Why you can't see infrared

[ApostateAbe]

Recently, I took a tour of a company that gets airborne hyperspectral images of both land surfaces and sea floors. "Hyperspectral" means that the images are like a photograph but they go beyond the wavelengths of visible light, to include the infrared. I was shown a very beautiful image on dual computer monitors of a coastal sea floor, where they simulated the removal of all of the water, and there was the coastal ocean floor with its sandy bottom, rocks, coral, canals--an amazing image I have never before seen.

The image was drawn with a grid of very many points, each point having its own waveform of light that contains both the visible wavelengths and the infrared wavelengths. I asked the engineer if I could see the same topographic image but this time in the infrared instead of visible light, and indeed he converted the image for me.

The image was a grayscale, white symbolizing high infrared reflectance and black symbolizing low infrared reflectance. Some of the land was white, but anywhere with plants was dark, because plants do not reflect much infrared. The engineer made the point that this is why infrared sensors are used for night vision--humans reflect it, but plants do not.

The ocean water was nothing but black, just an expanse of blackness. Visible light penetrates and reflects on the water (mostly as blue), but the infrared light is merely absorbed. The engineer said that it was a natural wonder that we can see the same spectrum that the ocean water reflects. I said, "It seems like an evolutionary thing."

I had in mind our aquatic ancestors. It would be absolutely useless for their eyes to sense infrared light. They would never get to see anything in the infrared color. It may be a stretch, but this may explain why we can't see in that range, even has land-walking meat-eating apes who would benefit from seeing infrared wavelength in order to hunt.

What if we could? What if our eyes could sense infrared and our brains could interpret that signal as part of the visible spectrum? We would have a whole extra color. We can not possibly imagine what this color would be, since color is purely a subjective thing and everybody experiences their entire lives with the same set of colors (or fewer), nor have we yet managed to engineer our brains to see anything else.

We would see everything much differently. We would have a perspective of directly stark contrast between plants and animals that we would all take for granted. Nobody would be able to hide so well in the woods. All of our art would be drastically different and much more lucid, with an extra color on the painter's palette.

But we can't have that. All because, I propose, our lungfish ancestors had no use in seeing the infrared.

 

[Cognisant]

We have three different types of cone cell that enable us to see the colour spectrum that we do, so in order to add another colour we would have to add another type of cell, the nature of which would almost certainly determine what the new colour looks like.

I'm guessing it would look something like red, but redder somehow

 

[dark]

Very interesting, this is coming from someone who finds biology boring, your statement seems logical, very interesting, by this logic, it would be almost impossible for any life form to develop infrared vision, atleast any life form develped from water. There wouldn't have been a biological use for the first organisms to grow eyes, hum, which means eyes where developed first under water, of course they have became better over time for some. What kind of change would have to happen for an organism to begin to gain that sight? Of course for it to continue they would have to breed. Infrared would probably be set as another primary colour, making four colours on the colour to make things with would add a entirely new dimension to our sight, which because we can't see the colour yet, we can not define it. But it exists!

 

[ApostateAbe]

We have three different types of cone cell that enable us to see the colour spectrum that we do, so in order to add another colour we would have to add another type of cell, the nature of which would almost certainly determine what the new colour looks like.

I'm guessing it would look something like red, but redder somehow

I didn't know about cone cell, and it seems to reinforce my proposition. In order for land-bound tetrapods to evolve the advantage of seeing infrared, they would need two somewhat complex evolutionary steps in both their eyes and their brains--in their eyes to develop that set of infrared-sensing cone cells, and in their brains to be able to process that extra information. Since our aquatic ancestors developed their complex system of vision for visible light, it would take too much extra engineering to go to the infrared spectrum after crossing onto land.

Like I said, you can not possibly imagine what a whole new color like infrared would look like.

 

[ApostateAbe]

Very interesting, this is coming from someone who finds biology boring, your statement seems logical, very interesting, by this logic, it would be almost impossible for any life form to develop infrared vision, atleast any life form develped from water. There wouldn't have been a biological use for the first organisms to grow eyes, hum, which means eyes where developed first under water, of course they have became better over time for some. What kind of change would have to happen for an organism to begin to gain that sight? Of course for it to continue they would have to breed. Infrared would probably be set as another primary colour, making four colours on the colour to make things with would add a entirely new dimension to our sight, which because we can't see the colour yet, we can not define it. But it exists!

I may go for a PhD in biology and make this my thesis. I thought for sure that someone else had would have already thought of this, but maybe not. The standard answer for why tetrapods cannot see infrared is that the radiation from the sun is mostly in the visible wavelengths. I find that explanation insufficient.

Like Cognisant said, you would need another set of cone cells in the eyes to sense an extra color like I have in mind, but it may be evolutionarily possible just to extend the sensing wavelength of the red-sensing cone cell, and I may look into that as a potential weakness of the proposition.

 

[Cognisant]

The brain is very adaptable, if you provide a new source of input it'll adapt to it with remarkable speed

http://en.wikipedia.org/wiki/Kevin_Warwick

By means of the implant, Warwick's nervous system was connected onto the internet in Columbia University, New York. From there he was able to control the robot arm in the University of Reading and to obtain feedback from sensors in the finger tips. He also successfully connected ultrasonic sensors on a baseball cap and experienced a form of extra sensory input.

 

[dark]

Don't think modifying a current colour cone would allow infrared to be seen since it will most likely be a new colour in every aspect. And why is it called infrared. The new colour would have to be infrared. Wait a sec, isn't radio waves sent also on the same scale, but they don't transfer sound, but information that we decode from a machine into sound. Could we also be capable of somehow seeing that or is that just impossible? I know in my biology book it shows, not sure of the order, Ultra-Violet, Visable Light, Radio Waves, Infrared. If these are all forms of light wave lengths would it be possible for more advanced evolutionary forms to be capable of seeing them all? My biggest question is this, what was so important about visable light that our ancestors benefited from it. I know the importance of sight and all, that is not the point, what was happening to the earth at that moment of so much time that the fishie people of us needed the light vision more than any other senses they had or hadn't developed, and is it possible for us to develop another sense of the world around, in which we can understand things better.

 

[EyeSeeCold]

http://en.wikipedia.org/wiki/Tetrachromacy

 

[Agent Intellect]

Don't think modifying a current colour cone would allow infrared to be seen since it will most likely be a new colour in every aspect. And why is it called infrared. The new colour would have to be infrared. Wait a sec, isn't radio waves sent also on the same scale, but they don't transfer sound, but information that we decode from a machine into sound. Could we also be capable of somehow seeing that or is that just impossible? I know in my biology book it shows, not sure of the order, Ultra-Violet, Visable Light, Radio Waves, Infrared.

Infrared is a fairly large range of electromagnetic radiation - a bit larger than the visible light spectrum. It seems a bit vague to lump all of infrared into one category. It's wavelengths are longer than visible light, but shorter than microwaves and radio waves.

If these are all forms of light wave lengths would it be possible for more advanced evolutionary forms to be capable of seeing them all? My biggest question is this, what was so important about visable light that our ancestors benefited from it. I know the importance of sight and all, that is not the point, what was happening to the earth at that moment of so much time that the fishie people of us needed the light vision more than any other senses they had or hadn't developed, and is it possible for us to develop another sense of the world around, in which we can understand things better.

Visible light are wavelengths that both make it through our ozone layer without reflecting, and reflect off the surfaces of objects on earth. Light with wavelengths shorter than violet (ultraviolet) are highly reflected off the ozone layer and the surface of water. Our sea faring ancestors would have not been able to see anything in the ultraviolet range underwater. Infrared has a tendency to transmit through things (as is talked about in the OP) so would also not have been conducive for sight. The range of light that we see was the wavelengths that were easiest to pick up, and were therefore selected for by natural selection.

There are probably people who can see wavelengths slightly longer and/or slightly shorter than some other people. If this conferred some sort of survival advantage over other people, over time the ability to see slightly more ultraviolet or infrared would be selected for. As our range of vision increased, those people could have children that can see even further yet into the ultraviolet or infrared, and so on until several thousand generations, there would be a population of people who can see a fraction of the UV or IR spectrum.

 

[Kuu]

Recently, I took a tour of a company that gets airborne hyperspectral images of both land surfaces and sea floors. "Hyperspectral" means that the images are like a photograph but they go beyond the wavelengths of visible light, to include the infrared. I was shown a very beautiful image on dual computer monitors of a coastal sea floor, where they simulated the removal of all of the water, and there was the coastal ocean floor with its sandy bottom, rocks, coral, canals--an amazing image I have never before seen.

The image was drawn with a grid of very many points, each point having its own waveform of light that contains both the visible wavelengths and the infrared wavelengths. I asked the engineer if I could see the same topographic image but this time in the infrared instead of visible light, and indeed he converted the image for me.

The image was a grayscale, white symbolizing high infrared reflectance and black symbolizing low infrared reflectance. Some of the land was white, but anywhere with plants was dark, because plants do not reflect much infrared. The engineer made the point that this is why infrared sensors are used for night vision--humans reflect it, but plants do not.

whoaa I thought that it was because humans emit infrared light... like all warm bodies... and plants being cooler, don't emit as much... though it might be also the reflectivity.... (there are several different technologies...)

What if we could? What if our eyes could sense infrared and our brains could interpret that signal as part of the visible spectrum? We would have a whole extra color. We can not possibly imagine what this color would be, since color is purely a subjective thing and everybody experiences their entire lives with the same set of colors (or fewer), nor have we yet managed to engineer our brains to see anything else.

And one day we will! Neuroplasticity and transhumanism ftw!

We would see everything much differently. We would have a perspective of directly stark contrast between plants and animals that we would all take for granted. Nobody would be able to hide so well in the woods. All of our art would be drastically different and much more lucid, with an extra color on the painter's palette.

Wait a sec, isn't radio waves sent also on the same scale, but they don't transfer sound, but information that we decode from a machine into sound. Could we also be capable of somehow seeing that or is that just impossible? I know in my biology book it shows, not sure of the order, Ultra-Violet, Visable Light, Radio Waves, Infrared. If these are all forms of light wave lengths would it be possible for more advanced evolutionary forms to be capable of seeing them all?

Indeed. And much more things would be extremely different. Opaqueness / transparency of materials is dependent on wavelength... all of our objects and architecture and technology would be much more different if we could see different wavelengths... high-tech materials like the glass we use in buildings now is nearly 100% opaque to infrared... While certain fabrics are transparent to infrared light, so even clothes would be different materials... (you can test this if you have a DSLR and remove the IR filter from the sensor, and have voyeur tendencies)... If we could see the low ends of infrared, we could have thermal vision, and see all kinds of weird glows everywhere (living creatures and hot chemical processes for example)... where now we would see nothing, and our nights wouldn't be so dark... if we could see even lower frequencies, we'd be blinded by all the light everywhere, with radio, cellphones, wi-fi, satellite TV and so much other stuff...

I have wondered if we ever encounter an intelligent alien civilization, in which wavelengths would their eyes see, and their ears hear? and if they would be similar enough to us to appreciate our art and technology as we do... or if they would be so different that all our culture would seem, well, extremely alien and bizarre and incomprehensible to them... (and theirs to us)... and thus inter-cultural understanding nigh-impossible...

or if they would have technologies to sense a wide range of these and filter them selectively... so they could "see as we see"...

(While morphological differences would make most of our objects and environments awkward to them [as they are for very short/tall or disabled humans], it is sensorial capacities that take an essential role in cognition and provide the most insurmountable obstacle to understanding non-human perception and thought)

Alas these very amusing concepts are rarely touched upon in the crap popular science fiction of our times... but I eagerly await the time when I can augment my vision with all sorts of crazy stuff and create as-of-now incomprehensible transhuman art

 

[ApostateAbe]

Yes, Kuu, I was wrong about humans reflecting infrared. They emit infrared, and the mixup was on my end, sorry.

 

[EvilScientist Trainee]

I believe that most of organic reactions are favoured by being in aqueous solutions, that because water has a wide range of characteristcs that make it suitable for a decent solvent, such as its geometry favouring the hidrogen bonds. But then again, one could say that sulfur, that is just below oxygen in the periodic table, and some of these reactions can even be replicated in such solvent. The only response i have is that oxygen, due to its lower atomic mass, might be easier to form in space, thus being more common.

If my point holds any water (no pun intended), life if formed, would start on water. That would eventually lead to the inability to see infrared, as mentioned in the OP. However, it seems that infrared sensing isn't intrinsically associated to the eye. Aren't there those snakes who 'see' in infrared? In those animals, the infrared sensing is due to a membrane, where a chamber is filled with air, close to a group of thermosensitive receptors. The change in the heat sends information similar as those found in thermography.

Also, infrared is known to change the eletric dipole moment characteristics. Would infrared be able to induce isomerization in the cis-retinal?

So, i conclude (even thought i might be completely wrong), that infrared might not be really seen by the eye, and there would be the need to have another organ for that function.
But then, possibilities are infinite.

 

[dark]

Interesting, I know it is probably irrelevant, but since we sense light[visible] through the eyes, we sense sound through the ears, what wave lenghts are sound traveling on, I know it must be different from light since the speed difference. If all light wave lengths react differently, then as a post up above mentioned, we may need another organ to see something different than visible light. Or maybe not, and in reality I don't think we could actually test if another organism can sense the other wave lengths, since we can not detect them without equipment and our equipment can only give us information that we can see, which is in visible light.

 

[The Frood]

Sound waves have to have a medium to travel through, such as air, water or something. Same thing with other types of waves, they need a medium, and have no mass (I think).

Electromagnetic radiation (radio waves,infrared, visible light, UV, X-rays, and Gamma rays) is light (another weird thing, light acts like both a particle and a wave), and as such doesn't need a medium to exist, and it does have mass, that's why they can travel through the vacuum of space.

@Dark "since we can not detect them without equipment and our equipment can only give us information that we can see, which is in visible light"
We have equipment that measures information from the entire spectrum (excluding the extreme ends of radio and gamma radiation), haven't you listened to the radio? Or had an X-ray machine take a picture of your bones? Astronomy is a great example, we have pictures of celestial objects taken from all wave-types in the spectrum, ergo we have instruments that detect wavelengths other than visible light.

"in reality I don't think we could actually test if another organism can sense the other wave lengths, "
We can dissect said animals to see if they have "receptor" organs, we can experiment on said animals, put them in a pitch black room, and emit infrared or whatever (although UV and higher radiation isn't good for organisms...) stimuli and see if they react. There are ways to find out if they can detect other wavelengths.

For instance, as EST said, we know that some snakes can "see" infrared http://en.wikipedia.org/wiki/Infrared_sensing_in_snakes.
It incorporates a different organ, and a completely different chemical process than the eyes, we can see because of photochemical reactions, for infrared you would need heat sensitive.

Also, having two different sets of visual(ish) information simultaneously? where some things are opaque in one wavelength, and transparent or translucent in the other? I'm sure our brains could figure it out, but I still think that it would be screwy.

 

[EvilScientist Trainee]

I'd also like to remind that different wavelenghts display different energies. As wavelengths get smaller, their energy increase. Then, that energy may make electrons excitable on the outer orbitals -if strong enough- or not, if that energy isn't sufficient.

Then, the chemical mechanisms will have to be different. Visible light can cause isomerization, then igniting a signal to the brain. Infrared will be perceived as heat, and heat-sensitive proteins will ignite the signal. Larger wavelenghts might have no energy to promove any substantial change to ignite any signal, or if they promoted a change, that could be really slow to be efficient in a living being.

However, i'm not sure about UV sight. We can sense some near UV, that being the part of the UV that is almost immediately close to visible light. Maybe, if some organisms were created in a more UV rich environment, they could see further in UV. But i digress.

I can only wonder if differents parts of the eletromagnetic spectrum would need different organs to be sensed.

 

[dark]

Wow that is cool, never thought about putting animals in a dark room and submitting them to different wave lengths. Guess there are loop holes to everything haha. We don't need machines to decode data, we can just watch and see how other organisms react. So is this part of how animals seem to always know when danger is near, like in nature, but somehow never see that damn truck coming 75mph barreling down.

 

[orion]

think if we could see like some cameras do and see everything on the elctomagnetic spectrim. i believe we would see somewhat the same just picyyure it as though u strech the color spectrum across the rest of the spectrum we would see on so what we see as red would be more yellow and infrared would be what we see now as true red.

 

[James Black]

Given that (nearly?) everything emits IR, I would like to be able to see or "sense" it, but not through the same receptors (namely, our eyes) as we see the standard light spectrum. It seems like it may be too much clutter and simply get in the way of everything else that we see.

 

[Kuu]

Hm I found today this article commenting on scientific developments and the feasibility of expanding the range of our light sensing capacities: link

The thought that this is feasible in the extremely near future is tantalizing...

 

[kantor1003]

Cool! God knows how long it will take with the whole bureaucratic mess before one can finally do some modifications to man though.