See the World Through Their Eyes

Today is World Animal Day. The theme this year is See the World Through Their Eyes, so we decided to take it literally.

On the left is a photograph of two of our Shih Tzu puppies, taken on an ordinary afternoon. On the right is the same photograph, processed to approximate what a dog’s eyes would make of that scene. Same room, same blanket, same toys.

The red blanket has turned to khaki. The green dinosaur has all but dissolved into the background. The blue octopus is still unmistakably blue — and the puppies themselves look almost exactly the same.

Why the fourth of October?

The date belongs to Francis of Assisi, the patron saint of animals. The day itself belongs to a German writer named Heinrich Zimmermann, who edited a magazine called Mensch und Hund — Man and Dog.

Zimmermann wanted 4 October for his first event. He could not get the hall, so the first World Animal Day was held in Berlin’s Sportpalast in March 1925 instead. Five thousand people came. He finally got his date in 1929, and in May 1931 an international congress in Florence adopted it worldwide. One man, one magazine and six years of persistence — and now it is marked in dozens of countries.

What your dog is missing

Human eyes carry three kinds of colour receptor. Dogs carry two, with peak sensitivities near 429 and 555 nanometres — roughly blue and yellow-green. Everything in between has to be inferred from just those two signals, which means red and green end up producing almost the same answer. The research that settled this was done in the late 1980s by Jay Neitz and colleagues, whose colour vision lab is now at the University of Washington.

The practical consequence is in the picture above. A red ball on a green lawn is, to your dog, a dull brown object lying on a dull yellow-brown field. When he runs straight past it, he is not being stubborn or slow. He genuinely cannot pick it out.

Buy blue or yellow toys. Those are the two colours he sees most vividly, and the difference in a game of fetch is immediate. Most toys are made red and orange because those colours sell to humans.

What you are missing

Colour is the one contest our eyes win. Everywhere else, we are the ones in the dark.

Smell. Depending on the breed, a dog carries somewhere between 220 and 300 million olfactory receptors. We have about five million. The share of the brain given over to analysing scent is some forty times larger in a dog than in us. The two nostrils sample independently, so a dog smells in stereo and can tell which direction a scent came from. There is a second organ as well — the vomeronasal, or Jacobson’s organ, opening into the roof of the mouth — devoted to pheromones alone. And those receptors renew every month or two, growing denser for the odours a particular dog actually meets.

Light. Behind a dog’s retina lies a reflective layer, the tapetum lucidum. It is what makes their eyes flare green in a photograph, and it gives every photon that missed a receptor on the way in a second chance on the way out. A dog is comfortable in roughly a fifth of the light we need.

Width. Our field of view is about 180 degrees. A dog’s is between 240 and 270. He is watching the cat behind him without turning his head.

Four things worth doing with this

• Change the colour of the toys. Blue and yellow, not red and orange. It is the cheapest improvement you will ever make to a game of fetch.
• Let him sniff on the walk. A walk where a dog is towed past every interesting smell is exercise. A walk where he is allowed to stop and read is the thing he actually came out for. Ten minutes of sniffing tires a dog more thoroughly than a brisk half hour on a short lead.
• Believe the nose before the eyes. If your dog is certain about something you cannot see, he is probably right. He is working from better information than you are.
• Remember how low he is. A dog meets Cyprus from about forty centimetres off the ground, which in August is the hottest part of it. Press the back of your hand to the tarmac for five seconds before a midday walk. If you cannot hold it there, neither can he.

The part that is not about dogs

The theme was suggested by a reader in the UK named Zoe, who put it better than we could: “In a planet ever-affected by a changing climate and the consequences of human activity, it is important to remember that it is not just us that are impacted — it is animals.”

That is the whole idea. Not sentimentality, but a change of vantage point — making decisions from where the animal is standing rather than only from where we are.

For us it is a working principle rather than a slogan. It is why every puppy leaves with its vaccinations finished rather than started, why the veterinary checks happen twice and not once, and why we would rather talk someone out of a breed than sell them one that will be miserable in a third-floor flat in Limassol in July.

Happy World Animal Day — and if there is a dog near you right now, there is a good chance he already knew. He could smell you coming.

Sources

• Naturewatch Foundation — the World Animal Day 2026 theme
• Neitz, Geist & Jacobs, “Color vision in the dog”, Visual Neuroscience, 1989 — PubMed
• American Kennel Club — Can dogs see color?
• PBS NOVA — Dogs’ dazzling sense of smell
• The simulation uses the Viénot, Brettel & Mollon (1999) dichromat projection, applied in linear light. It is an approximation of canine vision, not a photograph of it.