How would it affect a human to suddenly have the visual senses of a martial eagle?

Question

With the help of my allmighty Handwavium I want to change the biology of a human being so that this particular human being gets his eyes replaced with the eyes of a martial eagle. According to Wikipedia

Martial eagles have been noted as remarkable for their extremely keen eyesight (3.0–3.6 times human acuity). Due to this power, they can spot potential prey from a very great distance, having been known to be able to spot prey from as far as 5 to 6 km (3.1 to 3.7 mi) away.

The human in question gets this ability via handwaving. Just like in the last installments of my little series "How would it affect a human to suddenly..." "... hear like a cat?" and "... have a sense of smell comparable to a wolf?" the process can be ignored and the individual is not directly affected by the change so that he can continue with his normal life. Other people won't directly realize that this individual has the eyes of a martial eagle instead of his own.

The setting is Europe and we will imagine this human to be a middle-class white-collar worker. If an average human would, from one day to the other, be able to suddenly have a far better visual sense than other humans - what would be the biggest problems this human would have to face in his everyday life?

Answer 1

There will be several effect and acuity is the least of them.

Color will be a bigger effect than acuity, birds see more base colors than we do. Many things will suddenly be the wrong color, especially blues, blacks, and purples (to us). Additionally there will be several completely new colors we don't even have words for since they can see into the ultraviolet.

Diurnal birds also have worse night vision than humans (fewer rods), so your guy will likely experience night blindness.

Birds have something called a Pecten oculi which supplies nutrients to the eye and will mean they have a bigger blind spot, this will not have much effect unless they are close to something and looking up at the same time however. Oddly this may also be allow birds to detect magnetic fields, how this would translate to vision is anyone's guess.

Visual acuity will not have much effect. The amount of the brain devoted to processing visual information is not any larger and with the increase in incoming information (new color and magnetics) it has to process your human may actually experience a lose in acuity, not a gain.

Answer 2

Let me answer this from personal experience.

While I am not eagle-eyed, I had been blessed with a vision that's better than most people have (and my brother's vision is even better than mine).

First of all, good vision does not provide any "superpower" equivalent. An average human equipped with a pair of binoculars or magnifying glass would always be better than an "eagle-eyed" human. Such a human, however, would have an edge among peers in sports, particularly in shooting. While I never particularly excelled in shooting, I never doubted that I had an aptitude for it, and, should I choose to practice, I might have achieved some success. An eagle-eyed human can potentially become a champion shooter. However, eyesight is not the everything in this sport.

Good eyesight provides convenience for everyday life - you don't have to come close to be able to read a posted note, you don't have to get the best tickets to enjoy the show, if you accidentally drop something small, you don't have to get on your knees to find it.

Also, you can exploit other's expectation of privacy. You can see what other people writing or typing when they assume you are too far away to be able to see anything. An eagle-eyed human can make a criminal or spying career by stealing passwords and other important information.

There are some things that can be called inconveniences. For example, I've been always too much distracted by the black grid of plasma TVs. Gray grid of an LCD is much more pleasant to an eye. Also, I've always been too keen to spot foreign objects and insects in mine or someone else's food. One or two incidents may be exciting, but after a while you'd get a dubious reputation among your friends and start wondering whether it's better to keep quiet.

Answer 3

The biggest problem with increased visual accuracy would be that images of things which are essentially made of dots (photographs, printer output, computer displays), would look like they are made of dots and this could be annoying. Think of reading stuff from a old dot matrix printer or and old low resolution computer display.

I am assuming you don't have a processing problem because the handwavery takes care of that the human still only has a human visual arc because the eyes are redesigned to be in the front of the head as opposed to the side as with a eagle. Both these could be problems if not corrected for.

Note also eagles can distinguish more colors which is not the same think as visual acuity.(thing the opposite of colorblindness eg "I know everyone tell you that scarf matches those pants but they don't") please excuse my spelling disability

Answer 4

Keep in mind that an eagle has unique eyesight, fine tuned for its particular living conditions.

Eagles have a high density of photoreceptors at the center of their retina. This gives them a magnified spot in the center of their vision, but good wide angle view as well around the periphery of their overall vision.

That is optimized for aerial hunting - wide angle to look for movement, with a magnified spot in the middle to fully identify the moving subject.

Actually carrying out an attack can be dangerous to the hunter, there is the possibility that the hunter can become injured (which to a bird of prey is pretty much a death sentence) if they attack an animal that can fight back, like a big cat, or canine. Or that magnified view might also reveal a ground based predator nearby that could take down the eagle as it attacks its prey.

So the ability to fully identify the target and any ground based predators nearby before committing to an attack is a big bonus.

Now, how does that benefit a human? Might be of benefit to a soldier that can attack from a distance, say an expert archer. Otherwise, that magnification spot in the middle of their field of view probably wouldn't do the average human a lot of good. Humans, being capable of building and using tools, can always carry binoculars.

Answer 5

The answer: distraction. The “new” sources of visual data would overwhelm the individual at first as their brain struggles to process and make sense of this sudden change. Some familiar objects will become unfamiliar as details long ignored reveal themselves, maybe for the first time. All of this would go far in disturbing their equilibrium perhaps for weeks after that. But thanks to a documented brain phenomenon called plasticity, he or she would eventually adapt and carry on with his or her life. Perhaps new career pathways, hitherto inaccessible to this person, will then open to them… or not. Of course, this outcome assumes that the individual is resilient and can come to accept such a drastic change in perspective. If that isn’t the case, then they’re screwed. Some people never adapt for one reason or another.