Tag: how

Jellyfish Stings and The “Pee on it” Myth

By Anupum Pant

I haven’t been ever stung by a jelly fish, but from how Destin says it in the video, and other people I’ve seen getting bitten, tells me that it is something no one would want to experience in their life. If you did not know, the sting is awfully painful.

A jelly fish uses venom, not poison. They are two different things. Which means that a jellyfish stings you and uses extremely tiny hypodermic needle like things to inject toxins in your body.

But doesn’t jellyfish seem like a bunch of jelly floating around with no visible prickly parts? how does something so soft actually go about inserting something sharp into your skin?

Turns out, on the surface of those long tentacles these fish have, there are microscopic organelles called nematocysts which it uses to sting you. Even a tiny brush with those tentacles can trigger them. The more interesting part is that these tiny needles act very fast, and like I said, they are also very tiny. So, to see them you need a really high frame-rate camera attached to a microscope.

That is exactly what Destin does in the video below. It’s fascinating to see those tiny stingers do their work so fast under a microscope. Not many get a chance to see something like this.

Just FYI. In case you ever end up getting bitten by a jellyfish, please don’t ask your friend to pee on it. There’s a word going around that this helps, but in reality it doesn’t. In fact it can make it worse. Instead try washing it off with sea water. And then use a credit card to scratch the sting to remove any nematocysts stuck in your skin.

Don’t believe me? Please watch this…

Benford’s Law Will Make You Wonder For a While

By Anupum Pant

Benford’s law is a fairly simple law to grasp and it will blow your mind. It deals with the leading digits of numbers.

So, for example, you have the number 28 – The leading digit for it would be 2. Similarly, the leading digit for 934 would be 9. Just pick the first digit. Now…

In a data set you’d say – it is common sense to assume that the probability of leading digit one (1) appearing would be more or less equal to that of leading digit nine (9).
As there are 9 possible leading digits, you’d think that the probability of each leading digit would compute to something around 0.11
You’d imagine that it would be normal to assume a nearly straight graph of probability vs. leading digit. But this isn’t true.

Benford’s law says

Your common sense fails. What actually happens is that the likelihood of 1 appearing as the first digit in a data set is around 0.3
For the following digits, the probability keeps decreasing. And the following graph appears. You’ll see that the numbers rarely start with nine!

Benford2

When does it work?

This counter-intuitive result applies to a wide variety of natural data sets. It works the best if your set spans quite a few orders of magnitude. Natural set of data like stock prices, electricity bills, populations, which could range from few single digit values to several digits work the best. Other data like the heights of people doesn’t work because it does not span “quite a few orders of magnitude”. Also, artificially tampered data fails to comply because the person who tampers does the same mistake everyone does. Therefore, Benford’s law is also used to detect frauds in data.

Example:

  1. Count the number of data points in a data set which have the leading digit 1 and write the number next to the number 1 in a table.
  2. Then, keep repeating it for all the numbers 2, 3, 4 and so on.
  3. Calculate the probabilities for each. In the end you’ll be left with a table that would look something like this. (Probability = Number of Data Points for that  digit / Total Data Points)
Leading Digit Digit Probability
1 0.301
2 0.17
3 0.125
4 0.097
5 0.079
6 0.067
7 0.058
8 0.051
9 0.046

How does it work?

Watch the  following video for the explanation:

Try it yourself: [Kirix]

Valporate – Performance Enhancing Drug for Perfect Pitch

By Anupum Pant

Today we find out if it would be a good idea to impress your friends during the next gathering by hacking your brain with pills to learn a rare ability fairly quickly. But first, pay attention to the following jargon.

Perfect pitch

Perfect pitch is an exceptional ability among few gifted humans that enables them to recognize and re-create the pitch of a musical note instantly without the help of any external reference. There have been no cases of adults learning this ability by practice. However, pseudo absolute pitch can be learnt with great practice and only retained through regular use.

Brain plasticity

Learning to recognize musical notes, or any other ability for that matter can be reasonably easy at an early age due to a brain’s plastic state. The brain’s ability to change and adapt as a result of experience is far better at younger ages. As people age, they lose the ability to learn like kids.

For instance, picture the rate at which infants learn language. By the time they turn 2 – 4 years old, they start using thousands of words. Try learning a new language at the age of 35. It is tough.

However, a new research suggests that this state of brain can be recovered by using drugs. One such drug, according to Dr. Takao Hensch is Valporate.

Is Valporate a Performance Enhancing Drug?

No! it is not a performance enhancing drug. Valporate or Valporic acid is a drug sold under the common names – Depakote, Depacon and Stavzor. For several years it has been used to treat various disorders from migraines to bipolar disorder. It is a chemical substance that can cross the blood–brain barrier. As a result, it has the power to affect an individual’s perception, mood, consciousness, cognition, and behavior.

Dr. Takao Hensch, a Harvard University professor, recently published a study which tested the effects of Valporate on 23 healthy male subjects for two weeks. None of them had a musical experience. During this period they were trained in music. At the end of this study, researchers found that these 23 men did remarkably better than an average adult would do, at perfect pitch tests.

In the future

He thinks, may be 10 years down the line, this drug could be used to enhance other learning abilities like language learning among adults, by changing the state of their brains.

Presently, studies on how the brain changes at cellular level when this drug is taken are underway. Also, Dr. Hensch thinks that humans have evolved to experience these learning stages for a reason. If it is okay to mess around with it, is still being studied. At this stage, trying this out at home can be extremely risky. It would be wise for us to wait for scientists to come out with a comprehensive study on the effects of this drug.

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Raining Frogs and Fish

By Anupum Pant

Raining cats and dogs is a bit unlikely, but there is nothing wrong about saying, “it is raining frogs and fish”. It happens more often than you think. So, don’t be alarmed if one day you wake up and find fish on your terrace.

When we talk about rain, the one place in India which stands out is Kerala. As we’ve seen in a previous post that Kerala has seen red rains, it has also seen raining fish. This isn’t a joke. On February 12, 2008, people actually saw fish falling down from the sky.

Not just that. I’ve seen reports of water birds, tomatoes, coal, and even a boats falling from the sky.

Raining Animals

After a few moments of awe, when you look at the occurrence of raining animals with the science microscope, you’ll find that it is not something very extraordinary. In fact, there is a whole Wikipedia page on raining animals. It turns out, several places around the world have experienced raining frogs, fish, spiders, worms etc. And as always, science has an explanation for it.

How does it happen?

Water Sprouts: When tornadoes move on land, they can pick up trucks, houses, trees and what not. They suck up several things from the ground and cause total destruction along the path they travel. But, when such storms travel on water, they suck up water, fish and of course, frogs.

This experiment proves how a low pressure can pick up things. – [Experiment]

These things can stay up with the storm for a long time. And eventually when the storm comes on land and weakens the animals may drop down with rain. As a result, we see fish and frogs raining from the heavens.

Ambergris – Whale Vomit Can Make You Rich

By Anupum Pant

It is yellow/gray, smells really bad and can make you rich [image]. Ambergris, or commonly known as whale vomit is a waxy, hard, flammable substance that sells for several thousand dollars a pound. Although it is known as whale vomit, it is usually excreted (not vomited) by the sperm whale. It is formed by the lumping of Bilary Secretions in a whale. They can’t be digested and are often excreted by whales. These lumps can float for years and might get washed to the beach or are found in whale abdomen.

A fresh lump would be black and slowly a lighter colored coating forms on it with age. Generally, lighter colored pieces have a sweeter smell because they have cured in the ocean for a longer time.

What makes it so costly?

Firstly, it is rare to find a lump of Ambergris. Secondly, as this substance ages, it leaves the stink and starts emitting a sweet, musky odor. Not all people like this smell. Other than its unique scent, the perfumes made of this substance last much longer than other scents that tend to evaporate. Both these reasons make it a substance in high demand.

Although the scent can be mimicked by using chemicals, there is nothing like using the real substance. Thus, whale vomit will always carry a premium price.

This year, Ken Wilman, while walking his dog on the beach, spotted a 6 lb lump of whale vomit that turned out to be worth £100,000.
Note to self: So, the next time you are going out for a walk on the beach, take your dog with you. And go on walks more often.

[read more]

Why Do Bad Eggs Float?

By Anupum Pant

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Instead of cracking up an egg which has been stored for a long time, to end up disgusted by the ‘rotten egg smell’, or the smell of a gas called Hydrogen Sulfide, a simple and a fairly well known way to check if an egg has gone bad, is to drop it in a glass of water and see if it floats. I found out about this first, from an article written at Frugal Living, and spent some time to confirm its claims – Bad eggs float.
If you take my word for it (you should!), it really does work. The article describes this three-point test to find out if an egg is good to eat.

  1. If the egg sinks and lies on its side, it is a fresh one. It is good enough to be eaten.
  2. If it sinks and stands up on a point, or is at an angle, it is good enough. You can still use it up for making hard-cooked eggs or bake it.
  3. But, if an egg floats, it needs to be discarded.

Why does this happen?

To understand, you’ll have to think of a chick – a young chicken.

Poor Chicks: Before chickens come out of the egg, they develop lungs and need oxygen to breath. Sitting inside a sealed egg, with no cords attached, for the chick to survive, oxygen has to come in from somewhere. For that, let us look inside.

Egg Science: The outer shell of an egg has two membranes under it. When an egg is laid, it is warm and starts cooling which contracts the inner part of the egg more than the shell and pulls the two membranes apart. As a result, air gets trapped in between the membranes (not enough air initially for it to float).

How does the air come in? The shell of an egg isn’t as simple as it looks. It has about 7000 tiny pores in that shell which let the air pass in and let the carbon dioxide pass out of it. This is how the chick breathes. And the reason, eggs boiled in colored water during Easter, get colored from the inside.

So, as there are pores present in the shell, bacteria enter the egg and start decaying the biological matter inside. This produces a smelly gas (and other gases too), Hydrogen Sulfide (also present in smelly farts). The gases from this decomposition, and the air from outside, keep increasing in volume as time passes.

Corollary: This is exactly what explains these floating bad eggs – Greater the amount of gas inside, older is the egg and the better it floats in water.

Side note: Egg shells and the two membranes inside have the ability to stop the invasion of micro-organisms and bacteria, but over time bacteria manage to enter.

A Bat’s Inverted Sleep Position

by Anupum Pant

I have written about sloths in the past. In that post, we appreciated the way their bodies are engineered to stay inverted for most of their lives. It turns out, a bat’s body is designed (rather evolved) in a similar way, which enables them to relax and sleep upside down. In this post, I would like to discuss – why did they evolve this way and how do they do it?

If you are interested to know more about bats, you will definitely like this post from the archives. [Bats can See]

How can bats manage to sleep like this?

Humans sleep in a horizontal position, cows sleep with their eyes open, horses sleep in a standing position, and of course, bats sleep in an inverted position. What makes an animal sleep in the position they do, is basically their anatomy – the way their bodies are designed. While sleeping upside down might seem as an anomalous behavior to us, it is a normal position for the bat’s body. Like we don’t exert energy when we are lying down, bats’ bodies don’t consume extra energy for hanging down like that.

Firstly, a bat’s claw is like a hook. A better way to understand why this helps is, to look at a converse behavior – the way a human hand works. We use up energy to contract tens of muscles and make up a hook with our fingers; this is not a normal state of our hand. Also, our relaxed hands are open where we don’t exert any energy and we sleep with our hands in that position. A bat’s claws are designed in a completely inverse fashion; they are hooked in the normal position. They don’t take up energy to make them into hooks, they are like that. And they sleep like that – which enables them to hang without using energy.
So, unlike our hands, a bats’ closed fist is their relaxed position. They have to contract tendons and use energy to open them up. This anomalous talon design allows them to hang in a relaxed position.

Bat's Talons - Normal position

Secondly, unlike every other bird, a bat can’t take off from an upright position, or from the ground. They have to be inverted to start flying. This is because they have relatively weaker wings which can’t make them fly from a stationary position. Think of an X-51A Waverider, which has to be carried on a B-52 plane and dropped down to start a flight. They drop down for a very small amount of time and beat their wings vigorously to start a flight. Since, they have to wake up inverted to go flying and catch a meal, they go to sleep like that.

Why did they evolve this way?

They’ve evolved this way to simply stay away from the predators:

  1. By hiding up in a place where not many predators would look – under a bridge, roof of the cave and dark tree canopies. Also, at places like these, they don’t have to compete with other birds for a place.
  2. And by escaping quickly in case of an attack by attaining instant flight [see above].

Why is a Metal Plate “Colder” Than a Plastic Plate?

by Anupum Pant

No, it isn’t!

What is Cold?

According to the dictionary, a body at a relatively lower temperature, especially when it is compared to the temperature of a human body is described as a colder one. So, any object below the normal human body temperature – about 37 degrees Celsius – is a cold thing. But wait a minute!

When you touch an object, what does it tell you about the temperature of the object? Can you really judge if it is a cold one or a hot one? Unfortunately, our bodies aren’t thermometers, we are not so smart when it comes to judging the temperature. Consider the following case.

A book and a steel plate kept in the same environment for a long time attain the same temperature eventually (it is called thermal equilibrium). This can be checked by using a thermometer on both the objects. But, when people are asked to touch a metal plate and a book, they find the former to be much cooler. You can try this out yourself by touching different materials around you. You’ll see how some things ‘feel colder’ while the others feel warmer. A YouTube channel Vertasium conducted a social experiment to record this on camera. See the video below:

There is no cold – only heat

So, in the video, ice melts faster, if kept on steel plate than on a plastic plate, even when the steel plate ‘feels colder’. Common sense dictates that the colder thing is supposed to sustain the ice block for a longer time, just like your refrigerator does. So why does the opposite happen?

A better way to understand this ‘contradiction’ (not really a contradiction) can be this:

According to thermodynamics, simply put, everything has heat in it. So, even a cold ice block has some amount of heat stored in it (say, around 273.15 Kelvin or 0 degree Celsius). When one object comes in contact with other object, it loses or gains heat till their temperatures get equal or till they attain ‘thermal equilibrium’. Which object loses heat and which one gains it, is decided by their relative temperatures. In case of ice and steel, ice has a lower temperature than steel (assuming it isn’t already freezing out there). Therefore, here, ice gains heat from steel till they attain the same temperature and ice melts.

Side note: The ice is also in contact with a relatively ‘hotter’ atmosphere. Hence, it gains heat from there also. In this case, we are only concerned about the steel and ice interaction.

Why does it melt faster on steel?

There is a particular property which depends on the kind of material and is called thermal conductivity. This is the parameter which decides which objects lose heat quicker and which ones do it slower.

Here, for instance, steel has a higher thermal conductivity than plastic. Hence, the steel plate gives away heat to the ice block faster than a plastic block does. As a result, ice melts faster on a steel plate than on a plastic one.

Incidentally, this effect can also be used to explain why one plate feels colder than the other, in our hands. Think of it like this, the ice is replaced by our hand. So, a steel plate, due to its better thermal conductivity, draws heat faster from our hand than a plastic plate. This makes us feel that the steel plate is colder than the plastic one.

As checked by a thermometer, both the plates have the same temperature, our bodies are only fooled into believing that the thing we feel is temperature; it isn’t. None of the plates is actually colder than the other (according to the dictionary – see first paragraph). We don’t feel the temperature. What we feel is actually the rate of heat being drawn away from our hand. Faster an object draws heat, the colder it feels.

The Purpose of Sleep – Theories

by Anupum Pant

Did you know?

  • You can live longer without food than you can live without sleep.
  • On an average, a person sleeps for 1/3rd of his life. That means if you are 30 years old, you’ve slept for 10 years already.
  • The world record for the longest span remaining awake is 11 days. The record was set by 17-year-old Randy Gardner in 1964 when he was awake for 264 hours and 12 minutes. (Don’t try this)
  • If it takes you less than five minutes to fall asleep then very likely you are sleep deprived. It should take about 10 minutes normally.
  • You can lose up to 2 grams every minute while sleeping. That comes to about a lost Kilogram at night.

What is Sleep?

Everybody sleeps. On an average, everyday, a bat sleeps for 15 hours while just 3 hours are enough for a Horse to feel rested [How much do animals sleep – chart]. Dolphins can sleep with half of their brains active and even the smallest of worms need sleep. But, till date, scientists haven’t been able to reach a consensus on why we actually do it?

Sleep can be understood as a life sustaining activity. It can be compared to another of our important activity – eating. These strongest of the human urges – eating and sleeping – serve a nearly common purpose – quell the urges; just as eating relieves hunger, sleeping relives sleepiness.

While it is true that we may have not been able to spot the primary purpose of sleep, years of research hasn’t gone wasted. With time, we have learnt a lot more about sleep than we used to know 50 years back. There have been hundreds of practical and impractical theories on why we sleep. I’ve mentioned a few of the realistic ones here.

Purpose of Sleep – Theories

Inactivity Theory:

According to this old theory, sleep evolved out of the need to be safe. It suggests that inactivity at night is an adaptation that serves as a survival mechanism. It functions as an activity which would keep an animal safe during the time it is most vulnerable e.g. Humans are vulnerable at night because they don’t see well in dark.

This theory is easily countered using the argument: Being conscious and still, is much better way to stay safe than lying unconscious and still.

Energy Conversation Theory:

It suggests, the main function of sleep is to reduce the demand and consumption rate of energy at times when searching for food isn’t an efficient option. Some believe, that this theory is a part of the inactivity theory. But, unlike the inactivity theory, this theory has been bolstered by various experiments which prove that the consumption of energy is reduced when an organism sleeps.

Restorative theory:

It explains sleep as an opportunity for a body to rejuvenate in terms of muscles, tissues, proteins, cells and growth hormones. Also, during sleep, the body clears an accumulated molecule called adenosine from the system, and makes us feel alert when we wake.

A recent study also seems to support the restorative theory in a fresh manner. It says, brain accumulates toxins [like beta amyloid] while it is awake. The concentration of such toxins keeps increasing during waking state. The study observed an increased activity of spinal fluid being pumped into the brain in rodents (hasn’t been studied on humans yet). This spinal fluid functions as a medium to pump out toxins from the brain. This theory could be a breakthrough in the study of causes and prevention of Alzheimer’s as it is known that toxins like beta amyloid cause the disease in humans [How beta amyloid causes Alzheimer’s].

Brain Plasticity Theory:

According to this, sleep plays a critical role in brain development. Infants (age when the brain develops the most), for example, sleep for about 13 – 14 hours every day. On the other hand, the poor ability to learn and perform tasks due to the lack of sleep explains the role of sleep in adults. Since, It has been proven that brain is highly active during sleep, this theory remains the most plausible one in being able to state one of the functions of sleep.