I stumbled upon my story about a trip to Azerbaijan 15 years ago hosted by Anton Kamolov and Oli Shelest. The funniest part is that I don’t even remember it being there, listening now as if it’s the first time.
P.S. Facebook doesn’t make previews because the domain scares Facebook. Well, Facebook scares the domain too.
I am reading Ed Yong’s “An Immense World” about how animals perceive the world. It feels like this is the fifth or sixth post on the topic. Currently, a very intriguing chapter about magnetoreception. The dull parts remain off-stage, I only share the most roof-shattering discoveries on the topic with you. Not always from “recent years,” but we didn’t cover biology very thoroughly in school.
Generally, everyone knows about pigeons that manage to arrive exactly where needed from any point. Interestingly, as of today, no one understands the physics and biology of this phenomenon definitively. There are three theories, which I’ll discuss later.
It turned out that quite a lot of animals, not just birds, can navigate by Earth’s magnetic fields. Even humans have cells potentially telling the brain what’s needed, but evolution, with our speeds and the distances we travel, deemed it unnecessary. But whales, turtles, all sorts of flying creatures, even mice, and foxes demonstrate it quite well.
Recall that only in 2014 did one of the Ig Nobel prizes go to Czech researchers who demonstrated that dogs prefer to defecate aligning themselves along geomagnetic field lines, from north to south. My observations don’t confirm this, so I don’t have a prize, but they do.
Testing on birds was the easiest because they are small and the phenomenon there is easily reproducible. It turned out that birds have a predictable moment, having a German name Zugunruhe, “migratory restlessness.” As the time approaches, they start going crazy and fly wherever they must go. It’s not a signal from the heavens, of course, but something like that. And at such moments, scientists come and start wrapping birds in magnetic coils (Hermholtz coils) and noting in which direction the legs left more traces (Merkel & Wiltschko).
But with whales, it doesn’t work like that. However, whales leave clear signs—carcasses on the shore. In English, this is called “to beach themselves.” So, it turned out after 33 years of observations (Granger/Walkowicz), that these self-killings happen during the peaks of solar storms. Although this doesn’t prove that whales have a compass, there is a sense in which forces generated by the planetary layer of molten metal collide with forces unleashed by the fiery star, jointly influencing the minds of wandering animals, and determining whether they find their path or lose it forever.
Something else turned out interesting about turtles. It’s known that sea turtles crawl up on the shore to lay eggs, far enough from the water, but so that the newborns still have a chance to make it to the ocean. And these little ones, once born, quickly figure out which direction to run. And they run not just towards the water—at least because they simply don’t see it at first. By the way, this run is quite dangerous, as predators know the spot well (it’s the same one every time), and estimates suggest that one in 10,000 turtles survives. Specifically, Florida ones head for the North Atlantic Gyre—a formation in the ocean spanning several million square kilometers, swirling clockwise. On this planetary-scale carousel, they ride for 5-10 years and grow into adults. And guess where they lay their eggs? In the same place! That is, after 5-10 years of wandering the vast ocean, they pretty well understand where their spot is, where they managed to survive at least once.
So, what was discovered (Lohmann, 1991)—the turtles have not just a compass. A compass alone would show the relative direction, but for what was described above, you need a full GPS. Well, they have one. Research has shown that their brains sense two parameters of the magnetic field— the inclination of magnetic lines and intensity. Overall, these two parameters are more or less enough to figure out “where I am.” For example, at the poles the inclination is 90 degrees, and at the equator – zero. Intensity is generally higher at the poles, lower at the equator, but there are also various anomalies in the Earth’s crust affecting it. In the end, turtles figured out how to use this, and experience has shown that even from a completely new place, they correctly determine where to crawl and then where to swim.
Meanwhile, over the last 83 million years, the Earth’s geomagnetic field has changed places 183 times. But the genetic programs, apparently, are adapted to this.
Since they don’t have maps of Earth in their heads, only rules on where to swim under various combinations of inclination and intensity, and because the magnetic field is very, very weak, turtles have to swim quite a long time not entirely in the right direction to figure out how to correct their course. But in the end, they arrive where they need to.
How these sensory organs work isn’t fully understood. There are three theories. They do not contradict each other, and most likely, all three are valid.
According to the first, sensitivity to the magnetic field may be provided by magnetite (Fe3O4)—a ferromagnet, meaning a substance in which the magnetic moments of atoms are ordered and persist in the absence of a significant magnetic field. Their direction depends on the polarity of such a field (if it exists). In 1970, bacteria were found containing crystals of magnetite. I don’t know why bacteria need the south, but this is definitely proven. Well, if such magnetite needles can be combined with sensory cells, it’d make a biological compass. But so far, such haven’t been found. There’s a noticeable amount of magnetite in the cerebellum and in the brainstem, but these are not receptors, and they are located deep in the tissue—whereas it would logically be best to place magnet-sensitive structures closer to the surface to increase the number of signals they can perceive. Regular domestic chickens have deposits of iron minerals in the dendrites at the top part of their beaks, enabling them to be capable of magnetoreception.
According to the second, the culprit is electromagnetic induction. This is closer to electroreception in sharks and rays—I wrote about this two days ago, take a look, it’s interesting. Essentially, it’s about the generation of induced electric signals in organisms moving in a magnetic field, signals that could potentially be read by cells. But this second theory doesn’t work anywhere except in water—induced electric fields are too weak for detection due to the lower conductivity of air compared to water.
The third theory is the most complex, but seemingly the main one. Here comes into play quantum physics (skip if scary). It involves the assumption that the geomagnetic field can influence biochemical reactions inside the retinal receptor cell, similar to those that lead to the detection of light by visual pigments. Cryptochrome cells are responsible for detection. (Interestingly, these blue light-sensitive proteins have the prefix “crypto” from cryptogamic organisms—ferns, on which many studies of blue light were done, and cryptogamic organisms are called so in Russian—Taynobrachnie—because Carl Linnaeus didn’t find flowers—sexual organs, and the name then stuck.) So, the theory is that cryptochromes, influenced by light, can form pairs of radicals—molecules with unpaired electrons. These unpaired electrons are sensitive to magnetic fields, allowing cryptochromes to act as magnetic receptors. Changes in the magnetic field can affect chemical reactions within these radical pairs, which in turn can trigger signaling pathways in cells, informing the organism about the direction of the Earth’s magnetic field. Also, research has shown that birds’ visual cortex gets excited when this “GPS” is turned on. Apparently, they conditionally “see” the magnetic field overlaid on what they see in the visible spectrum—RGB+ultraviolet. Of course, looking through their eyes and brain will never be possible, but there are indirect signs that this is the case.
Well, in about a month it will be 4 years since I stopped going to the office at all. Time flies quickly
This farmer has a really cool and fun channel about everything related to food. Why broilers are GMOs, what they pump into the meat, etc. I once posted about this topic out of interest, and besides being informative and visual, it’s also quite amusing
Definitely watch the second part. The first is essentially an introduction. The second is really interesting. In the comments
Find ten differences
I am thoroughly enjoying Ed Yong’s book An Immense World, which explores how living creatures perceive the world. There’s a really interesting chapter on electroreception. I need this to better understand—it’s wildly interesting, and for you—I don’t know why you need it 🙂 but it’s really interesting, hit like if you agree it’s interesting.
Well, everyone probably knows about the electric eel, which with its electric organs can create a potential difference (voltage) of up to 860 V and a current strength of up to 40 mA—enough to lay down a horse. Literally, this was tested on horses in 1880 by Alexander von Humboldt, ending up with dead horses.
But the most interesting thing is not that they are just swimming batteries. It’s interesting that many animals have electroreception—they can sense their immediate surroundings just as a theremin does. Since electroreception requires a conductive environment, these are all aquatic creatures—catfish, mormyrids, notopterids and gymnotids. Specifically, the last group includes eels and knifefish. The Black Ghost or Knifefish—a popular aquarium fish—generates a small voltage, but not to kill, rather to “see” with its entire body and see through sand and objects.
This feature is called active electrolocation. Both weakly and strongly electric fish create around themselves a characteristic dipole electric field. If there are no objects in the water around the dipole, it is symmetrical. Its configuration depends on the water conductivity and distortions when an object with different conductivity from water enters the electric field. In other words, by using its electric field (generated by discharges) and electroreceptors, the fish feels disturbances in the field when something enters it. An electric potential redistribution occurs on the surface of the body, which helps them determine the direction of impact or “invasion,” the size of the object, etc. The black knifefish has 14000 electroreceptors distributed over its body. The organ of electroreception consists of specialized spinal nerves that are spontaneously activated and are the fastest firing cells known in the nervous system of any animal—they continuously produce electrical signals at a rate of more than 2000 times per second.
Considering that the speed of electromagnetic waves in water reaches 225,000 km/s, electroreception allows weakly and strongly electric fish to almost instantaneously react to field distortion (by fleeing or attacking), while signals from other sensory systems may be delayed in time. Unlike the ultrasound of bats, which I wrote about in the last post, here the electric fields do not move. Moreover, the fish can change the intensity of the electric field to enhance sensitivity and distance. Yes, it does take their energy, so they do it when necessary.
There were experiments when a knifefish distinguished a sealed opaque pot from another similar one by their contents.
It gets even more interesting. Since they can sense each other’s fields, they have adapted to use these fields for communication. Unlike everything else, radio communication is the most reliable, and here it’s essentially radio. The only problem is distance, but compared with the size of the fish, it’s still decent. Experiments show that electric fish are sensitive to changes in the field with a resolution of 1/1000000 second. They themselves emit signals with a resolution of about 1/2000 second.
Some species of fish can pulse their fields specifically for communication, and the shape of this pulsation—the duration and how the voltage changes over time—contains information about what kind of fish, sex, status, and sometimes identity. But timing—that is, a larger form determining rhythm, regularity, etc.—determines the essence of the message. There are “words” in this language that mean “let’s hurry,” and others about love.
For example, as I mentioned earlier, research by neurobiologist Ted Bullock has shown that the electrical field of the black knifefish pulses every 0.001 second, deviating by no more than 0.00000014 second. In other words, these are the most accurate biological clocks in the animal kingdom. If you attach a clock to the fish, it would be off by an hour per year. Moreover, the fish’s “radio” uses frequency modulation (FM) to transmit messages.
It turns out that electroreception is not only present in electric fish, but also in many others in the water. For example, sharks. They have special organs on their noses called the ampullae of Lorenzini. This allows them to capture electric fields and detect extremely small changes in their intensity. These organs got their name because in 1678, this doctor wrote “what the hell is on their noses,” and a biologist R.W.Murray answered him only 300 years later, but by then these things had already been named.
So, with these ampullae of Lorenzini organs, sharks and rays feel living beings, even if they are not visible—for example, when the prey is hiding in the sand. But how, sharks can’t generate a field, unlike the knifefish or eel? Therefore, this is called passive electroreception. All living beings generate microvoltages, and the shark’s organs feel this at a short distance. This discovery is already 50 years old, but for some reason they didn’t tell us such interesting things at school. For example, hammerhead sharks can detect an electric field of 1 nanovolt (1/1000000000 volt) per centimeter of water.
Among a large group of mammals, electroreception is known only in the Australian platypus and is suspected in the echidna. The platypus has 50000 receptors, and by the same principle as the shark, searches for food in murky water or on the bottom under sand. Besides everything else, its eyes, ears, and nose are closed under water, so it uses only electroreception. There was also an interesting experiment with bees. If you look at their world through organs of electroreception, there would be an entire universe. For example, flowers have a negative charge, bees—a positive (because they lose electrons in flight), and according to the experiment, bees can distinguish artificial flowers with different charges. Bees don’t have any ampullae of Lorenzini, but they do have sensitive hairs on their skin.
Sometimes you wonder how skillfully nature uses the laws of physics.
A very interesting description of the solution from Alexander Zhadan on how he searched for a wife using ChatGPT. He claims that he eventually proposed to a girl who, as stated, ChatGPT communicated on his behalf for a year. For this purpose, as reported, the neural network interacted with another 5200 girls, filtering out those deemed unnecessary and focused on one.
Alexander describes what’s under the hood of the system:
・GPT-4 API
・Google Chrome up to version 115
・Several hundred lines of Python with Selenium, Chrome Driver, FlutterFlow, LangChain, Torchvision
・Telegram API
・VPN
・Proxy
・Loads and loads of prompts
The prompt at the beginning of the acquaintance: You write that you liked the photos of a girl you are meeting. The acquaintance occurs in my name [specify]. You maintain the dialogue, ask questions
How GPT-4, as an acquaintance, communicates upon request: you write politely and simply to a girl named [specify] to communicate in the role of [specify]. You are busy and won’t be able to talk soon, but you keep the dialogue minorly active. To the girl, you are an acquaintance who establishes the relationship at this level. Only you know this and always write your request considering it
The history of creation and jokes are detailed in the thread – link to the long thread X with diagrams, codes, block —
. I can’t judge how truthful it all is, but I’d hire the dude as an architect even if it’s 100% fiction. Technically, everything is feasible, but it requires a lot of work to do it alone
A minute of English. Today I learned what a Suicide Run is.
Nadya was talking about her coaching routine, and I discovered for myself that it’s an interval exercise where you have to run to a certain point, then return, then run to the next, farther point, and return again. And it turns out there is also a Russian Twist. This is an exercise for the oblique abdominal muscles, performed by sitting on the floor, leaning back and rotating the torso from side to side.
Recently, I came across an interesting expression in a book: “to face plant.” It means to smash your face into something.
There’s also an interesting phrase “throw someone under the bus.” This expression is often used in situations where one person puts another in a disadvantageous position or blames them for something, to improve their own situation or reputation.
I don’t get it, why isn’t parallel export working? I want to watch the new Master and Margarita.
Reading and getting stunned. Here’s an update to my previous post about bats. So, it is known that they hunt nocturnal moths and butterflies, what in Russian is called “moth”. And a moth, as we have all seen many times, like butterflies, has scales on its wings, making it so terry. By the way, the structure of these scales creates colors through interference and diffraction, the pigments of which are completely absent in the insect, like blue.
It turns out that these scales are not just there but serve as protection against bats. Firstly, they absorb ultrasonic waves and reflect back a small part, which partially hides the insect from the “radar”.
Moreover, half of the scale-winged creatures have ears, which detect the bat much earlier than it can “see” them with its radar. And they make a getaway sooner.
But there’s an even cooler tool in the tiger moth. It has a mechanism that jams the radar. Special hammers, which it uses to create ultrasonic disturbances and confuse the bat. Experiments were conducted playing recordings, and the bats “broke down”. Whereas the Luna Moth doesn’t have these hammers, nor does it have ears or even a mouth, but with its tail, they create an echo, which also confuses the bat. An experiment was conducted with a moth with a damaged tail – it was eaten instantly, while healthy ones manage to disturb the bat’s flight so they don’t get caught. It’s definitely the tail doing it, but the physics of it all remains a mystery.
Check out the first post if you haven’t already
Hi, I'm Rauf Aliev. 