Tag: evolution

Posted in Science & Nature

Endling

Posted on by Jinavie

Extinction is when there are no more members of a given species left. Countless species have come and gone throughout history, such as the dinosaurs. We are currently going through the most recent episode of mass extinction where a vast number of species are being wiped out from the face of the Earth. The cause of this mass extinction is us.

So-called the Anthropocene Extinction, modern humans have been responsible for the extinction of millions of species over the course of our history. This ranges from the death of megafauna such as the woolly mammoth, to the extermination of the dodo on Mauritius, to the imminent extinction of the Northern white rhinoceros (with only two female rhinos surviving). This is the result of over-hunting, climate change, habitat destruction and predator and disease introduction.

Because of the sheer number of extinctions caused and threatened by us, we have also observed many hauntingly depressing stories of identifying the last member of a species. For example, we know that the last passenger pigeon named Martha died at the Cincinnati Zoo in 1914. The last Tasmanian tiger (thylacine) named Benjamin died in 1936, neglected in a zoo. These poor creatures who are the last of their kind are called endlings.

A particularly sad endling story is that of a Hawaiian bird species known as the Kaua’i ʻōʻō. They are an extinct species of honeyeater bird that could be identified by their strikingly rich, golden yellow leg feathers. The Kaua’i ʻōʻō were also famous for their flute-like duet songs sang between lifelong mating pairs.

The Kaua’i ʻōʻō became threatened as mosquitoes were introduced to the island of Kaua’i by sailors. The mosquitoes transmitted deadly diseases which decimated the population. To escape the mosquitoes, the birds retreated to higher ground. However, the Kaua’i ʻōʻō were cavity nesters, meaning that they made nests in tree hollows, which are found in fewer numbers at high altitudes. This meant that the birds failed to find nesting grounds and their numbers dwindled further.

The last mating pair was last observed in 1981. Despite ornithologists attempting desperately to protect this pair, they could not locate the female after a devastating hurricane struck the island in 1982. Several years later, ornithologist Jim Jacobi was surveying the Alaka’i reserve when he heard the unmistakable call of the Kaua’i ʻōʻō. He quickly used his tape recorder to record the Kaua’i ʻōʻō’s call. When he replayed the tape to the group, he noticed to his surprise that the male Kaua’i ʻōʻō had flown back towards them. He stared in wonder, then realised: the bird had returned because he had thought it heard another bird calling him; a call it hadn’t heard in however long.

We can still listen to this recording of the Kaua’i ʻōʻō endling. We can hear the clear lack of its duet partner’s call – a deafening silence symbolising the death of a species.

The saddest part of this story is knowing that even though we may never know their name or how their call sounds, countless endlings have died a lonely, quiet death all around the world, marking a full stop to their species’ epic narrative.

You can hear the Kaua’i ʻōʻō endling’s call here:

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

Hexapod

Posted on by Jinavie

Dragons are fantastic creatures of our imaginations, so they do not follow many of the rigid laws of natural science. They breathe unlimited amounts of fire, can endure extreme heat and they can fly despite their massive size. But perhaps the most unrealistic feature of dragons is the fact that they have an unnatural number of limbs.

All vertebrate animals on Earth follow a simple rule: they are four-legged creatures, also called tetrapods. The limbs may have devolved away such as in whales and snakes, but they remain as vestigial structures or still encoded for in the genes. Birds and bats have adapted their upper limbs into wings to fly, but the total number of limbs is still four.

How many limbs does a dragon have? They have four legs that they stand on, but also two large membranous wings like a bat. This means that they have a total of six limbs. The only other animals that share this trait are insects and other mythical creatures such as the centaur and pegasus.

To be a vertebrate with six limbs, a dragon must have evolved from an ancestor separate to Tetrapodomorpha, an ancient fish-like creature with four limbs that is the common ancestor to all four-legged beasts. Alternatively, the wings may not be true “limbs” and be similar to flying lizards that evolved to have a rib jut out with a membrane attached to act as a glider.

Unlike the scientifically inaccurate dragon, a wyvern obeys nature’s four-leg rule. Furthermore, unlike the traditional Western dragon that we have been describing, dragons of the Far East have no wings and four limbs, also obeying the law.

As ridiculous as it may sound, applying scientific principles to our imagination allows us to learn more about how our world works.

Posted in Life & Happiness

Mistake

Posted on by Jinavie

Generally speaking, we live our lives trying to avoid making a mistake. Perhaps it is because we were brought up to do everything as perfectly as possible. Perhaps it is because we fear the consequences. Perhaps it is because we refuse to accept that we are imperfect beings.

Regardless of the reason, we have a constant nagging voice in the back of our minds asking us: “Are you sure you want to do this? What if it’s all a big mistake?”.

This mentality affects our work, our financial decisions, our sense of adventure and even our relationships. Sometimes, we even go as far as not taking any action in fear of screwing it up. The fear of mistakes makes us take less risks and leaps of faith, hindering our ability to live a full life.

But to quote a great captain, Jean-Luc Picard:

“It is possible to commit no mistakes and still lose. That is not a weakness. That is life.”

Life is full of mistakes. No matter how hard we try to minimise risk, life will always find a way to trip you up. Because we are not a time-travelling supercomputer that can see and predict every variable, it is impossible to make no mistakes. Ergo, it is okay to make mistakes, because to err is to human.

In fact, mistakes are not always bad.

A “mistake” such as the singer’s voice cracking on a live performance may make it a more special performance, because it is a sign the singer poured all of their emotion and energy into the song, rather than playing it safe to avoid a mistake.

Columbus discovered the Caribbean because he mistakenly thought that he could reach Asia by sailing due west of Spain.

Everyone has a story of getting lost while travelling and stumbling onto an unforgettable experience that they could not have possibly planned for.

Sometimes, we will look back on our life and realise that what we thought was a mistake back then turned out to be a blessing in disguise, because each and every mistake we made led us to where we are now.

Lastly, we are all the products of billions of years of mistakes. Evolution is fundamentally based on the concept that genetic mistakes during cell division (mutations) allow for diversity of traits. Without mistakes, we wouldn’t even be here.

Of course, some mistakes carry irreversible, dire consequences, such as drinking and driving, or falling asleep while a nuclear reactor fails (Three Mile Island accident). But outside of these, most mistakes in life are something that you can learn something and move on from.

So don’t beat yourself up if you make a mistake.

It’s okay to make mistakes.

We are only human.

Posted in History & Literature

Evolution Of Colour

Posted on by Jinavie

We often take the beauty of colour for granted. How would you explain the colour red to a blind person? With that in mind, how do we know that the colour we see with our own eyes is the same hue that others see? A scholar by the name of William Gladstone came across a similar question in 1858 while studying ancient Greek literature. He noticed that in most literature of ancient times, the description of colour was wildly inconsistent, such as the sea being described as “wine-dark”, the sky being “copper-coloured” and other oddities such as violet sheep and green honey. After further analysis, Gladstone found that white and black were referenced frequently, while other colours were much rarer, with red, yellow and green being the most common colours respectively.

Another scholar named Lazarus Geiger expanded on Gladstone’s research and found that throughout ancient literature – including the Bible, Hindu poems, ancient Chinese stories and Norse tales – described beautiful scenes while omitting a certain detail: a blue sky. It appeared that the colour “blue” did not appear in most languages until a certain point in time, despite the people having lived under the same blue sky that we do now.

Geiger tracked the appearance of different colours in different languages and found a pattern of development. Each language would typically describe white (light) and black (dark) first. The next colour to develop was red, then yellow and green, with blue being one of the last colours to appear. This is likely related to the abundance of each colour (e.g. blood, dirt, vegetation) and the ease of making coloured dye (blue dye is notoriously difficult to make).

This raises an interesting question: if the ancient Greeks did not have a word for the colour blue, could they still perceive the colour blue? Biologically speaking, our eyes are not so different to that of the ancient Greeks. But of course vision is a two-part process – your eye captures the image and then your brain processes the image. Does language have a significant enough impact on how we perceive our world?

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There is a tribe in Namibia whose language does not distinguish blue and green. A study was held where people from this tribe were shown a circle of 12 squares – 11 green and 1 blue. To the researcher’s intrigue, the men and women of the Himba tribe could not tell which square was the odd one out – suggesting that their brain was processing the two colours as identical. However, the Himba language has more words distinguishing shades of green than English. In another study involving a circle of green squares with one square being a slightly different shade of green, the Himba tribe could pick out the different square much more easily than English-speakers.

The so-called “colour debate” is a hotly debated topic, with some arguing that language plays a crucial role in determining our perception of the world, while others state that language is separate to our senses. What did the ancient Greeks see when they gazed up into the sky? If we cannot describe something with words, then does it truly exist? But one thing is clear – things are not always as they seem.

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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

Stockholm Syndrome

Posted on by Jinavie

August 23, 1973 – Stockholm, Sweden. Two men entered a bank and took four bank workers hostage by gunpoint. The police quickly responded by surrounding the bank but could not act due to concern for the safety of the hostages. The stand-off lasted six days until the police finally negotiated the release of the hostages. During this ordeal, a very strange phenomenon was observed. The hostages had grown emotionally attached to their captors, rejecting rescue attempts and even defending their captors after their freedom. It was clear in subsequent interviews that the hostages had bonded with the criminals, supporting their cause and not minding the fact that they were threatened, abused and were made to fear for their lives. In fact, one woman later became engaged to one of the criminals, while another funded the legal fee for their trials.

Psychiatrist and criminologist Nils Bejerot studied this case and coined the phrase Stockholm syndrome to describe the phenomenon of hostages expressing empathy and sympathy to their captors, leading to bonding with and having positive feelings for them. This seems irrational as bonding is perceived as the product of a positive relationship where two people are loving and caring for each other, not threatening their life. This phenomenon has been well-documented throughout history in hostages, domestic abuse victims, prisoners of war and cult members. One study showed that up to 27% of hostage victims showed evidence of Stockholm syndrome in the U.S.

There are a few explanations for the Stockholm syndrome. The Freudian explanation is that the bonding is an individual’s response to the trauma of being threatened. By rationalising that they are in fact on the same side as the captors, the effect of the trauma is reduced as the victim feels less victimised. Evolutionarily speaking, human beings have always been under the threat of being invaded by a neighbouring tribe or country. This often involved the raping and abduction of women by the aggressors. Victims who would resist and fight back would have more likely been killed (along with their children), while those who responded as per the Stockholm syndrome would have been more likely to survive. It has been observed that the Stockholm syndrome is found more commonly in women.

Stockholm syndrome is a very common feature of human society, found in households in the form of battered-wife syndrome, in groups in the form of hazing and basic military training and in the bedroom in the form of bondage and masochism.

Posted in Philosophy

The Significance Of You

Posted on by Jinavie

We are often reminded of how insignificant we are as individuals (or even as a race for that matter) in the grand scale of time and space in the universe. We are but a tiny, invisible dust particle on the map of the universe and we make up a sliver of time in the history of everything. This is a reminder that we should be humble, that no matter how great we think we are, we are nothing in the eye of the universe.

Then again, sometimes it is nice to remember that we are significant. Consider this. For you to have been born, generations after generation of couples have had to produce a child. You are the product of 4 billion years of evolution. 4 billion years of unbroken lineage, from the primordial ooze to bacteria to fish to amphibians to reptiles to rodents to primates. If even a single couple in that chain decided not to have an offspring, you would not be here reading this. Of course, this also puts you under the pressure that you may be the last one in that 4 billion-year chain not to reproduce, but let us ignore that for now.

Now consider the stars. When you look upon the night sky and see the twinkling of a star, what is happening is that photons (light particles) are hitting your retina and triggering a signal that is sent to your brain and interpreted as twinkling. Those photon generated by the star you see have travelled light years through the vast universe until your retinas rudely interrupted its journey. The closest star to us (excluding the sun) is Alpha Centauri, located 4.37 light years away. 1 light year (distance travelled by light in a year) is just under 10 trillion kilometres, meaning that those photons you blocked had travelled at least 41 trillion kilometres – or 41,343,392,165,178,100 metres. All you had to do was exist in a certain location and look up at the sky.

Some might say that you are puny and insignificant compared to this astronomical scale. But another way to think of it is that you effected real change in the universe (even if it was blocking a particle of light). No matter how small you are, no matter how short your life is compared to the history of the universe, you are not insignificant. Chaos theory (better known as the butterfly effect) dictates that even the smallest change in initial conditions can lead to unpredictable, widely diverging outcomes. For all you know, your existence is the difference between the existence of life on a distant planet somewhere.

So never say that you are insignificant. And if evolutionary biology and astrophysics is not enough to convince you, then look around you. The people you have met and interacted with throughout your life are affected by you in one way or another. For example, a compliment you paid in passing might completely change the person’s day. A simple act of kindness you thought nothing of could be recorded in someone’s life book as a life-changing event. Even a smile can make a difference. You are significant.

“If you could only sense how important you are to the lives of those you meet; how important you can be to the people you may never even dream of. There is something of yourself that you leave at every meeting with another person.” ~ Mr. Rogers

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Posted in Psychology & Medicine

Pain

Posted on by Jinavie

Perspective is everything. By changing your perspective, you may discover an innovative solution to a problem, or understand the actions of someone else. But more importantly, your perspectives have direct implications in your life and health.

For example, let us consider pain. Pain is a sensation – an electrical signal in response to a noxious stimuli that is causing damage to your body. It is a warning system that screams to the brain that something is wrong. To boil down the complex physiology of neurotransmission, essentially imagine the system as an electrical circuit. If something damages tissue, like a knife slicing through flesh or a clot blocking off oxygen supply to the heart, the pain “switch” is activated, a signal is sent to the brain, and it is interpreted and “felt” by the brain as pain. Because your brain needs to interpret the signal, pain is essentially subjective. If you are distracted or in a good mood, you will feel less pain compared to when you are distressed and focussing on it. The same stimuli can be handled completely different by every person, making pain extremely complicated and difficult to assess in a medical setting. Pain scales may be used to try objectify the level of pain, but this is still very crude.

UCEM Pain Scale

One way or another, pain is technically all in your head. That is not to say that pain is not real – that would be an insult to sufferers of chronic pain. But your perspective, way of thinking and frame of mind can make a significant difference to the amount of suffering the pain causes. This is not just an overly-optimistic view of the world that everything can be fixed with optimism. There are real physiological systems in place to alleviate pain when you are happy. These chemicals are called endorphins – so named because they are so potent that they match the effect of morphine (endo(inside) + morphine). This natural painkiller is released in response to pain, but can also be stimulated by having fun and being happy. Laughter is literally medicine.

Not only that, but by being in a good mood, you become more resilient and “distracted from the pain”, allowing you to bear the pain more easily. A woman going through childbirth suffers quite possibly the most extreme level of pain a human being can experience, but the prospect of seeing their newborn child (and probably finally ending their pregnancy) and the loving support of their spouse, family and friends keep them pushing onwards. Even though the noxious stimuli of stretching is real, the brain can choose to downplay how much pain it thinks it should feel with these positive factors.

Although it may not be able to make your pain magically disappear, never underestimate the power of positivity, laughter and happiness. Perhaps that is why the emotion of happiness was evolved – to alleviate the misery and pains of living in this world. To survive.

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Posted in Science & Nature

Lizard People

Posted on by Jinavie

What would the world be like if the dinosaurs had not gone extinct? In 1982, palaeontologist Dale Russell proposed a thought experiment regarding the possible evolutionary path of a species called Troodons. The Troodons were small, bird-like dinosaurs from the later periods of the reign of dinosaurs. They grew up to 2.4m in length and about 50kg in weight, standing on two slender hind legs. The most interesting feature of Troodons was their very large brain – six times larger than any other dinosaurs relative to their body weight. This would have most likely allowed the Troodons to be quite intelligent relative to other species, allowing it to utilise crude tools such as rolling a boulder off a cliff.

Russell believed that had the Cretaceous-Paleogene extinction event did not happen 65 million years ago (when a giant meteor struck Earth), the Troodons could have evolved in a path similar to humans, expanding their brain size and using intelligence as a tool of survival. Although its brain size was substantially lower than that of a human, he believes that through evolution, by the present its brain would be the size of a modern human’s. He also believed that evolution would have shaped the Troodons into a “dinosauroid” form, much closer to the shape of a human being. The Dinosauroid (nicknamed lizard people) would have had two fingers and a thumb, large eyes, no hair, internal genitalia (like reptiles), no breasts and a navel (the placenta is instrumental in giving birth to large-brained offspring). Their language would probably have sounded like a bird song.

Given the history of Homo sapiens and our competition and ultimate demise of similar sapient species, it is unclear whether we would have won the survival war against the Dinosauroids, or whether we would have even had the chance to evolve to our stage, as mammals rapidly filled the niche after dinosaurs were wiped out. There is much criticism of Russell’s thought experiment of the Dinosauroid being “too anthropomorphic” (too human-looking), but as suggested in the book K-PAX by Prot, perhaps the humanoid form is the most efficient natural design for an intelligent life form. Realistic or not, it is a fascinating projection of a world that could have been.