BrainGrub is an English Telegram Channel that provides general knowledge trivia. It is updated once...
WHAT IS QUICKSAND? Reading time: 38 secs If you grew up on a steady diet of Hollywood adventure movies, you'd be forgiven for thinking that stepping into quicksand would spell the end of you. Despite the persistent Hollywood trope, a quick google search confirms death by quicksand is rare. Quicksand is sand that is waterlogged and can be seen as a very soupy mixture of sand and water. Water saturation in quicksand reduces the friction between sand particles. This disrupts the sand's ability to support much weight. But because we are less dense than the average quicksand density, it is rare for us to be completely sucked under the way you see in movies. Quicksands usually occur in areas such as natural springs, riverbanks or on beaches at low tide. Most people die from quicksand through drowning (when the tide comes in in coastal areas), hypothermia (difficulty maintaining body temperature in wet quicksand), suffocation (if you are deep enough and the sand presses against your chest), and dehydration.
WHAT ARE DEEPFAKES? Reading time: 38 secs Seeing is believing, as the saying goes, but deepfakes are something that would turn this phrase on its head. The term deepfake is an amalgamation of the words "deep learning" (a term used in AI) and "fakes". It started when a Reddit user, named "deepfakes" started posting porn videos that were altered to include famous actresses' faces. It uses machine learning to study the patterns in a person's facial expressions from different videos and photos and maps these onto another person's face. While doctoring photos have been around for centuries, the process was a tedious one.This was especially true for videos. Machine learning techniques can automate this process and make it easier to create a realistic fake video.As of now, people can still spot deepfakes upon closer inspection but like all technologies, deepfakes are only going to get better with time. Deepfakes are worrying in a world where fake news are proliferating and trust in news outlets are deteriorating.
WHY ARE DINOSAURS SO BIG? BrainGrub Shorts, Reading time: 40 secs The largest land mammal is an extinct rhino, Paraceratherium which was 26-foot long and weighed 15 tonnes. Despite this, it's nothing compared to the dinosaurs. Some theories as to why some dinosaurs were able to grow so big include having hollow bones and air sacs as well as being able to lay eggs. Hollow bones allow dinosaurs to be lighter than mammals of similar size. Despite being 4x larger than Paraceratherium, the Supersaurus is only 2.5x heavier. This prevents them from collapsing under their own weight. Having air sacs as breathing systems gave the dinosaurs the ability to breathe more efficiently. Air sacs also help by filling the spaces in between bones, making them strong but light. Lastly, dinosaurs lay eggs, preventing the problem of having to carry a huge baby and all the costs associated with it. While the above may have allowed the dinosaurs to be big, not all did. The smallest dinosaur was about the size of a chicken.
HOW BUG SPRAYS WORK BrainGrub Shorts, Reading time: 37 secs It isn't easy being a roach. As one of the most reviled creatures on this planet, roaches will get killed upon sight through any means possible. A slipper, a rolled up newspaper or a bug spray. While the other 2 methods are death by brute force, death by bug spray isn't as obvious. When we spray insecticides on a roach, an organic compound called pyrethroid enters through small pores on its body. Pyrethroids are synthetic chemicals that mimic the natural form of insecticides produced by chrysanthemum flowers. Instructions sent from the insect's brain to the rest of the body to maintain bodily functions weaken as it travels to its destination. Sodium channels help by maintaining the strength of these impulses as it moves through the nerve cells until it reaches its target. Pyrethroids disrupt this mechanism, thus preventing impulses sent from its brain from reaching anywhere. This results in major systems shutting down, killing the roach.
WHAT IS THE AURORA BOREALIS? BrainGrub Shorts, Reading time: 38 secs The Vikings believed that the lights were reflections of the Valkyries' armor as they marched towards Odin. Some Inuits thought that the lights in the sky were the spirits of their ancestors dancing and the Greeks associated these lights with bad omens. Whatever the meaning the ancient people attributed to the lights, the Aurora Borealis is a sight to behold. With the advancement of the sciences, we know that the Aurora Borealis or the Northern Lights are caused by the Earth's atmosphere interacting with charged particles from the Sun during a solar flare. As the particles from a solar flare reach Earth, they are channeled along Earth's magnetic fields towards the North and South poles. These particles then interact with the atoms and molecules in our atmosphere, exciting and causing them to release photons. These photons are the lights that we see in the sky during an aurora. Their southern counterparts are known as aurora australis.
What is the Antikythera Mechanism? BrainGrub Shorts, Reading time: 37 secs Laptops, desktops, and increasingly, mobile devices are the computers that we use in our everyday life. It so ubiquitous that we rarely pause to wonder how did it all start. Built two thousand years before the personal computer revolution, the Antikythera Mechanism is believed to be the first computer ever made. Found in 1902 off the coast of the island of Antikythera, the mechanism was used to predict astronomical points such as the location of the planets and stars on a calendar month as well as to predict the next Olympic games. The functions of this mechanism were better understood upon the discovery of ancient Greek text inscribed on parts of the machine that were not seen until modern imaging methods were used. On the 115th anniversary of the discovery of the Antikythera mechanism, Google dedicated a Doodle to celebrate a device that illuminates "how a rusty remnant can open up a skyful of knowledge and inspiration".
WHY ARE RAIN CLOUDS GREY? BrainGrub Shorts, Reading time: 40 secs Bliss is the name of the default wallpaper for Microsoft's Windows XP operating system. It features a picturesque green hill with clear skies. Such images of a clear blue sky with white clouds usually evoke a sense of calm. Yet the very same mechanism that makes clouds white can also turn clouds grey and menacing on a rainy day. The sky appears blue because the tiny molecules in the air scatter sunlight as it goes through the atmosphere. As blue light is scattered more, this causes the sky to appear blue. In clouds, water droplets are the ones scattering sunlight. Water droplets are larger and will scatter all colors more or less equally. This means that the sunlight that gets scattered by clouds remains white and hence the white color of clouds. Rain clouds are usually wider and taller, making it more likely that the light gets scattered to the top or the sides of the cloud.Thus, less light reaches the bottom and this makes it look grey.
WHAT IS reCAPTCHA? BrainGrub Shorts, Reading time: 41 secs We all have encountered it on the internet. Just a click away from completing what we set out to do and we are stopped by a pop up asking us to identify some pictures or enter some text we see before we can proceed. This is reCAPTCHA, a system used to determine if the user is a real human. It is an ingenious way of stopping bots by killing two birds with one stone. It solves the need for users to prove that they are real humans and Google's problem in digitizing its Google Books archive. Thanks to our collective efforts, in 2011, Google has completed digitizing its entire archive. Today, we no longer need to transcribe words. Instead, we are asked to identify pictures of a certain kind. Using the same method as before, we are being used to train AI algorithms to identify objects in pictures. This helps in improving Google services like Google Maps and Google Photos search results as well as aiding driverless cars in navigating roads in the future.
WHAT IS A MASS EXTINCTION EVENT? BrainGrub Shorts, Reading time: 36 secs Since life began on Earth 3.5 billion years ago, it has experienced 5 mass extinctions due to rapid changes in the environment. Such changes prevent life forms on Earth from adapting to their new surroundings through the slow process of evolution and die off en-masse. Mass extinctions are defined as a huge loss of biodiversity over a short time. The big 5 extinction events started with the Ordovician-Silurian Extinction (70% of species lost), 450 million years ago up to the End-Cretaceous Extinction (75% of species lost) that killed off the dinosaurs, 66 million years ago. Some of the accepted explanations for mass extinctions include sea level falls, global warming and cooling, wide scale-volcanic eruptions, anoxic events and asteroid collisions. Today, scientists suspect that we are in the 6th mass extinction event because of human activities on Earth and estimate that by the year 2100, half of the world’s species will go extinct.
WHAT IS "THE FAR SIDE OF THE MOON"? BrainGrub Shorts, Reading time: 37 secs China's space ambitions were made clear early this year with its spacecraft, Chang'e 4, becoming the first vehicle to land on the far side of the moon, in the Von Karman crater. The moon is tidally locked with Earth and humans couldn't see the far side of the moon until the invention of space probes. Yet, while we have taken pictures, no rover has ever touched down here before Chang'e 4. The rover will conduct experiments on the moon's surface to learn its origins and to understand the effects of solar winds striking the moon's surface. Brought on board is also a mini ecosystem of life on Earth, to study the behavior of lifeforms in a low-gravity environment. Like the moons of other planets, ours is tidally locked because Earth's gravity has slowed the moon's rotation down enough such that its orbital and rotational period matches. This causes the same side of the moon to always face planet Earth.
HOW TALL CAN WE BUILD? BrainGrub Shorts, Reading time: 37 secs The Great Pyramids of Giza was the world's tallest structure for 3,800 years before the Lincoln Cathedral came about in 1300. The record was then broken by the Washington Monument (1884) and soon after, the Eiffel tower. This trend of breaking records accelerated with the invention of skyscrapers. The tallest structure today is the Burj Khalifa in Dubai, though not for long. Construction of the next tallest structure, The Jeddah Tower is already underway. Its completion is set for 2020. With records broken every so often, we’ve got wonder: how much taller can we continue to build? In theory, how high we can build is only restricted by our own imagination, as well as economics, and politics. Throw in enough money and engineers will figure out how to build even taller structures. There are even ideas to build a planet-to-space transit system, called space elevators. If this comes to fruition, it will surely be the tallest structures ever built.
WHAT ARE BEHAVIOUR-ALTERING PARASITES? BrainGrub Mini-Series, Reading time: 40 secs Cockroach Walkers The female parasitic jewel wasp frequently takes on victims six times its size. Not an easy task and yet she has to do this repeatedly as she carries many eggs but only injects one egg per victim, the common cockroach. She attacks by injecting her venom twice into the cockroach. The first into the thorax to paralyze it and the second, into its brains which turn it into a zombie. She then flies off in search for a burrow before coming back to chew off the victim's antennae. She drinks the blood coming out of it to recover the energy she spent earlier. Satisfied, she bites down on what remains of the antenna to lead the cockroach back her burrow where she lays an egg on its leg before sealing the burrow. Once the egg hatches, the larva slowly eats the cockroach from the inside out until it dies. The larva then pupates inside the hollowed out body for a month before finally emerging as an adult wasp.
WHAT ARE BEHAVIOUR-ALTERING PARASITES? BrainGrub Mini-Series, Reading time: 38 secs Zombie Bodyguards In the 1979 movie Alien, a Xenomorph incubates inside a human host before bursting out of its host's body. Multiply that by 80 and you get the parasitic wasps that use caterpillars of the geometer moth as its hosts. These wasps are called Glyptapaneteles. The females of this species inject their eggs, up to 80 at a time, into living caterpillars. In there, the larvae mature by feeding on the caterpillar's insides and avoiding vital organs to keep the caterpillar alive. Once the larvae mature, they secrete chemicals that paralyzes the caterpillar and chew their way out. Despite enduring all that, the caterpillar survives and does something strange. It then starts guarding the larvae as they wrap themselves in cocoons.The caterpillar stands guard until it starves to death. Scientists have found one or two larvae remaining inside a dead host and suspect that they remain behind to continue to control the host.
WHAT ARE BEHAVIOUR-ALTERING PARASITES? BrainGrub Mini-Series, Reading time: 36 secs Zombie Ants The Zombie Ant Fungus, O. unilateralis, attacks carpenter ants though it's spores. When an ant comes across these spores, it enters the ant's body as single cells that float around the ant's bloodstream. The cells then start replicating itself before building tubes to one another. By doing so, they can communicate and exchange nutrients. Despite infiltrating the entire ant's body, it leaves the victim's brain intact. Scientists suspect that the fungus directly controls the ant's muscles instead of its brain, just like how a puppeteer commandeers a puppet by manipulating different strings. When the time is right, the fungus forces the ant to move up a plant near its colony and clamp down on the underside of a leaf or twig, to die a slow death. The fungus continues to devour its host while growing a spore-releasing stock out of the victim's head. These spores drift onto the ground below creating more zombie ants.
WHAT ARE BEHAVIOUR-ALTERING PARASITES? BrainGrub Mini-Series, Reading time: 36 secs Crazy-eyed snail Leucochloridium is a worm that invades a snail's eyes and pulsates to attract attention. It starts by the worm reproducing in a bird's gut, after which its eggs are released in the bird's droppings. A grazing snail nearby sees the delicacy and eats it. These indigestible eggs travel into the snail's digestive system to begin its next stage as a sporocyst. This worm has no mouth and just lazes around absorbing its host's nutrients through its skin. As it grows, it invades the snail's eyes and forms brood sacs that pulsate, mimicking caterpillars. To change the snail's nocturnal behavior, it releases chemicals that makes its host go out in daylight and seek higher grounds so that birds may spot it. Eventually, the snail will get its "caterpillar eyes" plucked out by birds. Despite this, the snail will survive and regenerate its lost eyes, becoming yet another potential host for the parasite's offspring.
WHAT ARE BEHAVIOUR-ALTERING PARASITES? BrainGrub Mini-Series, Reading time: 36 secs Kamikaze Crickets Parasites invade your body and turn you into a zombie to do their bidding. It sounds like a science fiction story but it's a reality for many crickets in the wild. Horsehair worms are parasites with a complex life cycle. It starts off life as a tiny water-borne larva that will infect other aquatic invertebrates such as mosquito larvae. Once it's successful, it will start the following stage as a cyst. The next stage begins if it gets eaten by its final host, the cricket, where it matures into a foot long worm, curled up in the cricket's body. When the horsehair worm is ready to reproduce, it will start to release chemicals to control the insect's brain into seeking bodies of water and doing a kamikaze dive into it. The worm will then emerge and swim away to find a mate, starting the worm's life cycle all over again while its host dies a watery death. GIF: Source
WHAT ARE BEHAVIOUR-ALTERING PARASITES? BrainGrub Shorts, Reading time: 36 secs In this world, crickets willingly jump into the water and drown, nocturnal snails climb out openly during the day to be eaten by a bird and cockroaches voluntarily become food for a wasp’s growing larvae. These are examples of hosts that have fallen prey to parasites that need them for its transmission. They alter the host’s behavior, making them careless so that the parasites can continue their lifecycle after being eaten. Luckily for us, there aren't many known parasites that alter our behavior. One of those is a parasite is called Toxoplasma gondii. It’s excreted by cats in their feces, which are eaten by rats. Infected rats then behave riskily in front of cats, only to be eaten and allow the parasites to continue its life cycle. In humans, infections occur when we clean litter boxes, eat unwashed vegetables or consume undercooked meat. Infections can cause aggressiveness, impulsivity and increased risk of suicidal behavior.
WHAT IS BIOMIMICRY? BrainGrub Shorts, Reading time: 37 secs The initial design of bullet trains in Japan had a problem. Traveling at high speeds into tunnels, these trains would create pressure waves that reach the tunnel exit at the speed of sound. This caused noise pollution, called tunnel boom. To solve this problem, the Japanese looked to nature, the Kingfisher, which can dive into water with minimal splashing. The trains' noses were then redesigned to look like a Kingfisher's beak which reduced noise pollution and also made the trains more efficient. The above is but one of the many examples of biomimicry. It is the adaption of nature’s designs to solve human problems. Nature has had years of evolution, naturally selecting different forms to find the most efficient and effective solutions to problems it encounters. As we face more challenges such as environmental pollution, the above example illustrates how we can be inspired by nature to make our designs more efficient, cleaner, and yes, quieter.
WHAT IS THE BIRD BOX CHALLENGE? BrainGrub Shorts, Reading time: 39 secs The internet can be a weird place. From the ALS Ice Bucket Challenge to the tide pod challenge, people, especially teenagers are easily suckered into doing them, even when these challenges can cause harm. The latest challenge that is trending now is the Bird Box challenge. It’s a fad that has people wearing a blindfold as they go about their day for a period of time. It takes the core concept of Bird Box (a movie) where a mother tries to save her children from supernatural forces that cause you to die by suicide should you lay eyes on them. She and the other characters in the movie spend most of the film blindfolded while trying to reach safety. Unlike the other challenges out there, this one seems relatively harmless though some people have taken it too far such as driving on the roads with their eyes covered. Netflix has tweeted to warn people against the Bird Box Challenge and to “not end up in the hospital due to memes”.
WHY ARE AIRPLANE WINDOWS OVAL? BrainGrub Shorts, Reading time: 37 secs Look at the image above. Do you notice anything different? If the title is not a dead giveaway, you would have noticed that the airplane’s windows are square, not oval like we typically see on commercial airplanes today. Square windows were actually commonplace until the late 1950s. It was after 2 plane crashes,BOAC Flight 781 and SA201 that prompted the aviation manufacturer, de Havilland to change its design to the oval-shaped windows we see today. Inquiries into the crashes revealed that the square windows were the cause of structural weaknesses in the fuselage which led to it breaking apart in the air. Square windows cause the surrounding material to experience a higher pressure felt elsewhere in the cabin. Sharp corners are spots where stress concentrates and having four corners could mean disaster when subjected to pressure. Curved windowpanes allow the stress to be distributed around it better as it does not have any focal point.