Viswanathan K's Thoughts

Surface vibrations. Vibrations that travel along the surface (obviously). Some question how they are different from sound – aren’t both vibrations? Yes, they do have their similarities. But there are also differences, which is why Ed Yong dedicates a chapter to surface vibrations in Immense World , albeit a small one. The first difference is that sound vibrations are in the same direction in which sound travels; whereas surface vibrations are perpendicular to the direction that the vibration travels.  The bigger difference is that, until recently, scientists focussed only on sound but not surface vibrations, so they didn’t know much of how surface vibrations are used by different creatures.   Take the spider web. We think of it as a trap. Yes, it is that, but it is also a “surveillance system”, extending the spider’s senses well beyond its body. The spider can sense vibrations in the web. They can differentiate the vibrations caused by rustling wind from a leaf that fell to a str

Not surprisingly, when the imprisoned opponent of Putin, Alexei Navalny died/killed in prison, there was an outpouring of criticism from the West. Self-righteous proclamations of “Western values” have followed. Take this one by Andrew Sullivan as an example: “(Navalny) represented the core principles of the West; and they are worth prudently defending abroad as well as at home. In Navalny, you see a commitment to empirical truth over ideological lies; to transparency over corruption; to courage over brute force; to humor over power; and to freedom over tyranny. ”   Really? The West cherishes these things abroad? Didn’t they support the massacre in East Pakistan/Bangladesh in 1971? Haven’t they always supported dictators in the Middle East, including one Saddam Hussain (until he invaded Kuwait)? Such love affairs of the West with brutal dictators have been true for long, best captured by Franklin D Roosevelt’s infamous line: “(Dictator X) may be a son of a bitch, but he's ou

Instinctively, we think touch is based on contact. Not entirely true, explains Ed Yong in Immense World – there’s a more important aspect than contact: “These incredible feats are possible through movement. If you rest a fingertip upon a surface, you can get only a limited idea of its features. But as soon you’re allowed to move, everything changes. Hardness becomes apparent with a press. Textures resolve at a stroke.” As you run your fingers over a surface, they hit the tiny peaks and troughs and set off vibrations in the mechanoreceptors at their tips.   At the tip of its snout, the star-nosed mole has many pairs of hairless appendages. It uses them to touch things around itself. Alive or dead? Food or ignore? It does these movements at an insane speed. In the time it takes to blink our eyes, the star-nosed mole can probe, identify and swallow its food. “Light may be the fastest thing in the universe, but light sensors have their limits, and the star-nosed mole’s sense of

At a time when computers were still as large as rooms, worked on vacuum tubes that would notoriously conk out all the time, when the concept of software programs was still in its infancy (you had to re-wire the machine physically for every new activity), Alan Turing was already thinking way ahead. Could machines become intelligent, he wondered, in 1947.   He pointed out that humans, in logical fields like maths, make mistakes. But with machines, we have zero tolerance for errors. If we continued with that approach, then machines can never become intelligent, he said in a lecture: “If a machine is expected to be infallible, it cannot also be intelligent.”   Another mathematical genius, John von Neumann, shared Turing’s view. By 1952, the idea of software (instructions given to a computer to do different things, without needing to re-wire the machine) was not all that uncommon. With humans, he said, we accept that making mistakes (and learning from them) is how we gain in intel

In physics, cold is the absence of heat. Not so in biology, says Ed Yong in Immense World : “(Cold) is a different sense in its own right.” Animals use a variety of sensors, the most studied one so far are a class of proteins called TRP channels. They are found throughout the body on the surface. Some are tuned to hot temperatures, others to cold temperatures. The trigger for these TRP channels isn’t only temperature – certain chemicals can trigger them too. This is why chillis “burn” and mints “cool”.   When we think of extremophiles (creatures that live in extreme conditions), we focus on the adaptations they have to survive like heat-reflecting hair or anti-freeze in their blood. “But such adaptations would be useless if an animal’s sensory system were constantly screaming at it, triggering feelings of pain.” Extremophiles tweak their senses “to like it”. Even in case of humans, one TRP genetic adaptation is common amongst people living at high altitudes – does it give

We hear a lot of news on China’s economic growth slowing down, and what that could mean for China. I always take such news with a pinch of salt because it usually comes from the West (not exactly an unbiased source for such analysis). Which is why I was more receptive to Amit Kumar’s view . As Indians, we aren’t thrilled about China’s rise, but that doesn’t blind us to China’s achievements and prospects either.   If the world’s second largest economy at $18 trillion grows at 5.2%, is that really a catastrophic slowdown, asks Kumar. Isn’t it still a rate of growth that much smaller economies like UK, France, Germany and Japan would kill for? Kumar then proceeds to analyze the situation.   First, yes, the growth rate for such a large economy is impressive even at 5.2%. But with its huge population, that still means China’s per-capita is $12,000, making it a middle income country, not a high income one. A slowdown in growth should be a matter of concern for China – what if they ar

Ed Yong has this to say in Immense World : “Pain is the unwanted sense. It is the only one whose absence (in some organisms) feels like a superpower.”   How does the experience of pain occur? This may seem like a stupid question, but its answer leads to many things. The experience of pain depends on a class of neurons called nociceptors. The naked tips of these neurons pervade our skin and other organs. They are loaded with sensors that detect harmful stimuli – heat, cold, pressure, acid, toxin, injury and inflammation.   Nociceptors can be partially disabled. In mole rats, for example, the nociceptors are blocked wrt detecting acid. Why? Because they sleep in large groups huddled with each other. The ones that at the bottom would experience high levels of carbon dioxide. High CO2 levels in turn makes the blood acidic. If a mole rat reacted to acidity levels the way we do, it “would probably lead to an agonized sleep”. Hence, the nociceptors in mole rats are disabled wrt aci

As Donald Trump seems sure to emerge as the opposition candidate in the US, Janan Ganesh writes about the fears associated with populists. (The term “populist” refers to a politician who appeals to ordinary people who feel that their concerns are disregarded by established elite groups)   But many populists have risen across democracies worldover, and the associated fears of “democratic backsliding, liberal retreat and the assorted impact on global economy” have been heard for a long time. Now that we’ve seen enough of them in power now, says Ganesh, shouldn’t we look at the data on how countries have fared under populists, instead of just theorizing over what can happen?   Other than the one guy in Turkey, Erdogan, none of the other countries have done badly under populists. America under Trump, Italy under Meloni, Israel   under Netanyahu… none of them did badly economically: “This is the liberal nightmare: not that populists abolish democracy to remain in power, but that

Color vision doesn’t come from just the ability to detect different wavelengths, writes Ed Yong in Immense World . “It is about comparing them.” The signals from the three types of cones (Red, Green, Blue aka RGB) are added and subtracted by a complex of neurons. This “arithmetic” is called oppomency and is the basis of all color vision. Since different animals do the arithmetic differently, their sensation of color varies.   Remember those super-colorful fish from movies like Finding Nemo ? Why on earth are they so colorful? Wouldn’t they be conspicuous to their predators? Aha, while it may be uber-conspicuous to us humans, they are perfectly camouflaged wrt their predators. Remember, the sensation of color is subjective.   Scientists often use this subjectivity of color perception in two fascinating ways. Say, Species 1 preys on Species 2. The colors of Species 2 would probably be colors that Species 1 cannot see. Or if Species 3 wants to attract Species 4 (e.g. flowers

We are used to farmer protests in India. What are the reasons for the same across Europe, from France and Germany to Poland, wondered Pranay Kotasthane.   There are two immediate causes for it. First, the Ukraine war. When the war started, the EU removed the ban on agricultural imports from Ukraine. To help Ukraine. But that created a side-effect. Ukraine is so much more efficient and productive at agriculture than the EU that this move has hurt EU farmers. EU farmers are also worried that the ongoing trade negotiations with South America will further increase the import of cheaper agricultural products.   Second, the EU has changed several policies to reduce the effects of climate change. This includes measures like “reducing pesticide use, developing organic farming, protecting biodiversity, and sunsetting fossil fuel subsidies in agriculture”. All these moves hurt farming and farmers.   The specific cause for protests in different European countries are different, but a

How does sight work? Every animal’s eye has light-detecting cells called photoreceptors, explains Ed Yong in Immense World . While photoreceptors vary, they all share a universal feature: they contain proteins called opsins. Opsins tightly embrace a partner molecule called a chromophore. The chromophore absorbs the energy from light and instantly changes shape. Its contortion forces the opsin partner to reshape itself, setting off a chemical chain reaction that ends with an electrical signal travelling down a neuron.   And yet, there are so many different ways of seeing: “Animal eyes can be bifocal or asymmetric. They can have lenses made of protein or rock. They can appear on mouths, arms, and armor.”   This seems like a paradox: “If all vision relies on the same proteins, and if those proteins all detect light, then why are eyes so diverse?” The answer? Because light can provide a diverse set of information – it can hint at temperature, time of day, or depth of water.

In the ongoing border disputes with China, we obviously see them as the aggressor. China obviously feels it is justified, so I am not interested in their reason, real or imagined. But have been curious as to how China views India on the border disputes.   I found Bharat Sharma and Anushka Saxena’s take on the topic based on Chinese articles quite informative. Not surprisingly, the Chinese feel India is trying to negotiate a border that is strategically to India’s advantage. Second, they believe/ fear/ suspect that India is in a “non-treaty alliance” with the US , and therefore they feel that India tries to pressurize China to make concessions on the border with the implied threat, “Otherwise India may have to pull in America”.   A corollary of the Chinese suspicion that India is in a “non-treaty alliance” with the US is that the Chinese view every aspect of the border dispute with India via the prism of an additional concern – will a concession to India help America?   Lik

In Immense World , Ed Yong points out that smell seems to be the one universal sense among almost all species – every living thing can detect some chemicals. That makes sense (pun intended) when you think a bit. After all: “(Chemicals have been there forever and thus) are the most ancient and universal source of sensory information.”   A famous subcategory under the heading of smells is “pheromones”: “It refers to chemical signals that carry messages between members of the same species.” Think of them as smells that convey “standardized messages” – their use and meaning does not vary between individuals of the same species.   The famous ant pheromones are of three types: (1) Lightweight chemicals that rise easily into the air are used to “rapidly summon mobs” or to sound the alarm. (2) Medium weight chemicals that don’t disperse so quickly are used to mark trails; and (3) Heavyweight chemicals (so heavy they don’t even leave the body) are used as markers to help ident

Ed Yong’s wonderful book, Immense World , looks into how different living things perceive the world. We depend so heavily on vision, but others rely more on other senses. Bats relying on sound is the most well-known example, but as Yong explains, the list of other senses is, well, immense, and fascinating.   Yong explains the term “Umwelt” in this context – it’s a German word coined in 1909 that refers to what an animal perceives as the world around it. That depends on which senses it uses, the “resolution level” of those senses, and finally how the brain processes the signals. Put them in the same room, and the Umwelt of the human and the bat would be very different. “Each species is constrained in some ways and liberated in others… This is a book not about superiority but about diversity.”   He then asks us to consider the miracle that animals, including us, can perceive anything at all. Huh? “Light is just electromagnetic radiation. Sound is just waves of pressure. Smel

In Wanderers, Kings and Merchants , Peggy Mohan explains how and why English became the dominant and preferred language of education in India. Contrary to popular belief, it is not a legacy of the British! How does she come to that conclusion? Even Macaulay, she points out, called for primary education to be in the local language, and suggested the switch to English only for secondary education. And even then, that switch was totally voluntary.   Post-independence, she says, it was many Indians who pushed for English for different reasons. BR Ambedkar, for example, supported English since he feared Hindi, esp. the Sankritized version, would be a disadvantage for the lower castes and an advantage for the (northern) Brahmins. South Indians feared the same – making Hindi the preferred medium of language would confer an unfair advantage to the north.   While some wanted to phase English out and replace it with either one or multiple Indian languages, they agreed that such a move c