Cat's up close vision is blurry. Why did evolution give cats whiskers instead of perfect eyesight?

Cat's up close vision is blurry. Why did evolution give cats whiskers instead of perfect eyesight?

petmd.com/cat/behavior/evr_ct_why_do_cats_have_whiskers

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en.wikipedia.org/wiki/Saccade
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bc u touch urselfff

Just a guess because I'm too lazy to look it up (as are you, apparently) but I'd say it's because they're crepuscular/nocturnal hunters, and sensitive whiskers are more useful than eyes in low light conditions.

Because the most useful evolution isn't always the one that will develop.

Practicality is subjective. Maybe objectively the most useful thing will develop

cats have some of the best nightvision in the animal kingdom, though.

this is the correct answer

But grow whiskers? Instead of perfecting the specifics of an already convenient asset?

evolution found the sensitive whiskers idea before a solution to sharp AND good nocturnal vision, thereby taking off the pressure from having to develop terminator vision at all. plus, whiskers work even in absolute darkness, and once you stick your head into a hole you won't have enough light to see by it anyway.

Because RNG and it worked well enough.

Evolution in a nutshell.

Partly the same reason your camera does not have both microscopic and super zoom - cuz it's hard to focus a single lense for both super near and super far vision. More importantly, however, your camera's survival does not depend on what it is focused on.

Predators are almost universally far sighted, while herbivores very often near sighted, often with a grander color range. Herbivores don't have to sneak up on their food, they only have to identify its suitability when close up. Predators don't give much care as to the state of their food, prioritizing instead on catching it.

It's also the reason you, as a primate, don't have 200x zoom letting you see bacteria. Being so narrowly focused would be counter-productive to your general survival as a scavenger. You can see well enough close up to manipulate fine objects with your hands and identify fruits, and far enough to spot predators, but you have neither the microscopic vision nor telescopic vision, as either focus is all but useless in our natural environment.

And, finally, yes, evolution isn't always the most optimal - just whatever gives you a slight edge and doesn't hamper your potential to breed, so each animal tends to have a focus field well suited to its survival, rather than universally perfect vision.

Sounds all too rational to me. Who do ypu think you are

Cats have a reflective layer behind the retina.
That's why their eyes glow-in-the-dark.
Light which passes through the retina is bounced back and has a chance to fire a nerve cell on the second pass.
This results is better night vision -- but also "doubles up" the image. First pass and second pass are at different distances from the lens, so they can't _both_ be in focus at the same time.
Not serious for distant objects though.

So both the asset -nightvision- and compromise -up close eye sight- are a direct result of one another's working mechanism. They are mutually exclusive

Pretty much.
Evolution stumbles along, modifying existing structures and re-purposing them for new uses.
That's why we have all sorts of flaws.
If you were building a camera you'd put the CCD chip at the focal plane and run the wiring out the back. Right?
In the human eye (in all mammalian eyes, I think) the wiring is on the FRONT of the retina, partially blocking the light. The wires all run together to form the bundle of the optic nerve and then the nerve has to pass THROUGH the retina to get out the back.
The spot it goes through is your "blind spot". You can't see anything there. You don't notice it normally because your eyes flick all around a scene and build a complete mental image. Your mind edits the blind spot out. But there are easy ways to demonstrate it.

The octopus eye evolved separately and is organized logically, wiring at the back end. Eyes have evolved from light-sensitive patches 50 or 60 distinct times here on Earth. Vision is such a useful tool for survival.

Whiskers: very low space cost, insanely low energy consumption, low processing

Perfect eyesight: high cost, high energy consumption, high processing

Useless

How does the mind fix this Blindspot? And why so?
Was this in itself a process in time, where once in actual fact humans just blatantly experienced this evidently compromised peripheral vision?

Key to understanding your vision is to know the eye doesn't work like a camera - or rather, the eye does, but the brain putting that image together does not. For starters, the source image is upside down.

The brain is less a video recorder, and more an object recognition system. It doesn't "see" a bunch of pixels made up of exposed rods and cones, rather it recognizes patterns among them and says, "Oh, that's dad.", or "That's a car.", etc. This is why, among other things, you occasionally mistake people for folks you know, or mistake an object in the distance for a person, but realize it's assemblage of some other objects when you get closer, and the like. ...and of course, why certain drugs or exhaustion can make you hallucinate while having no physical effect on the eye itself, why you see faces in clouds, etc. Like everything else in the brain, it's complex pattern recognition.

It's also among the reason eyewitness testimony tends to be unreliable as fuck - the brain doesn't record information - it instead, puts a story to the data based on previous experience and what it assumes is happening. Further, the memory of that experience can be altered by additional information, as the brain tells the story, processing it again, as it remembers it based on already processed patterns.

If you Google "blind spot test", you can see this blind spot is fairly narrow and not debilitating. (Mind these tests don't work real well on a computer monitor, helps to have a white background to go with the white +/• image.) It's normally very simple for the brain to guestimate what's within that spot based on the objects it overlaps or are around it. In the case of a blind spot test, it just has nothing else to work with, other than the white area, so it "covers" the dot with white. This is also why you don't see a blind spot when looking at wallpaper - the brain just assumes the color pattern continues, and fills it in accordingly.

That memory based vision also leads to fun things like this.

...and of course, many such optical illusions work on cats too... Our visual processing systems apparently aren't much more different than our eyes.

>cats have some of the best nightvision in the animal kingdom, though
absolutely not true, their vision is average at best
animals as simple as jumping spiders have way better vision than them and arguably better than humans

how did we even figure this out?
Moreover if you find out you're living in such a bizarre mind, how can you know the means of scientific research conducted is reliable itfp,,

Whiskers are a wonderful tool for the cats. Also there is no such thing as perfect eyesight.

A major part of why the scientific method exists is to eliminate the flaws in our perceptual ability. Certainly, even in the most ancient of times, we knew memory and experience were not always reliable, well before we dissected the eye and/or started developing tests and optical illusions, and knew it was entirely possible to fool people into believing false information.

You can wax philosophical about subjective experience or phenomenology, or as to whether an objective reality even exists, but we share enough experience to self-check one another, and build machines to filter out subjectivity to various degrees.

(Suddenly regret not being able to find that stick figure comic where two guys are arguing whether a flower is red, and one pulls out a spectrometer...)

It's all put together in your mind.
The area of maximum clarity, where the image is really sharp, is quite small, no more than 5 or 6 letters wide when you're looking at normal print. Your eyes jump all around the page. en.wikipedia.org/wiki/Saccade
But you aren't consciously aware of this. You think you're looking at the whole page.

I've seen a clever experiment. Subject is looking at text on a computer monitor while an eyeball tracker notes where he's looking. The parts of the page where he ISN'T focused change to completely different text. Different font, size, color, words. Onlookers staring at the same page over the subject's shoulder clearly see the "alternate" text. But the subject, who's being tracked, never notices the trick being played on him.

I'm pretty sure the pupil shape allows the eyes to adjust to changes in light quickly but is also the reason that they have poor close range vision. The whiskers make up for that though.

>0:53
dont know why but this shit makes me cringe HARD