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Birds can see Earth's magnetic fields because of cryptochromes in their eyes
- iaw 9y agoFlagging for a title change, perhaps: "Birds can see Earth's magnetic fields due to protein in their eyes" or the original, more clickbait-y title: "Birds Can See Earth's Magnetic Fields, And We Finally Know How That's Possible"
- dang 9y agoSeems to me the first part of the title makes a reasonable whole title, so let's go with that for now. Also, we changed the URL from http://archive.is/SlcSL http://archive.is/SlcSL. archive.is is an excellent site for archiving, but not for HN submitting, because it's important for readers to see the actual domain. For the same reason, we don't allow link shorteners.
- stan_rogers 9y agoThe eye link to magnetic field navigation has been known for years; the mechanism has not been.
- dang 9y agoOk, we've put some cryptochromes in the title.
- lurquer 9y agoIs there practical expirementsl evidence demonstrating birds can sense magnetic fields? That is, can you train a bird to select between two boxes, one of which contains a strong magnet? Just wondering. I'd read about theories regarding iron in the beaks and whatnot. Sounds cruel, but why not (a) train the bird to select the magnet, then (b) remove beak and check if it can still do the trick, or (c) remove eyes and see if it can still do the trick. I'm not entirely sure, though, that (a) has been accomplished. Can't find anything on it.
- piptastic 9y agomaybe just blindfold the bird, instead of removing the eyes
- godelmachine 9y agoYou are genius, coz I consider myself non violent, and even I couldn't think of the blindfold idea when the above guy spoke of removing their eyes
- lurquer 9y agoI considered blindfolding, but from what I gather the protein would be activated merely with the presence of the field. Looks like the humane way to test, according to the article cited above, is to affix magnets to the eyes/beak to see if it disrupts anything. In any case, in retrospect, I personally feel my suggestion to remove the beak is more cruel than removing the eyes. Both are hideous to contemplate. But, a bird without a beak? That's just a miserable thing to imagine.
- caf 9y agoThe original article suggests that the cryptochrome responsible for magnetic sensing must be stimulated by light to work, and in particular light of the right wavelength.
- jrimbault 9y agoDon't most bird just go to sleep when blindfolded ? Or is it just an idea that got in my mind ?
- elchief 9y agoAlligators do. Not sure about birds
- SAI_Peregrinus 9y agoThey don't tend to actually sleep. They do become more docile, because they can't see to fly without risking hitting something.
- jasonkostempski 9y agoI've heard people can too if they look at the sky under the right conditions.
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- tangent128 9y agohttps://en.wikipedia.org/wiki/Haidinger%27s_brush https://en.wikipedia.org/wiki/Haidinger%27s_brush is a real and really cool phenomenon, but it detects light polarization, not magnetic orientation.
- jasonkostempski 9y agoDoes the polarization of the light in sky correspond with the poles of the earth? If so, since the effect has direction, wouldnt you have a compass in the sky? I was just able to see the effect for the first time using this image [1] full screen on my phone :) Brightness up, screen rotation off, hold out the phone and turn it like your steering a car. Jumped right out at me. It's always at the center of my vision, so if I look around the screen as I'm turning, it follows. The yellow always points to the longer edges of my phone. It's hard to hold it in view when not turning though. [1] http://www.solidbackgrounds.com/images/2560x1600/2560x1600-vivid-sky-blue-solid-color-background.jpg http://www.solidbackgrounds.com/images/2560x1600/2560x1600-v...
- jasonkostempski 9y agoLooks like the polarization in the sky coresponds to the sun, not the poles. https://mysite.du.edu/~jcalvert/optics/haiding.htm https://mysite.du.edu/~jcalvert/optics/haiding.htm
- tahw 9y agoCan anyone explain in layperson terms how this is different from regular old polarization?
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- iaw 9y agoLight travels from one point to another in a direction. Perpendicular to that direction light "wiggles" on it's way from origin to destination. The direction of the 'wiggle' is the polarization of the light. Unpolarized light wiggles in every direction while polarized light only wiggles in one. Certain things (like how the sun shines on the sky) creates polarized light naturally. The earth's magnetic field DOES NOT polarize light. Birds have a protein in their eyes that uses blue light + the earths magnetic field to visualize the magnetic field around them. Similar to visualizing the polarity of light, we lack the ability to visualize magnetic fields, making both foreign concepts.
- tzs 9y agoAre you referring to animals (including, under the right conditions, humans) seeing the polarization of light? That allows them to figure out the position of the Sun when it is not visible due to clouds, which is indeed useful for navigating. But what this article is about is seeing the Earth's magnetic field. At least some migratory birds are able to detect both their longitude and latitude [1] [2], which requires more than just knowing where the Sun is. Humans have been able to figure out latitude for a very long time...at least as far back as the ancient Greeks, and probably much farther back. Longitude, on the other hand, eluded us until we were able to make reasonably accurate clocks. For sea navigation, that wasn't until the 18th century, long after we had compasses and knew about polarized light. [1] http://www.cell.com/current-biology/abstract/S0960-9822(17)30882-5 http://www.cell.com/current-biology/abstract/S0960-9822(17)3... [2] https://www.uni-oldenburg.de/en/news-single/art/how-migratory-birds-solve-the-longitude-problem-3136/ https://www.uni-oldenburg.de/en/news-single/art/how-migrator...
- neom 9y agoSo couple this with evolution and you have migration, no?
- mywittyname 9y agoProbably migration existed first, but those with the ability to see the magnetic field were much more successful at migrating, probably due to expending less energy during.
- gcb0 9y agotitle was not click bait. they can actually see it. nice. can't wait for the bodymod crowd to catch up on that one
- pkghost 9y agothe mechanism has to do with chromatin and quantum entanglement in the bands that connect the rods (cones?) in their retinas. don't think the bodymod crew is going to catch up to this any time soon... AR will get there first for sure.
- piracykills 9y agoThey've already managed to use CRISPR to give color blind primates their full vision back... http://www.neitzvision.com/research/gene-therapy/ http://www.neitzvision.com/research/gene-therapy/
- Terr_ 9y agoReminds me of some filler-dialogue from the game Deus Ex (2000), where a late-working employee in the building you need to infiltrate is complaining: > This chemoreceptor patent-proposal is kicking my ass. Hundley won't let me down until it's done. Hardly worth filing for, in my opinion. Who wants to smell the difference between xenon and radon?
- John_KZ 9y agoIf the cryptocrome mechanism is real, that's pretty spectacular. I thought that the idea of magnetoreception was mostly abandoned in favor of visual navigation, but I was wrong.
- askafriend 9y agoIs it bad that I first thought of the electric scooter company Bird?
- tzs 9y agoI wonder if they would perceive unnatural magnetic fields, particularly small, strong fields as something strange enough to avoid? If so, I wonder if one could discourage birds from hitting windows by arranging for a strong magnetic field outside the window? There are ways to discourage birds from flying into windows, but they often make the window less useful to humans.
- mdesq 9y agoOr keep them away from airports.
- pjmlp 9y agoEagles are very good avoiding planes and working as airport security buddies.
- aylons 9y agoWell, maybe some do, but surely not all. Transmission lines do have some strong magnetic fields around them and birds don't seem to care much.
- rcthompson 9y agoThere have been experiments showing that attaching magnets to birds' beaks inferfere's with their ability to sense magnetic north. So yes, they can "perceive" any magnetic field, but since their main use for magnetic fields is finding north, any other field is likely going to confuse and disorient them (similar to how artificial lights confuse moths that mistake them for moonlight), making them more likely to crash into objects, not less.
- fmntf 9y agoIf you liked this story, I recommend you "Life on the Edge: The Coming of Age of Quantum Biology". https://www.amazon.com/Life-Edge-Coming-Quantum-Biology/dp/0307986829 https://www.amazon.com/Life-Edge-Coming-Quantum-Biology/dp/0...
- everyone 9y agoI wonder if the Earths magnetic field flipping every half a Million years affects birds untowardly? Or have they evolved to deal with it?
- justinhj 9y agoA totally uneducated guess is that they will automatically handle the transition. In experiments with humans wearing glasses to vertically flip their visuals they start to see the flipped view as normal after a few days. No doubt birds would be the same. There’s also the evidence that birds have not gone extinct
- webbles 9y agoI think it would be hard to evolve to protect against something that only happens every half million years. We're probably going to need to observe the behavioral changes the next time it happens to have any clue.
- throwaway2048 9y agolots of subpopulations of many migratory birds dont infact migrate, or migrate very short distances. May play a role in their recovery.
- doomjunky 9y agoI'm not an expert in this domain, but my guess is that a flip of the eaths magnetic field is not instantaneous, but it takes over a few bird generations.
- gilgoomesh 9y agoIf the images in the article are accurate, the birds don't really see the polarity of the field, merely the alignment, so they don't really see "north", "east", "south" and "west", merely "latitudinal" or "longitudinal". They would probably combine with sunlight to get the real orientation – an approach which would continue to work with a flipped magnetic field.
- andai 9y ago
- volkk 9y agoSlightly off topic, but I am so thankful for firefox's reader. The amount of annoying ads blinking/flashing is enough to drive me up a wall
- abrowne 9y agoYou should try Firefox's tracking protection. This was actually one page I didn't use reader view for!
- JumpCrisscross 9y agoCould someone please explain the physics in respect of how blue light and magnetic fields measurably interact with this protein?
- CitizenKane 9y agoIt's actually linked in the article, this explains more about the working theory they have https://physicsworld.com/a/birds-measure-magnetic-fields-using-long-lived-quantum-coherence/ https://physicsworld.com/a/birds-measure-magnetic-fields-usi...
- notaspider 9y agoBirds are so cool!
- ChuckMcM 9y agoThis raises some interesting questions for me. First since I've been doing some Software radio stuff of late, I'm wondering if there is a way to build a chemical detector for magnetic fields that would allow one to pick up signals without a giant magnetic loop antenna. The paper (linked in another comment) suggests that the frequency response is low (1uS to 100uS) so it would not be a high bandwidth link :-). The other is what happens when the poles swap?[1] Do the birds commit mass suicide as they fly north for the winter and south for the summer? [1] https://www.extremetech.com/extreme/192522-earths-magnetic-field-could-flip-within-our-lifetime-but-dont-worry-we-should-be-ok https://www.extremetech.com/extreme/192522-earths-magnetic-f...
- basementcat 9y agoGeomagnetic reversal is not some atomic event but a gradual process lasting for several kY. Different parts of the Earth are in different stages of of the reversal, some further along than others. https://en.wikipedia.org/wiki/South_Atlantic_Anomaly https://en.wikipedia.org/wiki/South_Atlantic_Anomaly
- ChuckMcM 9y ago"Atomic" no, but there is evidence it isn't kY either. The article I linked was one of many that discussed the implications of the paper "Extremely rapid directional change during Matuyama-Brunhes geomagnetic polarity reversal" [1] published in 2014. In that paper, the authors studied different Lava flows that suggested a reversal can happen in a single human lifetime, with a change as rapid as 6 degrees per day. I believe that a polarity change in fewer than 100 generations would be challenging for most species that see or use the magnetic field to adapt. [1] https://academic.oup.com/gji/article/199/2/1110/618671 https://academic.oup.com/gji/article/199/2/1110/618671
- selimthegrim 9y agoI think the nitrogen-vacancy center in diamond might fit your bill.
- pknopf 9y agoI'm not sure why, but the few times in high-school that I took acid, I could see lines in the night sky going north to south. It was deterministic, like clock work. Does anybody have an ideas why? I mean, I wasn't really hallucinating, I didn't take too much. I could always truely find north or south. I couldn't tell what was north or south, but I could draw the line, always. Am I crazy? I mean, I'm not saying I'm a bird, but...
- caf 9y agoEven if you could see magnetic fields, it wouldn't look like lines in the sky running north to south, so this does sound like an hallucination.
- pknopf 9y agoHow do you explain that they were always from north-to-south? I mean, I tried hard to trick myself even. An actual hallucination couldn't know.
- caf 9y agoI don't think I have to explain (though the first explanation that comes to mind is that you were familiar enough with the location to have a pretty good idea of approximately which direction you were facing). The point is that magnetic field lines are a convenient diagrammatic tool, but don't have a direct correspondence to any physical reality. It's just like the way we sometimes draw electromagnetic radiation as a sine wave, but try as you might you won't ever observe little squiggly sine waves in physical reality.
- snissn 9y ago> The point is that magnetic field lines are a convenient diagrammatic tool, but don't have a direct correspondence to any physical reality. Magnetic field lines correspond as much to physical reality as anything possibly can. https://physics.stackexchange.com/a/80913 https://physics.stackexchange.com/a/80913 Also here's a trippy video: https://www.youtube.com/watch?v=rUZsojDdEbE https://www.youtube.com/watch?v=rUZsojDdEbE
- hyperpallium 9y agoWhat is it like to see a magneric field? Because it's in their eyes, it would have a visual interpretation. And some evolutionary advantage to that visual advantage, else the cells could be anywhere (unless there's a biochemical similarity to cones?) However, a field isn't like photons hitting the retina. It would probably be a new colour, which we can't imagine, but I'm asking where that colour would appear, to indicate the field. Perhaps a faint fog, varying in strength with direction - like the sky at dusk and dawn.
- caf 9y agoThere are some speculative illustrations at the bottom of the article.
- phasnox 9y agoCryptoc.. what? Crypto?! Sir when ICO?
- andai 9y agoIf you have 3D polarized glasses from the cinema you can go outside on a sunny day see this alignment in the sky. It's really cool, highly recommended
- caf 9y agoThat's not a magnetic field, that's polarisation of the light in the sky due to scattering.
- rs86 9y agoCrypto birds? I'm in
- eganist 9y agogrep "power line" ...am I really the only one who thought about whether this might contribute to why power lines are so attractive for birds to perch on?
- dschuetz 9y agoIt's likely that they might see the power lines' magnetic "signature" before everything else, as if the lines are highlighted or marked by a visual filter. Large congregations of birds on power lines preparing for a flight, however, is not a clear indicator for that. Perhaps power lines are just more convenient than searching for a tree large enough for the whole flock.
- pjpor 9y agoI suspect the magnetic field around a power line is thousands of times more powerful than earth's magnetic field. It would likely overload the birds senses and not be a pleasant experience.
- jakubp 9y agoTheir perception could be non linear, much like our perception of light intensity. Or it might be adjusted automatically to a higher value, dimming the earth's field but making power lines "bright" but not blinding. What a cool possibility overall!
- goalieca 9y agoThere’s a difference with power lines because it runs an AC current. The earths magnetic field is static for all intents and purposes.
- gmiller123456 9y agoI'd think a more plausible explanation would be that birds prefer a location difficult for predators to reach undetected, and which has a wide field of view. I think it's also presumptuous to assume that just because an organism can see something better, means they prefer it. E.g. There's no doubt that humans can see bright flashing multi-colored lights better than sunlight on an overcast day, but I don't think anyone would argue that humans would prefer the blinking lights over the natural ones.
- smrtinsert 9y agoI would love to add this ability.
- unit91 9y ago> Whoa, evolution. Just... whoa. At some point this really starts to sound ridiculous.
- tzahola 9y agoCryptochromes? Will there be an ICO?
- digitalshankar 9y agoCryptochromes? That sounds like Google launched a cryptocurrency. These birds are mining Cryptocurrency using Magnetic fields. LOL!
- ada1981 9y agoIf birds can figure out how to have blockchain based browsers embedded in their eyes to help with navigation, why can't we just copy that tech for our own uses? Can we do an Initial Cryptochrome Offering?
- jugg1es 9y agoThis is really hard to understand in terms of how the eye works. Conventional sight works by detecting photons hitting the retina. But "seeing" a magnetic field seems like it would only work when the eye is literally inside of the field. Magnetic fields don't project or reflect off of things, they are where they are. The eye would have to be directly affected by the field to see it. And then they wouldnt be able to see parts of the field they are not currently in. Magnetic fields don't radiate anything, they ARE the radiation. It's like trying to see a laser that is not pointed at your eye. It's there, but it cant be detected because no photons from it are hitting your eye.
- mygo 9y agoyou can see a laser that is not pointed at your eyes. Use fog. The atmosphere is known to diffuse the vectors of electromagnetic radiation. That’s how we get blue skies and red sunsets. Who says it’s not having the same effect on earth’s magnetic fields
- jugg1es 9y agoYou are kind of proving my point though. With fog, you can see the laser because photons are bouncing off the fog and hitting your eye. This article isn't saying that photons are bouncing the magnetic fields and then hitting their eyes, they are saying the eyes can literally detect magnetic fields. If the birds were seeing magnetic fields via how they interact with photons, then everyone would be able to 'see' magnetic fields because we can all see photons. This is saying that the magnetic fields are directly visible by birds.
- mygo 9y agoI’m aware that photons have to physically interface with the retina to be seen. You’re missing my point. Earth’s atmosphere acts like the fog as a laser travels through it — it diffuses the vectors, making them visible to an observer not along the path from the light source. When you look up at the clear sky during the day you don’t see the sun and then pure black space (and stars). Likewise the effects of the magnetic field interface with earth’s atmosphere. For example Earth's magnetic field deflects solar wind. The solar wind interacting with the magnetic field transfers some of its energy into earth’s atmosphere.