Tag: nature

Posted in Science & Nature

Periodical Cicada

Posted on by Jinavie

In certain parts of eastern North America, it has been noted for centuries that some summers seem to bring a massive swarm of cicadas. Observant naturalists such as Pehr Kalm noted in the mid-1700’s that this mass emergence of adult cicadas happened every 17 years. Since then, a similar pattern has been observed with many different broods of cicadas, with precisely 17 or 13 years between emergences of mature cicadas.

What could possibly explain such a specific, long gap between these spikes?

This phenomenon has been well-researched and the species of cicadas (Magicicada) are known as periodical cicadas. They can be distinguished by their striking black bodies and red eyes. Like most cicadas, periodical cicadas start their lives as nymphs living underground, feeding on tree roots. They take 13 or 17 years (depending on the genus) until they emerge all at once in the summer as mature adults – far longer than the 1-9 years seen in other cicadas. After such a long period of growth, they emerge for a few glorious weeks in the sun to mate, before laying eggs and disappearing.

The astute reader would notice that both 13 and 17 are prime numbers (a number divisible only by itself or 1). Is this a sheer coincidence or a beautiful example of mathematics in nature?

This curious, specifically long period of maturation has been a great point of interest for scientists. The phenomenon of mass, synchronised maturation is a well-documented survival strategy known as predator satiation. Essentially, if the entire population emerges at the same time, predators feast on the large numbers, get full and stop hunting as much. The surviving proportion (still a great number), carry on to reproduce and the species survives.

One theory holds that the prime numbers are so that predators cannot synchronise their population booms with the cicadas. If the cicadas all emerged every 4 years, a predator who matures every 4 or 2 years could exploit this by having a reliable source of food in a cyclical pattern. 13 and 17 are large enough prime numbers that it would be very difficult for a predator to synchronise its maturation cycles with.

Another possible theory is that it is a remnant of a survival strategy from the Ice Age. Mathematical models have shown that staying as a nymph for a longer period increased the chances of adults emerging during a warm summer, rather than when it is too cold for reproduction. This resulted in broods of varying, lengthy cycles, but this created another problem: hybridisation. When broods of different cycle lengths intermingled, hybridisation could occur and disrupt the precise timing of maturation cycles, decreasing the brood’s survival rate. Prime number cycles such as 13 or 17 years have a much less chance of hybridisation, increasing the survival rate.

As Galileo Galilei said, mathematics is the language in which the universe is written. It is fascinating to see examples of how maths can influence natural phenomena, even the life cycles of insects.

Posted in Science & Nature

Brocken Spectre

Posted on by Jinavie

There is a Scottish legend that speaks of a terrifying giant that lives atop Ben Macdui, the second highest peak in Britain. Am Fear Liath Mòr (Gaelic for “Big Grey Man”), is describes as a gigantic, dark figure with a fuzzy appearance. It is said to inspire a feeling of fear, eeriness and apprehension. It has been sighted by multiple lone climbers exploring the peaks of Ben Macdui.

Am Fear Liath Mòr has been classically described as a supernatural being, rather than a cryptid such as Bigfoot or the Yeti. However, there is an even more interesting and scientifically plausible explanation. Am Fear Liath Mòr is the climber themselves.

As poetic as this sounds – that you are confronted by a gigantic shadow of your inner self at the top of a misty mountain – it is a well-documented phenomenon known as a Brocken spectre.

This happens when the sun is at an angle, shining from behind the observer into mist or fog at the top of a peak. A shadow is cast and appears magnified because of the vast distance between the observer and the fog. Because the background is a fog with little feature, the observer loses their depth perception and see an ill-defined, massive being. The rippling of the water droplets, wind and the observer’s own movements all contribute to the shape appearing alive.

Furthermore, there are many factors that would cause the eeriness commonly reported by people who witness a Brocken spectre. Winds echoing through a pass tend to create very low-frequency sounds that cause uneasiness in people. There is likely a large psychological component as well, as the climbers tend to be alone in a dark mountain, while fatigued from their long climb.

Brocken spectres are a classical example of just how awe-inspiring natural phenomenon can be, especially after understanding the scientific principle behind them.

Posted in History & Literature

Beast Of Gevaudan

Posted on by Jinavie

In 1764, a young woman herding cattle in Gevaudan, France, told the story of how she was attacked by a giant, fearsome beast. She reported that the beast charged towards her, but was only stopped by the bulls that defended her. The beast was described as being as big as a calf, with a large dog-like head with exposed very large fangs and dark reddish fur with black streaks. Not long after this story, a young boy living nearby was violently killed, with his throat torn out. The number of people attacked and killed by this mysterious beast grew and grew. The population of Gevaudan was terrified. No wolf or dog had been known to be as large as the beast reported by survivors, nor as vicious as this.

The story of the so-called “Beast of Gevaudan” was heard by Louis XV, who responded by dispatching professional wolf-hunters to Gevaudan to slay the beast. One of these men was called Francois Antoine – a veteran wolfhunter. Over the coming months, he hunted several large wolves, but the attacks continued.

On September 21, 1765, Antoine finally encountered the beast. It was a ferocious wolf-like animal, about 1.8m long and 70cm tall. Antoine shot it several times, in the eye, shoulder and side. The beast withstood the first couple of shots and finally fell to the ground after the third. But as Antoine and his colleagues cheered, the beast stood back up and charged Antoine. It took two more shots to finally slay the beast. Survivors of attacks were able to identify the beast as the true Beast of Gevaudan. The beast was embalmed and stuffed for display and the populace of Gevaudan celebrated the end of the terror, with Antoine being celebrated as a hero and expert wolfslayer.

However, the story did not end there. Attacks continued for years even after the Wolf of Chazes was slain. The ultimate end to the story is credited to a hunter named Jean Chastel, who shot and killed a large wolf-like beast in 1767, after which the attacks stopped. Some say that he used a blessed silver bullet – possibly originating the myth that werewolves can only be killed by silver bullets.

It is still unclear what exactly the Beast of Gevaudan was. Some believe it to be a large wolf, but most historians agree that it was likely a wolf-dog hybrid given its large size, unusual ferocity and distinct coloured fur. Other theories include the beast being a large red mastiff, an Asian hyena or a pack of wolves, which is likely given the sheer number of attacks in such a short space of time. All in all, the final kill count of the Beast of Gevaudan is estimated between 80 to 120 people, with a further 49 injuries.

Posted in Science & Nature

Atrophy

Posted on by Jinavie

With exercise, muscles get bigger and bigger to generate enough power to meet the demand. This is called hypertrophy, where the cells in tissue divide faster to increase their numbers and build mass. When you do not use the muscles as much, the body decides to recycle the precious resources by breaking down the extra muscle. This is called atrophy – also known as wasting.

Muscles are not the only things that atrophy. The less you think deeply and explore your curiosities, the more your intelligence and wisdom atrophies. As you care less, your heart and ability to love atrophies. As you smile and laugh less, your happiness atrophies.

Like much of nature, the human body dislikes the status quo and strives to avoid stagnation. It continuously breaks down old, unnecessary things to make way for new, different things that will help you better adapt to your environment.

Unfortunately for us, that means to maintain the parts of us that we like, we must train and use the relevant “muscles” – whether it be lifting weights, reading books or laughing heartily for no reason.

Posted in Science & Nature

Mandrake

Posted on by Jinavie

The plant Mandragora officinarum, more commonly known as mandrake, is a plant that has interested people in various fields throughout history. Firstly, the root is split into two at the end, giving the uprooted plant the appearance of a human being. Secondly, it belongs to the nightshade family, containing plants such as the infamous deadly nightshade (belladonna), tobacco, Datura, petunia, tomatoes and potatoes. Like its relatives the belladonna and Datura, mandrakes contain alkaloids such as atropine, scopolamine and hyoscyamine. These substances are potent (and toxic) hallucinogenics and sedatives, which is why they have had various uses ranging from witchcraft to anaesthesia to murder through poisonings.

The shape of the mandrake and its hallucinogenic effects have given it notoriety. Legend goes that when a mandrake root is dug up, it shrieks with such terror that anyone who hears it will die – possibly referring to the toxicity of the alkaloids. Historical texts give detailed instructions on digging up mandrakes by tying a hungry dog to the root and making it pull the plant out of the ground when the owner is out of earshot and he lures the dog with food.

Other folklore suggest that mandrake only grow when the ground is inseminated by semen dripping from a hanged man. This folklore is likely fuelled by the mandrake’s human-like appearance. Ancient and medieval literature associates mandrake being used to make fertility agents and love potions(again, likely related to the hallucinatory, sedative effects). Mandrake is a common ingredient in magic rituals of various kinds, such as in Wiccan rituals.

Alkaloids extracted from mandrake have been used in medicine since the Middle Ages, where extracts were used to anaesthetise patients before surgery, as it has a sedating, hypnotic effect. Eye drops made from mandrake extract were used for hallucinations and mandrake syrups were used to aide sleep. In modern medicine, scopolamine is used in motion sickness patches and atropine is used to speed up the heart rate when it slows too much.

The extensive list of supposed and actual properties of mandrake has made it a popular plant in fiction as well and it can be found in countless works throughout time, such as works of Shakespeare, Sir Arthur Conan Doyle and J.K. Rowling.

Posted in Psychology & Medicine

Stampede

Posted on by Jinavie

In the movie The Lion King, Simba’s father Mufasa is killed when he is trampled by a wildebeest stampede. Stampedes are a common behaviour in herd animals such as cattle, horses, wildebeests and elephants. When one animal is startled by something, it shows a fear response which then startles the animals around it. This startle propagates rapidly through the herd and the entire herd begins running away from whatever caused the first startle. They run with no clear reason or direction – it is a mindless rush of fear. Because of this, anything in the path of a stampede is crushed to death as the herd blindly rushes forward with impressive power and energy.

The destructive nature of a stampede not only affects whatever is in the path of the herd, but the herd itself. Native Americans are well-known for their buffalo jump style of hunting, where they would herd wild bison then trigger a stampede. They would direct the stampede towards a cliff and the frightened bison would blindly jump off the cliff to their deaths.

As deadly as a bison or wildebeest stampede may be, there is a species that causes far greater damage to humans when they stampede: us. Human stampedes are a well-known phenomenon documented throughout history, from crowds rushing away from a city being bombed to religious pilgrimages to sports games. Just like animals, when there is a large enough crowd of people, a simple spark of fear can cause mass panic.

This is described as the “falsely shouting fire in a crowded theatre” effect. In 1941, 4000 people were killed when the Japanese army bombed the Chinese city of Chongqing, causing a mass panic at an air raid shelter. More famously, 96 people were killed in the Hillsborough stadium crush in England, 1989, when crowds of people attending a soccer match squeezed into a tunnel blocked at the other end. There have been several incidents during the pilgrimage to Mecca where hundreds of people were killed during stampedes.

In human stampedes, death is not usually caused by trampling but by compressive asphyxiation. The sheer force of people pressing on each other limits chest expansion, making breathing impossible. The force of a panicked crowd can be great enough to bend steel bars. This phenomenon is also called crowd crush.

Posted in Science & Nature

Intelligent Life

Posted on by Jinavie

One of the great questions in science is “could intelligent life develop on planets other than Earth?”. Even the general populace has heard of programmes such as SETI (Search for Extraterrestrial Intelligent Life) and mathematical models such as the Drake equation that attempt to predict the possibility of extraterrestrial intelligent civilisations. But an equally intriguing question we seem to neglect is: “could intelligent life develop on Earth?”.

The definition of “intelligent life” is hugely varying, but nonetheless attempts have been made to compare our intelligence level to other animals. From the pool of research throughout the decades, the most “intelligent” non-human animals appear to be chimpanzees, bonobos, great apes, dolphins, elephants, certain parrots, ravens and rats. There is much research on the intelligence of cephalopods (e.g. the octopus) that has shown promise. If we were to shift the focus from individual intelligence, we could also consider “civilised” animals such as ants, as they are capable of building vast cities with intricate societies. All of this shows that intelligence is not exclusive to our species. We have simply walked down the path of evolution where the trait of ever-increasing intelligence, knowledge and wisdom have allowed us to adapt to and survive our environment. Ergo, it is fair to consider the possibility that other animals are walking a similar path that may lead to the making of a species with intelligence comparable to us.

However, this only raises the theoretical possibility of intelligent life. What is the realistic, practical possibility of intelligent life developing on Earth in the near future? Put another way, could intelligent life develop in the presence of a higher intelligent life (e.g. humans)? The road that brought us to throne of “the most intelligent species on Earth” was not an easy one. We are but one of many other hominid (human-like) species that evolution produced while tinkering with the concept. For example, there was a time when we (Homo sapiens) shared the Earth with other intelligent hominids such as the Neanderthals. The Neanderthals are commonly pictured as simple, knuckle-dragging apes but in reality they were just as intelligent as Homo sapiens during that time. They had a culture similar to our own, developed stone tools just as complex and even made cave paintings in a display of art. The reason why we are not breaking bad with Neanderthal neighbours now is that (according to one theory) we successfully outcompeted them, driving them to extinction (there is debate whether genocide and cannibalism was involved).

Evolutionarily speaking, it makes sense for an intelligent species to wipe out another species trying to compete with the ecological niche of intelligence. This has been discussed in many works of science fiction, such as Planet of the Apes where the emergence of intelligent apes leads to the destruction of human civilisation. Arthur C. Clarke discussed this as a side plot in his novel The Songs of Distant Earth. Upon discovering a species of sea scorpions that show signs of intelligence such as social hierarchy and metal collecting, the scientists suggest that they should allow it to develop, but ultimately the government decides to eradicate them as soon as they attempt to migrate to land.

Suffice to say, given our track record in history involving the countless times colonists wiped out other civilisations to serve their purpose, there is a good chance that any new intelligent life would immediately be removed by us if they had the misfortune of arising during our time.

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Posted in Psychology & Medicine

Belladonna

Posted on by Jinavie

The belladonna flower has a name that means “beautiful lady” in Italian. However, its other common name has a completely different meaning – the deadly nightshade. Both names can be explained by the uses of the flower throughout history. The deadly nightshade (Atropa belladonna) is a small shrub with purple bell-shaped flowers and shiny black berries. All parts of the plant contain various toxins such as atropine, scopolamine and hyoscyamine. These alkaloid toxins are included in a group of chemicals called anticholinergics, because they act on cholinergic receptors on neurons, which are involved in activating the parasympathetic nervous system. As cholinergic receptors are widely utilised throughout the body, anticholinergic toxicity causes a wide range of symptoms.

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The main symptoms of anticholinergic toxicity are best remembered using the following mnemonic:

  • Hot as a hare (increased temperature – reduced temperature regulation)
  • Blind as a bat (blurred vision – dilated pupils)
  • Dry as a bone (dry skin, eyes and mouth – decreased secretions)
  • Red as a beet (flushing – dilation of blood vessels)
  • Mad as a hatter (hallucinations and agitation – neurological interaction)

The name deadly nightshade is obvious as severe toxicity leads to seizures, coma and death. The reason why the deadly nightshade is also called belladonna is that the diluted extract from the plant was used as an eye drop to dilate women’s pupils – a look considered beautiful then (nowadays the effect is used to examine the eye). The toxins extracted are used in other fields of medicine too. Although not used now, anticholinergics were used as an anaesthetic for surgery due to its neuropsychiatric effects. However, atropine is still used in the emergency setting to reverse bradycardia (excessively slow heart rate), as anticholinergics speed up the heart rate. This highlights the fundamental principle of medicine that “the dose makes the poison”. For the only difference between medicine and poison is the dose… and intent (Oscar G. Hernandez, MD).

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Posted in Science & Nature

Shared Bodily Warmth

Posted on by Jinavie

Body heat is a vital condition that animals need to survive. It is so vital that when you are hypothermic, your body will override almost everything else to conserve heat as much as possible. Without enough heat, the chemical reactions that fuel your cells will grind to a halt and you will die. To solve the issue of getting heat, nature came up with two answers: endotherms and ectotherms.
Endotherms are organisms that produce their own heat (e.g. mammals) by trapping the heat produced by metabolism and through extra mechanisms such as shivering. Ectotherms rely on absorbing environmental heat (e.g. reptiles), usually through the sun. Because of this, ectotherms suffer a much greater range in body temperature. This means that animals such as lizards will be slower and more sluggish when it is cold.

Being in a cold environment quickens the process of heat loss, robbing you of the precious heat you generate. A solution to this is shared bodily warmth. Also known as kleptothermy, this is a common thermoregulation strategy where a group of animals huddle together to share the heat generated by each other. This increases the efficiency of heat generation (thermogenesis) and the group as a whole can stay warmer for longer. This behaviour is commonly seen in communal animals such as mice, who huddle together even when they are newborns (newborns lose heat much quicker than adults due to the difference in weight to surface area ratio). Some ectotherms such as snakes and lizards also engage in kleptothermy, where by huddling together they increase their effective mass and reduce heat loss.

An interesting case of kleptothermy is seen in Canadian red-sided garter snakes, where the heat is not shared, but stolen. A male snake will sometimes emerge from hibernation and begin to produce fake pheromones to attract other males as if it were a female. Other males are fooled into thinking that the snake is female and approach it to mate. Through this strange process, the snake is able to steal the heat from its rival males and use the extra energy to mate with an actual female (or lose it to an even more cunning male snake).

Posted in Science & Nature

Thuder And Lightning

Posted on by Jinavie

The best or worst part (depending on your preference) about a dark and stormy night are the majestic flashes of lightning and booming thunder. Most people confuse the two terms, typically using “thunder” to describe both, but technically thunder is the sound produced by lightning, which is the flash of light. Lightning occurs when dense clouds become electrically charged due to the collision of water molecules. As charge builds up, the cloud becomes negatively charged. The negative charge becomes so intense that it begins to push electrons towards the surface of the Earth, creating a positive charge. Electricity always flows from a negative charge to a positive charge through a medium. The intensity of charges causes the air to become ionized (plasma), making it suddenly conductive and allowing the electricity to flow from the cloud to the ground. This is seen as a flash of intense light. As the electricity travels through this channel of air, it superheats the air and causes a massive expansion of air, much like an explosion. This creates an intense shockwave burst, producing a sound that we call thunder.

Lightning is a deadly force of nature. It clocks a peak voltage of somewhere between 30 million to billions of volts – far exceeding the electricity that can be generated by humans. When a lightning bolt strikes a human, it has a mortality rate of between 10~30%. The two effects of lightning on the human body is electrical shock and heat. As lightning flashes over the skin to reach the ground, it leaves a striking pattern known as Lichtenberg figures (see below), showing the path of the electrical breakdown. The intense electrical burst can cause loss of consciousness, arrhythmia or sudden cardiac arrest. The heat generated by the electricity can cause severe burns both externally and internally. It can literally fry internal organs causing permanent damage to the heart, lungs and brain. Neurological symptoms such as amnesia, confusion, sleep disturbance and chronic pain have also been reported. Strangely, there are also reported cases of lightning curing ailments such as blindness, deafness and baldness.

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Because lightning is light and thunder is sound, one can calculate how far away lightning struck using the time between the lightning flash and the sound of thunder. Sound travels at 340m/s, so by multiplying the number of seconds between the lightning and thunder by 340, you can deduce the distance in metres. For example, if you see a lightning strike and then hear thunder after 7 seconds, the lightning must have struck 340m x 7s = 2380m = 2.38km away.

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