Why Are Pallas's Cat Pupils Round? Differences from Other Small Felids and Eye Secrets

The Pallas's cat's pupils remain round and shrink

The Pallas's cat's pupils stay round even in bright light. While domestic cats have vertical, slit-like pupils in bright light, the Pallas's cat keeps its round shape, shrinking or expanding in size.

The Columbus Zoo in the United States explains that the Pallas's cat's pupils "shrink into a small circle rather than the vertical, elongated shape commonly seen in many felines." The Edinburgh Zoo in the United Kingdom writes that "while all other small felines have vertical pupils, the Pallas's cat has round ones," and that this is one reason why it looks "unhappy."

In Japan, the publication materials from Nagoya City (Higashiyama Zoo and Botanical Gardens) state that "the Pallas's cat differs from other felines in the number of teeth and the shape of its pupils."

The key point is that the Pallas's cat's face looks "narrow-eyed" because its pupils are round. Since it lacks vertical, slit-like pupils, it gives an impression similar to human eyes. Along with why the Pallas's cat looks round, this facial expression is one of the reasons for the Pallas's cat's popularity.

Why Do Pallas's Cats Have Round Pupils? What Research Has Revealed

There is no clear answer yet as to why the Pallas's cat has round pupils. However, there is research that explores the relationship between pupil shape and lifestyle.

In 2015, researchers from the University of California, Berkeley, and others studied the pupil shapes of 214 land-dwelling animals. Their findings are as follows:

• Vertical, elongated pupils are common among ambush predators that are active both at night and during the day.
• Of ambush predators with vertical pupils, 82% were small animals with shoulder height under 42 cm.
• Round pupils are common among animals that are active during the day and chase their prey.

According to the researchers, vertical pupils help measure distances to prey using eyes close to the ground. By clearly defining the vertical edges and blurring the horizontal edges, distance becomes easier to judge. The researchers also mentioned in an interview that while domestic cats have vertical pupils, large felines like tigers and lions do not.

What stands out is the Pallas's cat. Although it is small and hunting is mainly ambush-based, this study suggests it should have vertical pupils, yet it actually has round ones. In other words, the Pallas's cat is an exception to the overall trend found in this study.

Notably, the 2015 paper does not mention the Pallas's cat. There is no research that directly investigates why the Pallas's cat has round pupils, at least within the scope of this search. While explanations such as "suited for measuring distance in open grasslands" are sometimes mentioned, they have not been confirmed by research, so this site will not claim to know the exact reason.

The Pallas's Cat's Eyes Are Positioned High on the Face

The Pallas's cat's eyes are positioned higher on the face compared to domestic cats. The Smithsonian National Zoo explains that this may help in spotting prey in the snow.

According to materials from Nagoya City, the Pallas's cat's face is described as "having a high forehead and round ears positioned low and far back." The high eyes and low ears form a configuration that is well-suited for looking for prey by slightly lifting its head from atop rocks.

There is also a mechanism that protects the eyes. According to the Columbus Zoo, the Pallas's cat has a nictitating membrane (a semi-transparent eyelid that comes from inside the eye), which protects the eyes from cold and dust. The central Asian highlands where the Pallas's cat lives can drop to below -50°C in winter. This protective mechanism is essential for living in the Pallas's cat's habitat.

What Is the Vision of the Pallas's Cat? What Is Not Known

There is no research that has measured the vision of the Pallas's cat, at least within the scope of this search. While we often hear that the Pallas's cat has "good eyesight" and "good hearing," there is no data to confirm this numerically.

In the field at zoos, there are such observations. A blog post by a keeper at Saitama Children's Zoo and Nature Park mentions that the Pallas's cat often notices the keeper before they arrive at the enclosure, hiding inside the building. It is clear that the Pallas's cat is very sensitive to sound and movement.

Tips for Observing the Pallas's Cat's Pupils at a Zoo

If you want to actually see the Pallas's cat's pupils, the bright outdoor enclosure is the best place. In bright light, the pupils shrink and become small, making the round shape clearly visible. In dark indoor areas, the pupils become large and open, making it hard to distinguish the difference from domestic cats.

When observing, the moment the Pallas's cat turns its head toward you is the best chance. The Pallas's cat sometimes raises its head just slightly from behind a rock and stares at you. At that moment, you can clearly see the small, round black pupils and the bright-colored iris (the colored part around the pupil). If you want to take a photo, using a telephoto lens from a little distance will help avoid startling the cat.

Even though the Pallas's cat has round pupils, the impression is different from that of lions or tigers. This is because the Pallas's cat is small, has a flat face, and has low-set ears, making its eye position resemble that of a human face. What Is the Pallas's Cat Like? summarizes the facial features of the Pallas's cat.

Places in Japan where you can see the Pallas's cat are summarized in Zoos in Japan Where You Can See the Pallas's Cat. Individual names are listed in Names of the Pallas's Cats in Japan.

Sources

• Columbus Zoo: Pallas' Cat (Pupils, Nictitating Membrane)
• Edinburgh Zoo (RZSS): Pallas's cat
• Brookfield Zoo: Pallas's cat
• Nagoya City Press Release: A Pallas's Cat Baby Was Born (June 24, 2025, PDF)
• Banks et al. 2015. Why do animal eyes have pupils of different shapes? Science Advances 1(7)
• The Christian Science Monitor: The eyes have it (August 8, 2015. Researchers' comments)
• Smithsonian National Zoo: 10 Fascinating Facts About the Pallas's Cat
• Saitama Children's Zoo and Nature Park Blog: ZOO Meeting ~ About the Pallas's Cat at SCZOO (May 6, 2023)