The Alien Beauty of a Cat’s Gaze

Why a cat’s eyes seem so uncanny – and what their structure has in common with snakes.

Photo by author

There are galaxies behind the eyes of a cat.

Look closely – closer than comfort might allow – and you’ll see it: a vertical slit cut through molten gold, ringed by darkness, reflecting worlds. This isn’t just an eye. It’s a finely tuned instrument shaped by millions of years of evolution, a marvel of biology that also feels like a portal to something older, stranger, and deeper than science can measure.

I took a photograph of my cat’s eye the other day, a macro close-up that showed every fleck of pigment, every glint of reflected light, every detail of that narrow, reptilian pupil. What I captured didn’t just feel alive – it felt sentient. Not just looking back, but through me.

Cat eyes are engineered for the in-between: for dusk, for shadow, for the moment just before something moves. The vertical pupil allows for rapid dilation and contraction, giving cats a huge dynamic range when it comes to light sensitivity. They can stalk prey in near-total darkness or blink lazily in the midday sun, adjusting seamlessly to the light.

Behind the retina lies the tapetum lucidum, a reflective layer that bounces light back through the eye a second time. It’s…