Have you ever watched an action-packed scene unfold around you and you try your best to focus on a certain object moving? Or have you ever watched your house cat hunt and noticed that they don’t lose focus of what they are chasing in front of them?
I asked the question whether this is discipline or is it a predatory adaptation that happens automatically? After mulling over it for a while, I did some research.
A male leopard chasing a herd of an impala, as you can see here he has locked on his target while an explosion of animals happens around him.
I found an article on the pupils of land animals by researchers at the University of California in Berkeley and how they have adapted their eyes due to their niches. They tested the pupils of 214 species of land animals, both predator and prey.
Predators on land have eyes facing forward, giving them the ability to focus on their prey.
Prey species on the other hand – but more specifically many herbivores – have eyes facing to the side, giving them great peripheral vision. Interestingly enough, it is their pupils that can differ the most between species, conferring different advantages upon them.
Some animals have a round pupil, like us, some have a vertical slit-shaped pupil and some have a horizontal slit-shaped pupil.
Predators that ambush their prey and hunt both day and night tend to have vertical slit-shaped pupils – like a house cat. The researchers then concluded that the shape of the pupils depends on how the animal hunts. However, lions and leopards are also ambush hunters, yet their pupils are round. Researchers then concluded that predators that have round pupils are more “active foragers” since they chase down their prey. This confused them too so they furthered their research. They found out that pupil shapes are not only dependent on the predators’ hunting techniques but also their size.
Being closer to the ground, making it difficult to focus on the object in front of them (it’s difficult to focus on prey when you’re much shorter than the grass/logs), smaller predators need to use “focus blur” which will help them judge the distance more accurately than taller predators. That I found incredible! We, like taller predators, don’t have that much worry of tall grass getting in our way so we don’t need to use focus blur as much to judge distance, hence our circular pupils.
An African Wildcat which has vertical slit-shaped pupils, notice how small it is compared to a leopard (with circular pupils).
But what about the prey species’ pupils? Most prey animals, like antelope and especially grazers, have horizontal slit-shapes pupils. The researchers used technology to see exactly how these animals see. They saw that the horizontal slit-shaped eyes allowed them to see in perfect alignment with the ground as they feed and more light is let in from the front, the sides and behind them. Not only does this help them spot predators in their periphery, but if/when chased, it allows them to have superior collision avoidance, detecting obstacles that might cause them to stumble while running.
They say the devil’s in the details, but when it comes to the different pupil types in the wild, it’s more like life and death that you can find in the details!
Jess, wonderful story🤗
I never knew that about cats, I have seen my daughters cat – and he has been side slit pupils!
Fascinating Jess. I’d never thought about the pupil design of predator or prey…. always something to learn.
Frankly I have never given much thought to the pupil’s shape and the rational behind it. Facinating information. Your images are truly stunning!
Simply stunning pictures, and revelations!
Great article, interesting. Thanks!
Amazing information. The Londololozi blog is one of the few sites that make research information appealing❤
How about a few close-up photos like these that clearly show how you designate the leopards by number, 3-3, 3-2, etc etc
A very interesting blog Jess. A lot of what you said does make sense for both predators and prey. Wonder if the same applies to raptors?? Thanks for sharing this with us. Enjoyed reading it.
I never think much about different pupils of eyes! This has been a most interesting read, Jess. Thank you so much!
Wendy M
Interesting blog Jess.
Another interesting, informative blog Jess. More for us to learn. Thank you.
Thanks for digging into this topic and sharing what you’ve found out in such a clear and concise way. Fascinating that smaller predators have better blur control, while the grazers are excellent “obstacle avoiders.” Send more insights if you have other observations in the bush that are worth investigation!