Transcript
Are dogs really colorblind, or is that just an urban legend? Researchers found a way to test it. Welcome back to What the Science, Doggy Vision Edition. And trust me, it's gonna be a real eye-opener. This is an eye, it's similar in structure with most mammals. Light comes in through the cornea and your lens focuses it as it passes through the pupil. It then hits the back of the eye where the rods let us see the low levels of light in black and white vision, and the cones let us see brighter light in color. We have three kinds of pigment in our cones. each sensitive to different wavelengths of light, centered around red, green, and blue. Our brains combine the different activations of each type to give us the final output color. For example, we perceive yellow light when the red and green cones are equally activated. Fun fact alert. Did you know that our cones can actually see UV light, like from a black light? To bet our lenses are party poopers and filter it all out. But in cases where the lenses are removed, like for cataract surgery, the people report vivid and detailed vision in the UV. It's like a super power. And dogs are similar. This study found that dog lens transmit over 60% of UVA light. And they have more blue cones than we do, which likely makes them more sensitive to the different shades of blue light. Maybe that's why they always know when you're all feeling blue. Daboddy, double, dot. But dogs only have two types of cones, compared to our three, which we theorized would make them like humans who are red-green colorblind. And in this study, researchers developed a way to test it, using a modified version of the human colorblind test. They had dogs look at a screen with this flashing green background on one side, and the other side having the same background, running cat on top. They found that the dogs focused more on the running cat version when there was a high brightness contrast. But when it was just red on green color with the same level of brightness, they couldn't tell the difference between the two circles, just like human colorblindness. So yeah, showing chewy bluey is truey, not screwy. Share this with all the dog lovers out there.
Additional notes
Some other fun doggy vision facts: 👉 Dogs have worse visual acuity than humans: the ability to clearly make out all the details of an object (four to eight time worse than humans). This is due to to the different neural structures of the dogs' eyes, especially the fewer connections of the rods to the ganglion cells and the smaller number of optic nerve fibres 👉 Dogs see brightness differences roughly half as well as humans 👉 Dogs focus on faces of other dogs, but not really the faces of humans 📚 MAIN STUDY - DOI: 10.1098/rsos.170869 #stitch with @Jaclyn Byrne #dogs #doglovers #Longervideos #science #edutok #bluey #dogsoftiktok #dogvision