetles, "old man" for slow creatures, and "Mother Carey's chickens" for storm petrels. None of those names stuck except for daddy longlegs. Daddy longlegs have external genital openings located on the underside of the body, near the front. Their genitals are hidden because they have a trapdoor genital plate, a hinged cover—literally a little door covering their genital opening. It protects delicate tissue, prevents it from drying out & opens only during mating.

Unusually for arachnids, males have a penis. The male inserts his penis into the female's genital opening once her trapdoor plate lifts. Sperm is delivered directly. Spiders do not; they use leg-like structures called pedipalps to transfer sperm. Female daddy longlegs have an ovipositor, a tube-like structure used to place eggs into soil, leaf litter, bark crevices, or moist cracks. Daddy longlegs cannot make silk like spiders do, so they make no webs & no cocoons. Daddy longlegs walk everywhere & rely on stealth, scavenging, & their long legs to explore safely. Daddy longlegs cannot bite you in any meaningful way. They also do not possess venom. If they are captured, usually by their long legs, they have a neat trick. They can drop a leg, popping off neatly. And the dropped leg continues twitching for minutes, distracting predators. This is like a lizard dropping its tail.

They defend themselves by vibrating rapidly (blurring their outline). And they release a smelly chemical from glands near their legs that discourages predators. They are often found clumping with thousands of other daddy longlegs. The benefits of clumping with thousands of others are shared vibration detection, shared airflow sensing, & confusing predators with a mass of moving legs. If they lose one or two legs, they can still walk, albeit more clumsily. Should they lose 3 or 4, they would struggle to balance, but losing all legs is a death sentence. Daddy longlegs have been around for 405 million years, older than dinosaurs, spiders, flowering plants, & most modern insects. They walked the Earth when it was covered in ferns & early forests. They eat dead insects, sip plant juices, consume fungi, & occasionally hunt tiny prey. They're essentially ecological cleaners.

Their brain is extremely small—more like a cluster of nerve cells. Most of their "thinking" happens in their legs. Some daddy longlegs guard their eggs, a rare behavior in arachnids. They stand over them & fend off predators.

[scienceguy22]

Space sugar: The raspberry molecule among the stars.

Scientists have just found a sugar molecule in a giant molecular cloud called G+0.693-0.027, located near the center of the Milky Way. The sugar is called erythrulose, & on Earth it's also found in raspberries, fermented foods, some bacteria, & in cosmetics, especially self-tanners, because it reacts with skin proteins to create a browning effect. By itself, erythrulose is barely sweet. It's only 10-20% as sweet as sucrose. So if a teaspoon of sugar (4 g) tastes "normal," you'd need 5-10 teaspoons of erythrulose to get the same sweetness. But finding the sugar molecule is significant because sugars are essential for life; they are part of RNA, DNA, & cellular metabolism, they're needed for energy storage, & they are key to biochemical reactions. Finding them in space means life's building blocks don't need a planet to form, & they have been delivered to planets, including Earth, by comets & asteroids. The early Earth received huge amounts of organics in what is known as the Late Heavy Bombardment (LHB) between 4.1 and 3.8 billion years ago.

The LHB was frequent (thousands of years), huge & energetic. Explosions were equal to being hit by billions of nuclear bombs. The LHB is basically Earth's worst meteor shower ever. During this bombardment, Earth received water & organic molecules, like sugars, amino acids & alcohols, & created hot pools & chemical environments where life could have begun. If Earth received 0.5 and 50 million tons of erythrulose, that's 1 million to 100 billion pounds or 450,000 to 45 million metric tons. That's enough to coat the Earth with a thin layer of organic molecules. This is the first confirmed detection of erythrulose in the interstellar medium. Before this, scientists had found other sugars such as glycolaldehyde, glyceraldehyde, ribose, erythritol (a sugar alcohol that is also used in low-calorie artificial sweeteners), & other polyols & sugar-like molecules.

If you're wondering whether we could collect & eat the sugars in space, the answer is no, because the sugars are extremely dilute. Even though the interstellar cloud in the Milky Way contains tons overall, they're spread across billions of cubic miles (billions of km²). You'd need astronomical volumes of gas to get a teaspoon. Aside from that, the sugars are mixed with toxic chemicals like cyanides, formaldehyde, methanol, reactive radicals & carbon monoxide.

[scienceguy22]

The meal that waits 50 years to kill you.

We don't have to worry about it. It applies to people who would practice cannibalism. In the 1950s, kuru became the most common cause of death among women in Fore villages of Papua New Guinea. Of the 11,000 people belonging to this Papuan community, around 200 died each year. That's nearly 2 out of every 100 people. In a small community, that's catastrophic. At first, scientists were puzzled why women were dying until they unraveled the gruesome cause. It turned out that when a person from Fore died, their friends & family would cook & eat them. Fore believed that it was better for the body of a loved one to be eaten rather than consumed by maggots & other insects. It sounds gruesome & sick, but for these people, it was an act of love & grief. Women most often died of this disease because it was women who would remove the brain, mix it with ferns, cook it in tubes of bamboo, & ultimately consume it. Sometimes, mothers would also give some to their children. Men often ate different parts or abstained.

Cannibalism was certainly not worth it, especially if the person's brain contained misfolded prions. Prions are proteins in your brain that can exist in two shapes. All mammals have prions, which appear to play a role in memory formation, cell signaling, neuron protection, and tissue maintenance. However, those are normal prions with a normal shape. However, if they are misfolded, it can force other proteins to fold incorrectly as well as kill neurons, build clumps, punch microscopic holes in the brain & always end up killing an infected person. So anyone eating an infected brain with misfolded prions would eventually die.

The body has no effective way to break down or clear misfolded proteins. Once enough damage is done, brain circuits are lost permanently. Bacteria & viruses are normally killed by standard cooking temperatures. But prions remain infectious even after cooking, boiling, oven roasting, pan frying, smoking, dishwashers, & many disinfectants such as bleach. Prions are the most heat-resistant infectious agent known.

Cows used to die from it as well, which caused mad cow disease, or bovine spongiform encephalopathy (BSE). Cows developed BSE after being fed animal-derived protein containing prions. In the 1980s and 1990s, humans who ate infected beef came down with variant Creutzfeldt-Jakob disease. Infected meat came from brain tissue, spinal cord tissue & certain nerve ganglia. Today, this is very rare because of strict regulations that ban brain/spinal cord & organs like the liver & kidney, which are checked for safety. Because it causes tremors and shaking, the Fore people's word "kuru" means "shaking." They become less coordinated and are more likely to laugh or cry uncontrollably and inappropriately. They eventually lose their ability to stand, experience severe muscle atrophy, have trouble swallowing, get infections, and pass away.

Kuru & other prion diseases can incubate for years to decades—sometimes up to 50 years. You can feel perfectly healthy for most of your life after exposure, then suddenly a rapid, fatal, irreversible brain disease ensues. Once the Fore stopped cannibalism by 1965, all new infections stopped instantly. But people who ate infected human brains before 1960 could still develop kuru decades later—and they did. Cases continued into the 1970s, the 1980s & 1990s, with the last known kuru patient dying in 2009. That's 49 years after the practice ended. This shows how insanely long prion incubation can be. Today, the Fore people are healthy, thriving, & no longer at risk.

[scienceguy22]

Modern mummy, ancient methods.

To mummify a modern person in the fashion that ancient Egyptians used, the donor's family gave written permission for his body to be used in a controlled scientific study. The researchers settled on a 76-year-old Caucasian man who died of a heart attack. They nicknamed the man "E. M. Balm." Researchers aimed to replicate Egyptian mummification circa 1250 BCE using only period-accurate materials and the same tools ancient Egyptians used. Following ancient texts, they extracted the brain, which Egyptians believed was useless, through the nasal cavity using hooked bronze instruments. They first tried scooping the brain out using a hooked rod, but the tissue was too soft & wouldn't come out. They finally took to squirting water up E. M. Balm's nose, then used the rod to whisk the brain into a slurry. After that, it poured right out, like a milkshake—a strawberry milkshake, to be precise. Following this, they made a 3 1/2 in. (9 cm) incision in Balm's abdomen & removed the spleen, liver, gallbladder, lungs & 22 feet of intestines.

With organs removed, they cleaned the abdomen with palm wine & myrrh, then stuffed frankincense into the skull. Ancient Egyptians also used pistachio resin, beeswax & castor oil. Ramses the Great had peppercorns shoved up his nose. Next, researchers dehydrated the body using natron (a mineral of equal parts salt & baking soda). This sucks moisture out of flesh, making it essentially jerky. Balm looked just like Ramses the Great, with his skin tightening & shriveling, lips retracting & the skin turning a brownish yellow. His limbs became as stiff as tree branches, & his weight dropped from 188 lb (85 kg) to 79 lb (36 kg). They massaged his body with lotus, cedar, & palm oils, making the mummy easier to handle. His weight dropped after another 3 months to 51 lb (23 kg). He was wrapped in linens.

For the past 3 decades, the mummy has been lying in a metal casket stored at room temperature. They unwrapped him to check on his condition but found nothing amiss. "He's dead and well," they said.

[scienceguy22]

Sharks can do math—seriously.

Bamboo sharks were trained to remember triangles vs. squares, circles, & even different orientations involving visual illusions, like choosing the correct shapes. Even if a triangle was turned sideways, stretched, or partially hidden, they still picked the correct one. Of course, food rewards were the incentive. The amazing thing was that they could do this even after a year. They could do basic math like 3 + 5 or 4 + 7, but not when the numbers were too close, like 4 + 5. That's because the visual difference becomes smaller. In nature, sharks need to know which school of fish is bigger or which coral cluster hides more prey. They only understand visual amounts; the visual difference between 4 and 5 becomes too small for their brain to reliably separate.

Sharks have a taste for jazz but not classical, at least as far as the Port Jackson, Australia, sharks are concerned. It don't mean a thing if it ain't got that swing. Sydney's Macquarie University showed that sharks favored the spot where jazz was being played but were not attracted to the spot where classical music was played. Sharks have belly buttons. Not all but some sharks, like bull sharks & hammerheads, carry their young in their uterus & feed them through an umbilical cord, just like humans., This is why these pups have belly buttons until the scar from the umbilical cord heals. Other sharks neither lay eggs nor raise their pups in their wombs like mammals: the embryos grow in eggs, which hatch while inside the mother. The pups are then born live.

Spiny dogfish gives birth like this with a pregnancy that can last up to 2 years. Sand tiger shark babies eat each other in the womb, each fighting for a chance of survival. Female sand tiger sharks have 2 uteruses, with each containing 5 embryos. The embryos develop teeth early, & the larger embryo starts hunting smaller ones. Only one embryo inside each uterus becomes the sole survivor. After having their fill, the two surviving embryos eat the mother's unfertilized eggs. Sharks also have "besties." They learn skills from each other, & even great white sharks do this. Two named Simon & Jeckyll were seen traveling together for 6,000 km (3,730 miles) without ever separating. Shark skin is covered in tiny "teeth," dermal denticles—tiny, tooth-like structures made of enamel-like material. They're shaped like miniature, teeth-like, rough sandpaper. In the 1600-1700s, Italian luthiers (people who make or repair stringed instruments like violins) used sharkskin as an abrasive to achieve the famous Stradivarius finish. Cabinetmakers used sharkskin as well in Britain's Victorian era. The skins were called shagreen & were made into jewelry boxes, cabinet inlays, knife handles & telescope cases.

Sharks have 3 more senses than we do. In addition to the classic 5, they can detect pressure changes, electric voltage & Earth's magnetic field, giving them one of the most advanced sensory suites of any animal. They can sense your beating heart because they have electroreceptors that sense tiny electrical signals—including the electrical pulse of a beating heart. They can detect signals as small as a billionth of a volt. Sharks see well in low light; they can hear distant splashes from hundreds of feet away. Sharks can detect 1 drop of blood in a swimming pool (roughly 25,000 gallons/95,000 liters).

The earliest fossil evidence for sharks appeared 450 mya based on a collection of scales. That's about 60 million years before Earth's first trees, 220 million years before dinosaurs, 350 million years before Saturn's rings & 380 million years before the birth of the North Star. Humans have only been around for 300,000 years. Modern sharks arrived 195 mya. Sharks survived the "Great Dying"—the Permian-Triassic extinction, which killed 90% of marine life. Humans & sharks share a very distant ancestor from about 440 mya—a small, primitive, jawless fish called an early invertebrate. This creature is the last common ancestor before sharks split off into cartilaginous fishes, & our lineage moved toward bony fishes & eventually land. Our lines may have split all those millions of years ago, but our existence on this Earth is intrinsically linked.

[scienceguy22]

The mouse at the top of the world.

I'm talking about the Andean leaf-eared mouse, which is just 3-4 in (7-10 cm) long and weighs 1-2 oz (30-60 g). Researchers were shocked to see it darting around among rocks at 22,000 feet high (6,700 m). They live where humans need oxygen tanks. Even elite mountaineers struggle at these heights. Oxygen at those lofty heights is only 44% of sea level. Temperatures are almost permanently below freezing. Yet they survive not by entering torpor or hibernating but through genetic & metabolic adaptations. Most mammals at high altitudes rely heavily on carbohydrates, but these little rodents burn fat for energy instead.

This is surprising because fat burning normally requires more oxygen, so it's the last thing you'd expect. Carbs are easier to burn when oxygen is scarce because they give more energy per unit of oxygen, yet these mice burn specialized fats (polyunsaturated fats) (PUFAs)—especially omega-3 & omega-6 fatty acids—which come from the high-altitude plants they eat at extreme altitudes. PUFAs stay fluid & burn well even at -20C (-4F). PUFAs normally require more oxygen to burn, which is why it's surprising the mice use them. However, these mice's extremely effective mitochondria allow them to burn fat even at oxygen concentrations that are only 44% of sea level's. It's one of the most extreme metabolic adaptations ever recorded in a mammal.

They have evolved red blood cell enzyme changes. When oxygen is low, animals breathe faster to get more O₂, but breathing faster also blows off CO₂. Losing too much CO₂ makes blood too alkaline (a problem called alkalosis). These mice have RBC enzyme tweaks that slow down how quickly CO₂ leaves their blood, even when they breathe more. In simple terms: They have a built-in "CO₂ brake" so their blood chemistry stays stable. Through genetic adaptations that enable them to consume toxic plants and other toxins released by neighboring volcanoes, the mice have the surprising ability to detoxify poisonous plants.

[scienceguy22]

Luxury foods: How to build a $666 USD burger without summoning Satan.

The burger cost $666 because it contains gold. The burger was created by NYC chef Franz Aliquo (2012) & was created as a parody of luxury food culture. The burger included a Kobe beef patty, which is by itself the most expensive beef in the world. Why? Because the beef comes from Wagyu cattle in Japan & Wagyu cattle have a genetic mutation that causes extreme intramuscular fat marbling. This fat melts at a lower temperature (77-86°F/25-30°C), giving it a buttery texture. Cattle are massaged, fed special diets, raised in low-stress environments & even given beer (not for flavor but for appetite). True Kobe beef can cost $150-$300 per lb ($330-$660 per kg). Some cuts even exceed $500/lb USD. Caviar is added to the burger, which costs $100-$300/oz ($3,500-$10,000 per kg).

Then the chef added truffles, which, depending on whether they're white or black, can cost $800-$1,500 lb ($1,760-$3,300 per kg) for black & $3,000-$7,000 lb ($6,600-$15,400 per kg) for white. That's not all; Chef Aliquo added foie gras, lobster, Champagne-steamed Gruyere, Himalayan salt & edible gold leaf hammered into sheets 0.1-0.2 microns thick, which is 0.000004 inches to 0.000008 inches, which is like slicing a single hair into 600-1,000 layers. To cover the patty, he used 0.3-1 g (0.01-0.035 oz) of gold. It is completely edible & safe & is excreted in the stool. Critics said it wasn't tasty but would make people "feel rich as fck."

[scienceguy22]

The forgotten 4th laureate, the controversy over credit, and the long road to recognition.

In the early 1950s, scientists were racing to uncover the structure of DNA, the molecule that carries genetic information in every living thing. This discovery would explain how traits are passed from parents to children & revolutionize medicine, genetics, & biology. The key to DNA's double helix structure was unraveled by a crystallographer named Rosalind Franklin, who worked with a graduate student, Raymond Gosling, at King's College in London. Crystallography uses X-ray diffraction to study how atoms are arranged inside crystals. This happens when you have a crystal & shine X-rays on it until the X-rays bounce off in different directions depending on the atoms in the crystal, & by electronic analysis of the data, you can determine the structure that gave rise to that pattern. They refined the technique of photographing DNA fibers using X-rays. In 1952, Gosling captured "Photograph 51" under Franklin's supervision. The image showed a striking X-shaped pattern—proof that DNA was a double helix, two spiraling strands wound around each other.

Think of it like shining a flashlight through lace curtains & seeing the pattern on the wall. The pattern tells you how the lace is woven. Franklin did the same thing with X-rays & DNA fibers. The X-rays scattered off the atoms & made a pattern on the photographic film. It took 51 tries before Franklin & Gosling showed the clearest, most symmetrical X-shaped pattern—proof that DNA is a double helix. That's the reason it's called "Photograph 51." This photograph was the key that revealed DNA's structure to James Watson & Francis Crick, who were working at Cambridge University building models of DNA. When Maurice Wilkins, a British biophysicist who had worked at King's College at the same time as Rosalind Franklin, showed Watson Photograph 51, it gave them the missing clue. They then realized that DNA was made of 2 strands twisted around each other, held together by pairs of chemical bases. Watson & Crick constructed the double helix in 1952, for which the two scientists, along with Wilkins, received the Nobel Prize for Physiology or Medicine in 1962. Wilkins's role was partly as a bridge between the labs of King's College & Cambridge, but there was controversy because he shared Rosalind's photograph without her consent.

Despite Rosalind Franklin's extraordinary skill, she faced skepticism & isolation from male colleagues, including Maurice Wilkins. Their working relationship was tense because of gender bias at the time. In 1953 Watson wrote a whole book about the story of determining the structure of DNA, in which he hardly mentioned Rosalind's name, minimized her contributions & didn't give her much credit, even calling her "Rosy," a name she didn't like. The book caused outrage among scientists who knew her true importance. Although Watson was a brilliant scientist, he also turned out to be a racist & probably a misogynist. Watson claimed that people of African descent were less intelligent—a racist assertion rejected by all credible science. Watson also made sexist remarks about women's roles in science & society. His comments led to widespread condemnation & loss of honors, including a suspension from Cold Spring Harbor Lab, where he had worked for decades. His honorary titles were revoked from several universities, but his Nobel Prize could not be revoked because Nobel rules forbid rescinding awards once they are given. Watson's story shows that scientific greatness cannot protect anyone from the consequences of prejudice.

Rosalind Franklin also deserved to share the Nobel Prize in Physiology & Medicine, but unfortunately, she died at the very young age of 37 from ovarian cancer on April 16, 1958, attributed to her long exposure to X-rays during her crystallography work. The Nobel Prize for the work was awarded in 1962, 4 years after her death, & since the Nobel Prize cannot be awarded posthumously, her estate could not share in the prize. Rosalind Franklin is finally getting the recognition she deserves but never received. Molecular biology and the appreciation of the value that female scientists bring to the world were made possible by her careful research and bravery in a field that was dominated by men. Her name graces institutes, scholarships & even a Mars rover—the Rosalind Franklin Rover, launched by the European Space Agency. Photograph 51 was even launched as a play in London's West End in 2015, starring Nicole Kidman, who portrayed Rosalind Franklin, dramatizing Franklin's struggles & triumphs, bringing her story to a new generation.

She donated her entire salary from the play to charity, including the funding of the Dr. Anthony Kidman Scholarship in Health & Psychology at King's College London, named after her father, a biochemist who worked on similar topics. Franklin's story reminds us that science is not just about discovery—it's about fairness, respect, equality, & collaboration. Rosalind Franklin saw what others couldn't—not just the structure of DNA, but the importance of integrity in science. Her legacy lives on in every genetic discovery made today.

[scienceguy22]

The physics of a 30-ton sexual mount.

How did dinosaurs have sex? We can't be sure, but it was most likely the way birds & crocs do it today. Dinosaurs (like all archosaurs, which include reptiles, birds & pterosaurs) all had a single cloaca—a single external opening used for reproduction, urination & defecation. A beautifully preserved fossil of a Psittacosaurus (parrot-like lizard) shows a bird-like opening, confirming this structure. The male's reproductive organ, similar to a crocodilian penis, entered the female's cloaca. The males have an internal penis that everts during mating. Some dinosaurs had very large tails, but those did not get in the way because tails are highly mobile & could be lifted or swung aside during mating, & even a sauropod with a 40-ft (12 m) tail could raise the base enough to allow cloacal alignment.

For large theropods like T. rex, weighing up to 10 tons (9,000 kg), the male would mount from behind. The female's hips provided a stable platform, & the male had massive, strong legs that allowed bracing. Their tail acted as a counterbalance. They likely chose firm ground, packed sediment & open clearings, mirroring modern elephants & rhinos. All female dinosaurs produced eggs; live births are unheard of. Eggs form inside females' oviducts long before laying. Shells were mineralized with calcium carbonate (CaCO₃). A typical egg was 8-10 in. (20-25 cm) in diameter, & she would lay clutches of dozens. Internal fertilization was required for egg development—another reason cloacal mating is almost certain. Courtship mirrors much of modern birds with visual displays (frills, crests & feathers), vocalizations & territorial posturing, & perhaps small theropods with feathers may have performed elaborate dances similar to modern birds of paradise.

Since reproductive organs are soft tissue, these organs rarely fossilize. Most of what we know comes from bone structure, muscle attachment sites, comparison with modern relatives, biomechanical modeling & dinosaur trackways that show pairing or courtship behavior. Dinosaurs' anatomy shows they almost certainly mated through internal fertilization via the cloaca, with the male mounting the female from behind. Their physique, tail mobility & balance made this entirely feasible, even for giants weighing 20-70 tons (18-63 metric tons).

[scienceguy22]

Aunt Etty and the naughty mushrooms.

"Aunt Etty" is a shortened version of Henrietta and was her nickname within the extended Darwin family. Etty had an unusual hobby, namely the collection of phallic mushrooms known as stinkhorn mushrooms. She loved nature & liked the fact that the "shrooms'" explicit shape embarrassed polite Victorian society. She had a natural curiosity about nature & the world growing up in her father's (Charles Darwin) household. This meant constant exposure to unusual organisms, & the stinkhorns fit the bill. Etta reportedly burned the shrooms to "protect the morals of the maids." Little known is the fact that Darwin's daughter Henrietta was a collaborator with her dad, Charles Darwin, editing several of Charles Darwin's works. Etta was the third of Darwin's 10 children, whom he had with his first cousin, Emma Wedgwood.

Stinkhorn mushrooms are indeed stinky. The shrooms' scientific name is Phallus impudicus, which contains over 50-100 different complex molecules—but a few of their molecules are the real "stink stars." Dimethyl trisulfide—a sulfur compound that smells like rotten cabbage, decomposing meat & sewage. Other dimethyl oligosulfides (like dimethyl disulfide) add garlic rot, onion rot & putrid notes. Other volatile chemicals are putrescine & cadaverine—self-explanatory terms. It also has indole (fecal smell) & skatole (stronger fecal smell). The stinkhorn is basically a tiny chemical factory pumping out "dead-thing smell" molecules. There's one reason the shrooms do this, and that is to attract flies. They land on the fleshy, soft, gelatinous, sticky, oozy head of the mushroom called the gleba, which is loaded with spores; walk around; feed & get covered in spores. Then they fly away, carrying spores on their legs, mouthparts, & bodies to new locations.

Stinkhorn fungi come from eggs, but in fungi, the word "egg" is just a nickname for a round, enclosed, rubbery growth chamber. The stinkhorn egg is a gel-filled ball, packed with a folded-up mushroom, waiting for the right moment to inflate & burst upward. Pressure builds as the shroom absorbs water, swelling like a balloon. The stem bursts upward in hours—sometimes 2-4 in (5-10 cm) in a morning. Finally, its cap (gleba) emerges on the tip of the mushroom. Inside the egg is the entire mature mushroom, already formed but compressed like a folded umbrella. Most mushrooms spread via underground mycelial "shoots" or by emitting spores in the air, but stinkhorns mainly spread by flies. Because the stinkhorn was thought to be an evil omen, folklore gave them names like "Devil's eggs," "Witches' eggs," & "Death baby," assuming that if one grew close to a family member's house, death would be imminent.

In France, in 1926, members of the sect Notre-Dame des Pleurs attacked a clergyman (who they believed was possessed) for casting spells on birds to fly over the sect leader's garden, "where their droppings gave rise to fungi of obscene shapes, emitting such appalling odors that those who breathed them were smitten with horrible diseases." A 20th-century mycologist called stinkhorns "Nature's most indecent joke."