Some Birds Can See Magnetic Fields 238
jamie found a post on the Not Exactly Rocket Science blog on research indicating that some birds can literally see magnetic fields, but only if the vision in their right eye is sharp (abstract at Current Biology). "The magnetic sense of birds was first discovered in robins in 1968, and its details have been teased out ever since. Years of careful research have told us that the ability depends on light and particularly on the right eye and the left half of the brain. The details still aren’t quite clear but, for now, the most likely explanation involves a molecule called cryptochrome. Cryptochrome is found in the light-sensitive cells of a bird’s retina and scientists think that it affects just how sensitive those cells are. ... The upshot is that magnetic fields put up a filter of light or dark patches over what a bird normally sees. These patches change as the bird turns and tilts its head, providing it with a visual compass made out of contrasting shades."
augmented reality (Score:5, Interesting)
augmented reality at its best.
Makes me think what other "natural augmented reality senses" are possible, or even already exist in other species.
Tech version? (Score:5, Interesting)
Silly, inferior mammals (Score:1, Interesting)
So, not only can birds see [wikipedia.org] a broader range of colours (they can see ultraviolet), a more detailed spectrum than we can (e.g., blue jays can tell the difference between "yellow" from a red-green mixture and "pure" yellow) thanks to having 4 or 5 types of colour-sensitive cells in their retinas (humans and other primates have 3), and having higher density of light-sensitive cells (=higher resolution), but they can also see magnetic fields?
I feel so cheated by evolution.
Re:Why haven't we evolved to see IR or microwave? (Score:4, Interesting)
Why would you need night vision if you are able to survive the day?
Animals with great night vision tend to have it because it is not safe for them to be out and about during the day when the majority of predators are up and about. Consequently a number of predators themselves developed night vision (they didn't develop it, just that predators with night vision were able to find a niche, see below). I'm assuming you mean to ask why humans didn't evolve the abilities, the answer is simple: we are well capable of being active throughout the day, and decide instead to rest at night.
Even though it is possible to push a human's visible spectrum into the IR range, with a long treatment of Vitamin A (http://www.edkeyes.org/blog/050825.html), there is no point in doing so, as it's not needed as a survival tool.
The same goes for microwave radio. We do not need it to be superior to all other animals on the planet, so there has never been a reason for why it would develop.
You have to remember that evolution is the process whereby an animal mutates randomly and a trait appears, if that animal survives to reproduce (not killed off by something) then that trait is passed on to a new generation. If that mutation proves negative to survival, chances are the animal dies and does not get to pass on that trait to next generation.
You can't simply expect a need for night vision to present itself, and in response the body evolves in order to comply with that need.
Re:augmented reality (Score:5, Interesting)
Electromagnetic radiation: everything from pretty longwave IR to UV is well documented(IR in certain snake's heat-sensor pits, UV in some insects, "visible light" is obvious enough) There are certain radiotrophic fungi [wikipedia.org], which can perform a process analogous to photosynthesis; but with gamma radiation. This isn't a directly sensory function; but it does imply that there is a biologically produce-able molecule, in the wild, that could serve as the basis of a gamma-ray vision system(if not, perhaps, a very fast one) The unknown(at least for me) is radio waves. I've never heard of anything using them; but organisms with conductive structures linked to their nervous systems are potential suspects....
Magnetic fields: Confirmed in birds and some insects; both as a 'compass-like' directional sense, and as a visual signal. And, since electricity and magnetism are related, anything with reasonably high-resolution magnetic sensors can detect electrical currents, as well.
Sound waves: Confirmed, obviously enough, across a pretty wide frequency band in all sorts of species, both as a conventional 'hearing' sense, and for detection and ranging.
Chemicals: Anything with a sense of smell is a pretty sensitive chemical detector, some better than others. Even bacteria can follow chemical gradients, and animals with sophisticated olfactory systems can detect tens or hundred of thousands of chemicals, and at fairly low concentrations...
Electrical currents: Sharks, possibly among others, can sense the electrical impulses that make your muscles move at distances long enough to make this a useful hunting tool. Don't know if anyone else has picked up this trick...
Can anyone think of other physical phenomena that may or may not have biological sensors capable of detecting it, and any known cases?
Re:Why haven't we evolved to see IR or microwave? (Score:5, Interesting)
Specifically, females with a 4th set of cones [post-gazette.com].
Spy vs Spy (Score:5, Interesting)
Some humans seem to be able to see a little further into UV, but nothing like chickens or certain insects.
In WWII the OSS recruited elderly volunteers with cataracts who could see into the UV range. They were posted as coast watchers for communication with submarines and landing parties.
One of the best reads around for the real world of spy tech is Stanley Lovell's Of Spies and Stratagems. Lovell was the OSS "Moriarty" - a later generation would see him "Q," and no less an enthusiastic, inventive and deadly prankster.
Re:augmented reality (Score:3, Interesting)
EM pollution (Score:2, Interesting)
OK, I should probably call Randi (Score:5, Interesting)
As a child, I found that if I were to walk under/near certain transformers, I started to see black waves at the very edge of my vision. I couldn't really describe it as they tended to be fairly quick, and explaining to somone just what waves of black at the edge of your vision would look like was/is difficult.
I grew up near a steel mill, and their furnaces were electric, and on a hill near where I lived there was this MASSIVE collection of electrical equipment (Transformers, relays, etc). If I were to walk along the outer perimiter of this area, I would see those waves again.
I've noticed this my entire life, and it happens rarely, but is always associated with electrical equipment. I also got the same 'waves' when I accidentally grabbed a makeshift fishing worm extractor (essentially an AC cord attached to a long metal rod you stick in the ground) I DEFINITELY saw the waves in my vision then (and nearly was electrocuted).
Now, is this something that other people have in the presence of very large em fields? Or did I stick a nail up my nose when I was a toddler and forgot about it?
It's not magic in any case, so I don't think I could go for Randi's offer right?
Oblig BSG (Score:1, Interesting)
I don't want to be human! I want to see gamma rays! I want to hear X-rays! And I want to - I want to smell dark matter! Do you see the absurdity of what I am? I can't even express these things properly because I have to - I have to conceptualize complex ideas in this stupid limiting spoken language! But I know I want to reach out with something other than these prehensile paws! And feel the wind of a supernova flowing over me! I'm a machine! And I can know much more! I can experience so much more. But I'm trapped in this absurd body! And why? Because my five creators thought that God wanted it that way!
Re:OK, I should probably call Randi (Score:4, Interesting)
So it does not surprise me at all to hear that some people can see E&M fields
I also don't want to come across as delusional, and I don't really see EM fields like a lot of people claim. It's just that when I was younger, and (confirmation bias maybe) in the presence of transformers. I saw a slight wavy blackness at the edge of my vision.
It's possible that more people get this all the time, and just don't notice it. It is very slight, and very transient. The transformer I walked past to check it out was also later determined to be malfunctioning (it began arcing electricity a year later).
It could be a completely benign aspect as well, and thus not really influenced by evolutionary pressures. I'm sure that until the 20th century, the chances of someone being exposed to a strong EM field were pretty low (Excepting thunderstorms perhaps), and since getting struck by lightning often has other warning signs (Like a giant ass thundercloud), being able to slightly see/feel the EM field isn't that advantageous.
For all I know, I could have just ingested too much iron as a kid and a strong field messes with something in my retina.
I don't even know if my vision is still good enough to produce the effect again. I think I am going to go take a walk past some places where I remember it happened and see if it occurs again. If it does, I'll definately contact Randi.
I'd have to think of some test conditions too. Maybe a bright room with no variation in the lighting or colors. Incandescent bulbs or sunlight would be nice for producing light with no extra EM fields. Some sort of wall housing the equipment to produce a field that I can't see. A computer randomly generating a control signal for the equipment. Maybe give me a dial that I can turn to indicate how strong the waves I'm seeing are.
Heh, as a test engineer, this could be fun.
Re:augmented reality (Score:3, Interesting)
A lot of scientists do philosophy, and a lot of modern philosophers are giant science junkies.
Then why does anyone teach logics where Leibniz's Law is true, given that it is false, has known to be false for over half a century, and this falsity has profound everyday consequences?
In the areas I'm interested in--identity theory, empiricist epistemology, ontology, and ethical choice under uncertainty--I am not aware of anyone working in the fields who has anything resembling a grasp of the relevant science done in the past half-century.
With regard to epistemological and ontological questions, for example, I've never read any philosopher who seems able to grasp that ontology can constrain concepts without determining them, whereas anyone with a modicum of scientific literacy has no difficulty at all with it. And if you talk to a philsopher about the ontology of actions (waves, for example) you'll rapidly find a level of innumeracy that's embarrassing. There are people out there who are willing to not just talk about but actually pronounce upon the ontology of classical waves without being able to solve the wave equation.
Go ask your favourite ontologist, "Can a wave be properly conceptualized as an action or a thing or both?" The answer will almost certainly stun you with its lack of understanding of the topic, unless you don't understand the topic yourself.
By "understanding science" I don't mean "read the blogs and pop sci garbage we see on /." I mean "actually have a working grasp of the topic", because that is what is required to do reasonable philosophy in an area.
Re:augmented reality (Score:3, Interesting)
Well, all scientists do philosophy. You might not agree with them, and they might insist that it is not philosophy, but that is a philosophy.
Back in my undergrad days, when I was majoring in philosophy, one of my friends was a physics/math dual major. We used to have rousing discussions about the philosophy of math and science, and she would always yell at me that philosophy had no role in these disciplines. I always told her, that the second she started actually discussing math and science as disciplines she was, in fact, being a philosopher.
The methodology of science is a philosophical device, and much of the processes of scientific discovery are within the realm of philosophy. Theory building especially. But the nuts and bolts of science are not. Finding that particle x decays into particle y isn't a philosophical exercise. Asking "how can we be sure", though, then the topic turns into one of epistemology.
Most of the recent books criticizing string theory are soundly philosophic, for example.
Can't see them, but have certainly felt them. (Score:3, Interesting)
I suspect having Iron in your body has something to do with it.
I was walking through a mall and was nearly knocked on my arse once by a weird field I entered. It felt a bit like bringing two magnets close together N to N. My girlfriend felt it too and we both reeled back a step and looked at each other.
Turns out, there was a giant old black and white TV screen from the seventies hanging overhead and displaying video from some security feed. It was cool, because we could walk in and out of the field and really feel it strongly each time. I was so intrigued that I wanted to call people over to check it out, but I was also feeling really woozy and the only people around were old ladies and other K Mart Shopper types who wouldn't have understood the significance.
I don't react that way most of the time, but I'd been meditating and doing lots of energy work that month. My perceptions were pretty raw and being in a mall was quite overwhelming. I ended up sitting outside to breathe it off. That's the downside to opening yourself up; the sickness of society can really burn you out. I think most people just have strong blocks in place so that they don't notice this stuff normally, like being around a bad smell for a long time makes it sort of fade in the perceptions.
-FL
Re:OK, I should probably call Randi (Score:3, Interesting)
Some people claim to be able to see people's 'auras'. Maybe they're also seeing E&M fields.
I bet we'd have more people with extra senses, if we hadn't burned them all a couple centuries ago. :P