SCI-ART LAB

Science, Art, Litt, Science based Art & Science Communication

Krishna: ‘Beautification’ is what we attribute to these things based on our perception.

But eyebrows’ and eye lashes’ primary function is providing safety - to serve as the first line of natural defense against airborne debris and other hazards getting into the eyes.

Eyelashes are a first line of defense for your eyes, keeping airborne dirt, dust, lint and other debris from reaching the delicate eye tissues.

With eyes open, eyelashes catch some airborne debris, but when closed, eyelashes form a nearly impenetrable barrier against foreign irritants in the eye. That is why eyelashes are also incredibly sensitive.

How sensitive? Reach up and touch the very tip of one of your eyelashes. No matter how lightly you touch them, you can sense it immediately. Touching your eyelashes also triggers your body’s blinking reflex, which occurs to prevent debris or dirt from getting any closer to the eye itself. The blinking reflex is why it can be challenging to keep your eyes wide open while inserting a contact lens or applying makeup.

What purpose do eyebrows serve in eye health?

Though they’re positioned farther away from delicate eye tissue, eyebrows serve an essential purpose. The next time you’re outside in the hot summer sun and sweat starts dripping down your forehead, notice what happens. The eyebrows are positioned along the brow bone to help channel sweat and other liquids away from your eyes. Thanks to eyebrows, sweat flows down the side of your face so it won’t go directly into the eye socket.

Whether it’s sweat, rain, or shower water, eyebrows do a great job of re-routing liquids away from the eyes. Both the shape of your eyebrows and each individual hair within the brow play a role in this function.

Eyebrows serve another functions: communication through facial expression

Based on the above answer ..... another person asked this question ....

Q: A small doubt Ma'am, how does evolution know where to grow eyebrows exactly (to channel sweat) or is it completely random coincidence?

Krishna: :) How does evolution know how and where to act?

Well when organisms are evolving, they face certain problems and challenges. Like when the eyes are developing to gain sight, when something falls in the eyes, the eyes get irritated. Water falling in the eye makes your sight somewhat blurred. The brain or the nervous system detects this as a problem. Something has to be done to overcome these problems.

Evolution takes notice of this.

Mutations take place in cells all the time. Evolution tries to retain some of these important ones that are beneficial. For instance, if a mutation occurred to grow eyebrows and if these eyebrows are stopping sweat from falling into the eyes, evolution identifies it as beneficial one and tries to retain it.

Mutations occur in the nearby cells to overcome these challenges.

Human evolution took place as new genetic variations in early ancestor populations favoured new abilities to adapt to environmental change and so altered the human way of life.

One mechanism that drives evolution is natural selection, which is a process that increases the frequency of advantageous alleles in a population. Natural selection results in organisms that are more likely to survive and reproduce. Another driving force behind evolution is genetic drift, which describes random fluctuations in allele frequencies in a population. Eventually, genetic drift can cause a subpopulation to become genetically distinct from its original population. Indeed, over a long period of time, genetic drift and the accumulation of other genetic changes can result.

Mutations are random. Retaining the important ones is selective.

Q: What would happen if the North Pole were to melt?

Krishna: It would be a great disaster!

You will encounter all these consequences:

1. Extreme weather events: Since poles are covered in white snow and ice that reflect heat back into space, they balance out other parts of the world that absorb heat. Less ice means less reflected heat, meaning more intense heatwaves worldwide. But it also means more extreme winters: as the polar jet stream—a high-pressure wind that circles the Arctic region—is destabilized by warmer air, it can dip south, bringing bitter cold with it. If the Arctic continues to warm – and at alarming rates at that – we could experience more extreme weather events such as droughts, heat waves, heavy rainfall, and hurricanes and tropical storms.

2. Drowning of coastal areas: As the ice melts, seas’ and oceans’ water levels rise drowning low lying coastal areas and displacing people living there.

3. Increased food prices: Polar vortexes, increased heat waves, and unpredictability of weather caused by ice loss cause significant damage to crops on which global food systems depend. This instability means higher prices for you and growing crises for the world’s most vulnerable.

4. Effect on wild life: When there’s less sea ice, animals that depend on it for survival must adapt or perish. Loss of ice and melting permafrost spells trouble for polar bears, walruses, arctic foxes, snowy owls, reindeer, and many other species. As they are affected, so too are the other species that depend on them, in addition to people. Wildlife and people are coming into more frequent contact – and often conflict – as wildlife encroach on Arctic communities, looking for refuge as their sea ice habitat disappears.

5. Release of more green house gasses into the atmosphere: Arctic ice and permafrost—ground that is permanently frozen—store large amounts of methane, a greenhouse gas that contributes to climate change. When it thaws, that methane is released, increasing the rate of warming. This, in turn, causes more ice and permafrost to thaw or melt, releasing more methane, causing more melting. As we lose more ice more quickly and see more rapid permafrost melt, we will start seeing the worst climate change predictions come true.

6. Seas routes change: As the ice melts more sea routes will open.

These are some of the predictions based on our previous experiences.

But who knows what else is in store for us?

Q:  How much mercury enters the body and causes death?

Krishna: How much mercury enters the body? It is how much you inhale or take orally.

How much mercury is necessary to cause death?

According to WHO ….

Elemental and methylmercury are toxic to the central and peripheral nervous systems. The inhalation of mercury vapour can produce harmful effects on the nervous, digestive and immune systems, lungs and kidneys, and may be fatal. The inorganic salts of mercury are corrosive to the skin, eyes and gastrointestinal tract, and may induce kidney toxicity if ingested.

Neurological and behavioural disorders may be observed after inhalation, ingestion or dermal exposure of different mercury compounds. Symptoms include tremors, insomnia, memory loss, neuromuscular effects, headaches and cognitive and motor dysfunction. Mild, subclinical signs of central nervous system toxicity can be seen in workers exposed to an elemental mercury level in the air of 20 μg/m3 or more for several years. Kidney effects have been reported, ranging from increased protein in the urine to kidney failure. High-level exposure to methylmercury is known as Minamata disease. Methylmercury exposure in children may result in acrodynia (pink disease) in which the skin becomes pink and peels.

The U.S. Food and Drug Administration (FDA) has set a limit of 1 part per million of mercury in fish for human consumption.

For methylmercury, the US Environmental Protection Agency (US EPA) has estimated a safe daily intake level of 0.1 µg/kg body weight per day.

But ….

Symptoms depend upon the type, dose, method, and duration of exposure.

Forms of mercury exposure include metal, vapor, salt, and organic compound.

The toxicity of mercury depends on its chemical form, and thus symptoms and signs are rather different in exposure to elemental mercury, inorganic mercury compounds, or organic mercury compounds (notably alkylmercury compounds such as methylmercury and ethylmercury salts, and dimethylmercury). The sources of exposure are also markedly different for the different forms of mercury. For alkylmercury compounds, among which methylmercury is by far the most important, the major source of exposure is diet, especially fish and other seafood. For elemental mercury vapour, the most important source for the general population is dental amalgam, but exposure at work may in some situations exceed this by many times. For inorganic mercury compounds, diet is the most important source for the majority of people. However, for some segments of populations, use of skin-lightening creams and soaps that contain mercury, and use of mercury for cultural/ritualistic purposes or in traditional medicine, can also result in substantial exposures to inorganic or elemental mercury.

While it is fully recognised that mercury and its compounds are highly toxic substances for which potential impacts should be considered carefully, there is ongoing debate on how toxic these substances, especially methylmercury, are. New findings during the last decade indicate that toxic effects may be taking place at lower concentrations than previously thought, and potentially larger parts of the global population may be affected. As the mechanisms of subtle toxic effects – and proving whether such effects are taking place – are extremely complex issues, a complete understanding has so far not been reached on this very important question.

Q: “Without consciousness there can be no physics, without an observer there is nothing to observe.” Your comment please.

Krishan: Science is independent of human mind. Science exists apart and independent of the human condition and humanities.

For example, E=mc2 is an eternal condition and did not require the mind of man to understand it before it sprang into existence.

Einstein asked: Is the Moon There When Nobody Looks?

The answer is it is there. Moon existed even before life originated on Earth. There are several worlds out there where planets and their satellites exist even if there isn’t life to observe them.

Q: Is this universe a living organism?

Krishna: To answer this question, first we will have to define what a living organism is.

There is currently no consensus regarding the definition of life. One popular definition is that organisms are open systems that maintain homeostasis, are composed of cells, have a life cycle, undergo metabolism, can grow, adapt to their environment, respond to stimuli, reproduce and evolve.

Even if we take all these parameters into account, the universe as a whole cannot be considered as living because the inanimate part of it is more than the living part. The universe doesn’t do all these things mentioned above.

Then how can you consider it as living?

However, some people come up with strange ideas and explanations. Like this one:

The universe: inanimate space or a living organism?

Q: What is the scientific explanation behind flamingos changing their colour from white to pink as they age?

Krishna: The name flamingo means in Portuguese/Spanish - actual word ‘flamengo’ -  ‘flame-coloured’ which has a  relation to their vibrant feathers, however, they aren’t actually born pink. Instead, when flamingo chicks hatch they have a dull grey or dirty white colouration to their feathers. Young flamingos flaunt grey/white colour feathers and only develop their pinkish hue after delving into a diet of brine shrimp, crustaceans and blue-green algae – food that would likely kill other animals.

Pink and orange flamingos Image source: google images

Flamingos tend to live in inhospitable, relatively remote wetlands – lakes so alkaline in pH it could burn human flesh off the bones. Within this water, however, is an untapped resource of food like crustaceans, cyanobacteria and diatom algae which are actually re-orange in colour due to a chemical known as beta carotene. All of these foods can be dangerous to many other animals as they contain toxic chemicals called carotenoids which are also found in carrots, sweet potatoes and spinach.

So, how are flamingos able to eat these foods without falling seriously ill? Thanks to their specialised metabolism, the birds are able to process these harmful chemicals in the liver, breaking them down into functional components and pigments. It’s these pigments that eventually stain a flamingo’s feathers.

Once eaten, enzymes in the flamingo’s digestive system break down the beta carotene and the red-orange pigments are absorbed by the fat in its liver. These fats are then deposited in the flamingo’s feathers and skin as it grows. As their diet is almost exclusively from sources rich in beta carotene, flamingos gradually become pink. 

The colouration of flamingos can vary because carotenoid levels in algae and crustaceans also vary across the world. Flamingo species found in the Caribbean are often bright red or orange, while those in drier areas tend to be paler pink in colour. Without a high enough concentration of beta carotene-rich food, the pink feathers would moult away and new paler feathers would start to grow. Their skin, mucous membranes, egg yolks and even fat are stained pink and similar colours like orange.

Although the sight of a colourful flamingo is a familiar one, there are a number of ways they can lose their distinctive hue. Carotenoids themselves can bleach in the sun, something the flamingo species Phoenicopterus roseus combats by preening themselves directly with pigments secreted from their glands, giving their feathers a lustrous pink shine.

 It’s also worth noting this only works with pink pigments – you can’t feed a flamingo blue food dye and hope it turns sapphire.

Interestingly, while flamingos are pink primarily as a by-product of their diet, their colour takes on a special significance during mating season. As a flamingo, the pinkier you are, the healthier and better quality you are – it’s a direct reflection of how good you are at foraging. And you can use that to attract a mate in a courtship ritual.

Watch this beautiful court ship dance of flamingos

The flamingos will pair off within their group based on who’s the best dancer and who has the greatest colour.

Flamingos are also one of few birds that feed their young with crop milk. This is different from the milk produced by the mammalian species, the crop milk produced by flamingos is a highly nutritious bright pink secretion made in an adult’s throat, and is so densely packed with carotenoids that when breeding season is over both male and female parents often appear white, losing the pink colouration from their feathers.

Despite numerous reports of blue flamingos appearing online, there is no evidence to suggest these are anything more than internet hoaxes. However, there have been a number of sightings of a rare black flamingo in Cyprus. It is thought that it suffers from a pigment condition called “melanism”, causing an overproduction of melanin making it black.

Watch this rare black flamingo ....

 

However, not all flamingos will be involved in the dancing ritual – and many of these birds won’t be pink at all. Flamingos – both male and female – can lose their pink pigments outside of breeding season. That’s because the breeding is so intensive and so much of their food is used for their chicks.

The collective noun for flamingos going about their everyday activities such as feeding, is a ‘stand’. However, when in the midst of their courtship dance, a group of flamingos are known, amazingly, as a flamboyance.






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