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What Cats and Dogs Can See that Humans Can’t: You Won’t Believe it!

By Kerri Fivecoat-Campbell    February 25, 2014 at 03:10PM / (67) comments

Have you ever felt that your cat or dog can see something you don’t? Well, you may be right, according to a new study.


Cats, dogs, and other mammals are thought to see in ultraviolet light, which opens up a whole different world than the one we see, the study explains.


Seeing the World in Ultraviolet (UV) Light


UV light is the wave length beyond the visible light from red to violet that humans can see. Humans have a lens that blocks UV from reaching the retina. It was previously thought that most mammals have lenses similar to humans.


Scientists studied the lenses of dead mammals, including cats, dogs, monkeys, pandas, hedgehogs, and ferrets. By researching how much light passes through the lens to reach the retina, they concluded that some mammals previously thought not to be able to see UV actually can.


"Nobody ever thought these animals could see in ultraviolet, but in fact, they do," Ron Douglas, the study leader and a biologist at City University London, England, told LiveScience.


What purpose does being able to see UV light serve for animals such as reindeer, rodents, and other mammals? It allows reindeer to see polar bears, for example, which would be invisible in regular light because they blend in with the snow.


UV light also allows mammals to see urine trails. This would be helpful for prey animals, such as cats and dogs, to find food in the wild.



Originally appeared on Pet360.com


Image: INTVGene / Flickr



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Comments  67

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  • hmmmm...
    02/25/2014 06:51pm

    I've always wondered if my cats could see things I couldn't :)

  • 11/14/2014 06:50pm

    But it still doesn't explain what my cats "suddenly" see what's behind me!

  • 12/06/2014 05:19pm

    I've been learning about "ghost hunting" because I live in a haunted house, and from what I understand, some of the newer equipment they're now using scans the ultraviolet spectrum because they've found it can capture evidence they were previously unaware of. So this may very well explain what your pet is seeing when it stares behind you! Or maybe your pet is just hearing a bug lol.

  • 03/15/2015 12:34pm

    balaams donkey in the bible seen the angel, and Balaam never. The donkey tried to avoid walking on, because the angel was standing in the middle of the road. The donkey kept pulling away, and Balaam kept beating it. then the angel made himself known to Balaam, and wanted kill him for beating the donkey. but I wonder if that is why the donkey seen him, and the human never.

  • 07/26/2015 10:28am

    I've always loved the story of Balaam's donkey! Your clever theory makes perfect sense in light of this new discovery. I bet you are right!

  • 09/03/2015 10:39pm

    Thank you for the reply :)

  • 09/26/2015 08:53am

    SAW, NOT " seen." ASS, not " donkey."

  • 10/22/2015 11:26am

    Shut up you pompous ASS!

  • 10/22/2015 08:06pm

    Haha! He haw he haw

  • 09/26/2015 08:52am

    SAW, not " seen." ASS, not " donkey."

  • 09/26/2015 02:39pm

    Thank you! :)

  • 05/10/2015 01:17pm

    I bet your house is really scary! Have you ever seen a ghost in your house before?

  • 08/05/2015 05:30am

    I live in a house at the dead end of a 3 way crossroad. There is high entity traffic & my parrot can see entities. I can see them out of the corners of my eyes in the daylight. In the dark it is very easy to see an entity.

    There is only one entity that my parrot likes. When she pets her my bird just groans happily.

  • 08/18/2015 08:29pm

    There are ghost kitties in our apartment! I know at times our three cats see them. I on the other hand can only feel them brush by in an instant.

  • 09/17/2015 02:30pm

    My roommate can see them. Our recently departed Kitters came by twice that he saw.

  • 09/18/2015 02:28pm

    After my first cat was killed by a dog that entered our yard, he kept going to bed with me until I adopted my current cat. It lasted for about 4 months. I could feel him walking on the bed as soon as I went to bed, just like before. When my third cat died of old age, she came by the evening of the day she passed away and jumped on the bed where my second cat and her slept. He was with me in the living room and I know he heard her jump also, because he looked towards that door same time as me.

  • 09/22/2015 12:41pm

    I'd give just about anything to have a visit like that from my beloved Ragnar, who passed away in 2013. I can feel presences (and occasionally feel his), but would SO love to feel him walking on my bed again.

  • 10/23/2015 02:53pm

    I believe your comment about the ghost kitten. I am in a new apartment, when I lay in bed on occasion I will feel small paw prints of what feels like a cat or kitten walking across my legs or settling at the foot of my bed.

  • 08/17/2015 05:53pm

    what I learned on a show about cats on H2 is that they have the most keen sense of hearing of mammals incl. that of dogs which lead in the sense of smell so, your cats are probably hearing faint noises that you are not aware of, I know my cat used to hunker down in front of the kitchen, haunches twitching & ears straight up likely hearing the mice in the walls & she would only come into the kitchen when I opened the pantry door that her food was behind, there were two doors on the pantry but, she only reacted to that one

  • 09/17/2015 02:28pm

    Cats see other-worldly things too. I had a cat that saw a "demon" or some kind of negative/evil spirit near me when I was doing something kinda bad (partying) one time. She cussed at it and ran away to hide. I had never seen her freak out like that before. She wouldn't come out until I "exorcised" it from the house by rejecting/rebuking it. After I forced it (whatever it was) out of the house, she came back as loving as ever to me. I know that sounds crazy, but I have no doubt about what happened.

  • 09/25/2015 02:47pm

    The maximum acuity in cats is towards objects being approximately 30 inches or 75 cm away from them. Everything further away, appears more and more blurrier. And even objects 30 inches away do not appear sharp to cats. They "suddenly" see things behind you because they see a blurry item behind you and try to see what it is or it has just come into focus. They know YOU from across a room by scent and sound. They locate prey by sound and scent not by sight.

  • 09/25/2015 04:55pm

    Absolutely the article [i]does[/i] explain why your cats suddenly react to something you say is behind you! Your cats are seeing something that is only visible in the Ultra Violet bandwidth - and whatever it is they are seeing can not be seen by you, because a human's visual system is not capable of seeing in the Ultra Violet bandwidth - it is outside
    our visual perception. Do some studying on "Bandwidths" and it should then make sense to you. I had cats that did the same thing - in my case, I believe it was the spirit of a neighbor Chuck, an old man that had died that the cats loved. I'm not saying your entity is a ghost, but I have always conjectured that ghosts exist on a different dimension or bandwidth that we can feel, but we can't see. Sounds that we hear travel to us on a particular bandwidth. Bandwidths are rated at frequencies - when you learn about bandwidths & frequencies, a whole new understanding of the world around you should emerge - I'm pretty surprised you are so unaware of them that even after reading this article, you still made no connection - you are someone who has observed your cats clearly react to something unseen - then you read this article about their gift of sight - it should have followed that you made the connection; but you didn't. Please do yourself a favor and start self-educating yourself about the world around you - it is fascinating; at the very least.

  • 10/13/2015 04:44pm

    Most Cats can see stralght lnto the Splrlt world. The one before last especlally. was always looklng at 'thlngs' beslde or behlnd me ln the evenlngs.

  • Photo illustration
    04/26/2014 05:13pm

    How interesting that you used the photo of a blind cat for your illustration.

  • 05/05/2014 10:13am

    I don't think that is blind cat.. .I think the picture colors were edited :)

  • 10/03/2014 01:04pm

    Psssst - go to Photoshop, click on Image, then Adjustments, then Invert - it is a photo of a black cat with green eyes and gray-black whiskers.

  • 02/18/2015 02:00pm

    It's not blind

  • Blindness in Cats
    05/06/2014 01:54pm

    The colors may have been adjusted (the entire photo is sloppy), but the pupils are are totally expanded, which occurs in taurine deficiency and several genetic and medical disorders. This cat is blind.

  • 05/07/2014 01:50pm

    Cats eyes also dilate when a flash goes off when their photo is taken. Dilated eyes do not always mean a cat is blind.

  • 05/09/2014 09:07am

    Wouldn't a flash cause the pupil to constrict instead of dilate?

  • 11/03/2015 07:18pm

    Yes! Good observation

  • 05/09/2014 10:46am

    That's a picture of a black cat with green eyes. The colors have been inverted.

    Here's what happens if you switch it back.


  • 11/03/2015 07:22pm

    You are correct! It was done for the "creepy" effect.

  • 07/02/2014 12:19pm

    You're quick to jump to conclusions, so will I, you're a moron. I don't recall ever seeing a cat with a white nose and white tear ducts, but who knows what world you're living in.

    The picture colors have been inverted.

    The cat is black: http://snag.gy/nIPyx.jpg

  • 09/23/2015 12:27pm

    I cannot believe how mean everyone is being to someone leaving an opinion comment about the look of the cat! Is it really worth calling someone a moron because you don't agree with them? Just because people do not know your identity, does not give anyone the right to be nasty for no reason. The world has no consideration of others anymore.

  • 08/11/2015 04:20am

    You know nothing of photos. Did you read the article? The cat in the photo is in negative form. Pass your mouse over it, see how it says UV cat? Now, if you have Photoshop upload it, click invert image and you will see a very clear image of a black cat with yellow eyes and very small slits for pupils. Quit making assumptions.

  • 09/17/2015 02:34pm

    If the photo is doctored, then the white vertical slits are the actual pupils and they are constricted due to the flash.

  • UV cat
    07/14/2014 07:42pm

    The picture is of a cat as seen in ultraviolet light. :)

  • Interesting!!!
    09/17/2014 12:04pm

    Yes,it does seem that the picture was altered,but the article was very useful.Does anyone agree or are you just gonna argue over a cat picture?

  • You mean my dog can actua
    09/28/2014 01:35pm

    You mean my dog can actually see urine on the ground? How about ghosts? Can my dog see ghosts?

  • 12/06/2014 06:47pm

    Do, but he can see dog urine :)

  • Silly people!
    11/16/2014 06:35am

    You people are silly. The image wasn't edited, the entire picture was simply inverted.

    It's a black cat, with yellow eyes.


  • 08/05/2015 12:53am

    Really? I see a gold cat with blue eyes.

  • they do indeed
    04/01/2015 09:14pm

    Almost all of my dogs have demonstrated an awareness of something I cannot see, to the point of distraction. They watch open doors, reacting often to ???. They go down hallways with trepidation, looking, anticipating to see something they'd rather not see. However, one of my dogs was particularly "insightful". My "hyper-obedient, do whatever was commanded, needed to be by my side" dog was my constant companion. One day, when walking on trails in remote woods, we walked everyday, she stopped cold. Could not be dragged, coerced, ordered, enticed to go one more step. I took heed. We went the other way. She resumed her typical frenetic adventure. One evening, going to our cozy room where we'd spent hours of days, she refused to even enter the room. Paws planted could not be dragged. Wouldn't look up, nearly cowered, had to be carried dead weight into the room. This remained a near disturbing mystery until I learned that the construction we were doing on that room, in our 100 yr old home, could well be a trigger for paranormal activity. I'd say, the trigger was pulled.

  • 07/31/2015 05:26pm

    My German Shepherd puppy, who was about 6 months old at the time, was walking around the reservoir and we came to an area where she started going off the path that we walk on and started growling and walked all the way to the other side of the road, the entire time growling and keeping an eye on one central location and once we passed it, she was still continuing to look back and growl but I still did not see anything. Whatever it was, was not friendly and she kept distance between us and it. The next time we went around the reservoir, she approached that same area with caution but with a different reaction because whatever had been there before was not there any more and she went to investigate where it had been. It really makes me wonder what it was....whether it was an animal that had passed or human....but there was definitely something there.

  • Always thought infrared..
    05/08/2015 02:49pm

    It seems that our cats would always go directly to the warmest spots...so we just assumed they could see in infrared!!!

  • 05/17/2015 08:49am

    I always believed that cats, dogs as well as other creatures can see a broader range of the electromagnetic spectrum than we humans can. How far in either direction we may never really know.

  • In the wild
    06/01/2015 02:21pm

    I know dogs and cats see more than we humans do. I also know some animals in the wild also see a differant spectrum range. I am a hunter and know deer and elk are color blind as discovered by scientists. But in their vision I think they can depict colors better in black and white and greys to a better degree than we can. All in a spicies are not equal as in humans so don't expect your pet to be able to what others do, they all have their limits. I have seen wild animals detect camo clothing out of folage, but movement is animals primary visual indicator as in seeing whats behind you. I studied optics in the service and there is a prisim of beauty that we are limited from. Go ahead and debate the photo, its entertaining how easily people loose their "focus." Those with eyes see and those with ears hear, looking is not seeing.

  • The pic of the Cat
    08/25/2015 10:26am

    For all those who think that the cat in this article header is blind....that is not the case...the pic has been taken with an ultraviolet filter.
    Common sense is not that common.

  • This expains it
    09/02/2015 02:24am

    My dog Maya, a Labrador mixed with something else I think some kind of terrier, acts very strange whenever I try to take her picture with my phone. She slinks off and hides. When we first brought her home from Anti Cruelty a little over a year ago she would let me take pictures but she always acted like I was pointing something at her that she didn't like. She would always look away or turn around completely. I often wondered if she could see the beams that the camera uses to auto focus. Now if I just pick up the phone for whatever reason Maya will get up and leave the room lol. I was never mean to her or tried to force her to stay and get her pic taken so I am sure it isn't because she is afraid of it for anything that I have done.

  • 09/23/2015 10:50am

    I wonder if she had been abused by someone using similar objects. They may have thrown them at her or something. My dog Mia, a rescue Australian Shepherd is deathly afraid of water being on her and this includes a bath and she is scared to death of thunder and rain. I wonder if someone left her in a thunderstorm or somehow scared her with water perhaps a waterhose.

  • 11/26/2015 07:22am

    Just maybe her former owners were making dog porn and she did not want to be compliant anymore...
    Or the pictures made her backside look big

  • Cats can see unseen
    09/23/2015 10:43am

    My cat often stops and looks down my hallway with ears pointed toward the hallway as if she sees something.I have looked and I see nothing or hear nothing. I do not have mice or other animals in my home so i know she is actually seeing something. I did have a scare not long ago I was in one of the back bedrooms and I distinctly heard a woman's voice saying "Helloo" as someone that was announcing their arrival. My dogs were with me in the bedroom and heard it as well. I went into the hallway saying "who is it" because I was not expecting anyone and saw nothing the dogs went to the door and acted confused because they saw nothing. This gave me cold chills.

  • UV proof hunting clothes.
    09/26/2015 08:48am

    I need to invent UV proof hunting clothes.

  • SkepticSteve
    09/27/2015 07:45pm

    Ok... someone please explain to me why ghosts would be visible in UV but not other visible spectra of light.

  • 10/25/2015 12:13pm

    It's too much of an in depth explanation to answer fully or with the correct terminology here, look it up though because it's true.

  • 11/04/2015 02:37pm

    Why is it too hard to explain? That there are no such things as ghosts? Dogs and cats react to all kinds of stimuli and do not rationalize as we do.

  • 11/06/2015 11:34am

    Everybody has the right to their own opinion. I personally believe in ghosts, you obviously don't. Arguing about it here does nobody any good, research it yourself instead of depending on asking questions and wanting answers from people who are just sharing their own opinions and experiences. Why keep the pot stirred? Seriously, its all good. :)

  • What did my cats & I see
    10/23/2015 01:40pm

    I woke up one night to my cats growling at the end of my bed. I woke up to see dark shadows climbing to the corner of my ceiling, I thought I was seeing things so I turned on my light & once I did all of the shadows froze and looked at me, I thought I was hallucinating cause my DR had prescribed me a sleep medicine but then I looked at my cats to see them looking at the same wall, the same corner, and once the light was on all their hair stood up on them they growled, hissed, were showing their teeth and batted their paws in the air and bolted out my door. The shadows dashed up into the corner and disappeared. I didn't know what to think, I just sat up on my bed and sat there staring at the wall thinking in my head: WHAT JUST HAPPENED!!! My Medicine I was prescribed did have the side effects of hallucination BUT my cats seen it too!!! They wouldn't come in my room for days after that.

  • What did my cats & I see
    10/23/2015 01:40pm

    I woke up one night to my cats growling at the end of my bed. I woke up to see dark shadows climbing to the corner of my ceiling, I thought I was seeing things so I turned on my light & once I did all of the shadows froze and looked at me, I thought I was hallucinating cause my DR had prescribed me a sleep medicine but then I looked at my cats to see them looking at the same wall, the same corner, and once the light was on all their hair stood up on them they growled, hissed, were showing their teeth and batted their paws in the air and bolted out my door. The shadows dashed up into the corner and disappeared. I didn't know what to think, I just sat up on my bed and sat there staring at the wall thinking in my head: WHAT JUST HAPPENED!!! My Medicine I was prescribed did have the side effects of hallucination BUT my cats seen it too!!! They wouldn't come in my room for days after that.

    10/26/2015 01:48pm


  • Ghost Kittens?
    11/07/2015 03:27am

    Ghost kitties? Your dog seeing your dead neighbors? Best one was the mans cat that saw a demon while he was partying. I think many people are on the wrong MD site

  • 11/26/2015 07:32am

    I once took an allergy medicine that made me able to see the fluorescent light bling at 60 cycles...
    Nothing to do with the story, however I once threw a paper clip in a 7-up bottle from six feet on the first try... It gave me a sense of Nirvana

  • My cat
    11/14/2015 05:47pm

    My cat see's dead people

  • my
    11/14/2015 05:49pm

    my cat see's dead people

  • I noticed this
    11/18/2015 09:50am

    I was amused watching my cat jumping and attacking nothing. So, I got out my phone to record it, and in the recording there were bright spots of light she was playing with, that I couldn't see with my eyes, but they showed very bright and clear on the phone camera.

  • animals and spirits
    11/25/2015 01:03am

    I have seen several times when animals have reacted to spirits, but none was more startling to me than one night when I was deep into a novel and suddenly the sound of breaking glass seemed to be coming from our second floor. We are not talking about a little glass, but like someone had taken a hammer to several dozen picture windows. My dog Butch was laying by my feet, and at the sound of the breaking glass he quickly raised his head. I was about to start running around climbing stairs and searching for the source of the sound, but Butches behavior stopped me. Butch was extremely well trained by his first owner and had all the instincts and abilities you would expect of any well trained police dog, or guard dog. He patrolled our house with precision, as if he had an internal clock that would send him on his rounds, and he would check out each room paying particular attention to my children's rooms. Any hint that any of us was in any parole of any sort, and his hackles rose, and he immediately would go into his defense mode. I had learned from experience to trust this dog with my life if need be because I knew he would never fail me. Only now with only a slight tilt to his head, after the noise stopped, he simply laid his head back down. Our house was in fact home to more than just my family and our pets, we also had several spirits that dwelled there in, and while I had grown accustomed to them over the many years I had lived in this house, I was surprised that the dog, without even checking on what had happened, quickly dismissed all that noise. I guess what he saw, and what he heard explained it all to him without the need to go and check it all out. By the way, there was not even one tiny shard of broken glass ever found in any of the rooms of our old rambling house afterwards.