Humans have a lot of advantages over animals.
We have languages, opposable thumbs,
and most of us are a lot smarter than animals.
Our eyeballs, as it turns out, are pretty boring.
Many animals have eyes that let them see the world
much differently than we do,
so let’s find out exactly how the animals of earth view the world!
Number 20, dogs.
We humans have three different kinds of color detecting
cells in our eyes, they’re known as cones,
whereas dogs only have two.
The cone cells that dogs have are only capable
of detecting yellow and blue-to-ultraviolet light.
Each type of cone contains a pigment that
is sensitive to a different wavelength of light,
so the range of color that an animal can see
depends on what combination of pigments they have.
Since dogs have fewer cone types,
they are not able to see as many colors as we can.
Many people believe that dogs see in black and white,
but that isn’t true.
A dog would see a rainbow as light blue, dark yellow,
light yellow, white, and very dark blue.
Number 19, geckos.
Human cone cells need pretty bright light
in order to function well,
which is why we can not see colors that well when it’s dark.
Luckily we also have rod cells which help us see in low light,
which has a single light sensitive pigment.
Unlike humans, geckos have great color vision
even in the dark.
Dark doesn’t even look that dark to them,
since their eyes are 350 times more sensitive to color
in low light than ours.
Geckos evolved to have these eyes because they hunt at night.
Number 18, giant clams.
As it turns out, giant clams not only have eyes,
but have a few hundred eyes about the size of pinholes
all along the edge of their bodies.
Their eyes are shaped like a cup and have very narrow openings,
and unlike our eyes,
they do not have a lens.
Giant Clams are sensitive to three different colors of light,
but they can not combine that information.
This means that they see colorful, but undefined images.
They can detect movement, however,
which is all they really need to get by.
If they see a nearby predator,
they can squirt a jet of water at them
or close their shell in self defense.
Number 17, jumping spiders.
Jumping Spiders are like regular spiders except worse
because they can quickly jump away from the newspaper
you’re trying to smash it with and they have great vision.
Like most spiders, they have eight eyes
with which to detect potential prey.
Their biggest pair of eyes faces forward
and gives them high resolution vision for seeing detail,
and their other smaller eyes toward the back of their head
to give them peripheral vision and motion detection.
Jumping Spiders can also see more colors than we can
due to their special pigments which are sensitive to ultraviolet light.
Number 16, Mantis Shrimp.
You’ve probably heard of the Mantis shrimp
because of their famous aquarium glass shattering
Well, as if they even needed other superhero-esque abilities,
it turns out they also have freakishly good eyesight.
In fact, they have one of the most elaborate eyes
of any animal on earth.
As mentioned before, humans have three types of cones in their eyes.
Mantis shrimp have 16.
Mantis shrimp can also tune the sensitivity level
of their vision at will to adapt to different environments.
Scientists have yet to discover another animal that can do that.
Who would have thought that the most intricate visual system
on earth would be attached to this weird shrimp?
Number 15, bees.
If you’ve seen the Bee Movie, you already know that bees are important.
But what you may not know is
that bees have 1,000 eyes as opposed to two.
Bees, like many other insects, have compound eyes
that are made of many ommatidia, meaning each act like an individual eye.
They all point in slightly different directions,
which gives bees a wider angle of sight than humans.
The image that bees see is not as sharp as ours,
but it does let them see up to 300 pictures per second,
versus humans, who can only see 65.
Number 14, cats.
If you’ve ever wondered why sometimes cats’ eyes
will be a different color in a photo
than they are when you look at’em,
this is due to the tapetum lucidum,
a reflective layer behind the retina
that redirects light back through the eye.
This works in the same way
that shining a light at a mirror
creates more light than shining one against a wall.
The tapetum lucidum means
that not only do cats see better in the dark,
but they actually see better in the dark than they do in the light.
Number 13, flies.
Flies can see limited colors,
but they have a very broad field of vision,
and see in a sort of mosaic effect.
The reason flies can seemingly almost always escape from
whatever you’re trying to kill them with,
isn’t because they’re psychic,
but because they literally see the world in slow motion.
They’re like Keanu Reeves in The Matrix,
except all the time.
This was discovered in a study that tested
different animals ability to detect separate flashes of fast-flickering light.
Scientists found that time perception
is directly related to size and how fast an animal’s metabolic rate is.
So the tiny fly, with it’s extremely fast metabolic rate,
can easily react to and escape your fly swatting attempts.
Number 12, snakes.
Some animals, like snakes, don’t see color at all.
Snakes that spend most of their time underground
have small, simple eyes that only differentiate
between light and dark.
Snakes that live above ground and need their vision for hunting prey
have very clear vision as well as good depth perception.
Certain species of snakes, such as boas and pythons,
also have what are called’pit organs’ on their heads
which can see heat sources.
So, they essentially have their own pair
of built in infrared goggles.
Number 11, cows.
Cows seem like pretty boring animals,
so you’d expect them to pretty much see the way that we do.
You would be wrong.
This is what cows have tricked you into thinking.
Most cows do see limited colors, since they’re red-green color blind.
They see mostly gray and black, but also versions of yellow and blue,
它们能看到黑色 灰色 还有黄色系和蓝色系
since unlike humans, they only have two color receptions.
Cows also have what is known as’panoramic vision,’
meaning that they can see in all directions
without having to move their heads.
Cows can see 300 degrees just by moving their eyeballs,
which only leaves a small blind spot on the back of their heads.
Good luck trying to sneak up on one of these guys.
Number 10, birds.
Vision is particularly important for birds,
since you don’t want to hit something while you’re 50 feet in the air.
They have the largest eyes relative to their size
in the whole animal kingdom.
Unlike humans, who have three color receptor cones,
allowing us to see red, blue and green, birds have four cones,
能看见红 蓝和绿 而鸟有四个视锥细胞
so they can also see in the ultraviolet spectrum.
That’s pretty handy
because the high phosphorous content in urine glows brightly,
allowing birds like kestrels
to track prey like voles by their urine trails.
Impressively, birds can also rapidly change
the shape of their eye lens,
similar to how a camera functions,
and they have a third, transparent eyelid.
So, some birds of prey can basically see much like a camera
with both a macro lens and a zoom lens,
to focus on multiple things at once.
Particular kind of birds even have their own special eye abilities.
For instance, nocturnal birds such as owls
例如 夜行鸟 比如猫头鹰
actually have tubular eyes rather than spherical ones,
allowing more light to enter the eye for a brighter more crisp image.
This makes it especially handy for night time hunting.
Some sea going birds even have red or yellow oil droplets inside their eyes,
which allows them to see in hazy conditions.
Number nine, horses.
Horses have some of the largest eyes of any land mammal.
Because their eyes are on the sides of their heads,
they have an even greater field of vision than cows,
capable of seeing 350 degrees without moving their head.
Horses see the world in only two colors: blue and green.
This is why in show jumping, where people train horses to jump over obstacles,
the obstacles are always brightly colored,
contrasting heavily with the ground.
A horse would have a hard time distinguishing an obstacle
that was only a few shades different from the ground.
Number eight, frogs.
Frogs are near-sighted, therefore they can’t see at distances that well.
Their eyes are extremely sensitive to movement,
so if a frog’s prey does not move, they will not detect it.
They also have excellent night vision
due to a mirror like layer in the back of their eye called tapetum.
While the extent to which frogs can see colors
has not been determined，
they do have some ability to detect different hues
in the environment around them.
In fact, frogs may even be able to detect color
in extremely low light situations
where other animals only see shades of gray.
Frog eyes are especially interesting to humans,
since they can actually regenerate certain structures
if they’ve been damaged.
Scientists believe that by studying frog’s eyes,
they could discover a cure for certain vision problems in humans.
Frogs also use their eyes to help them swallow food.
After a frog has its prey in its mouth,
you will then see it retract its eyeballs into its head,
actually pushing the food down and lettin’ the frog swallow.
Hopefully, scientists do not research this aspect of frog vision any further,
because that’s really gross.
Number seven, chameleons.
Like birds, chameleons can see all the colors we do,
plus ultraviolet light, which we cannot see.
The most interesting thing about their sight though,
is that a chameleon’s eyes move totally independently from one another.
This means that a chameleon can keep an eye on two things at once,
even if those things are in opposite directions.
Not only can they look in different directions at the same time,
but they can focus their eyes at different levels at the same time,
enabling them to view nearby objects and distant ones
at the same level of focus simultaneously.
Number six, starfish.
For a long time, scientists wondered if starfish could even see at all.
It was known that they have one eye on the end of each arm,
but it wasn’t clear if they could actually see images out of them or not.
Recently, however, scientists have discovered
that starfish can indeed see very basic images-about 200 pixels.
I guess some vision is better than no vision.
What would a starfish need super jacked up eyes for anyway?
Number five, cuttlefish.
The adorably named cuttlefish
has blurrier vision than we do,
and are completely colorblind.
Cuttlefish have one photoreceptor that shows them shades of gray,
and another that detects polarization.
The only time a human will experience polarized light
is when they wear sunglasses
that reduce glare by filtering out an orientation of light waves.
With the help of modified LCD computer monitors,
researchers were able to give us an impression of the changes in polarization
that cuttlefish can see by changing the colors on screen,
like in this image.
Of course this is just a representation for us to understand
just how sensitive cuttlefish eyesight is,
since cuttlefish are actually colorblind.
So, what’s the point of cuttlefish being able to see this?
Well, cuttlefish can also produce polarization patterns on their skin,
which scientists think they may use to communicate,
kind of like signal flags.
Number four, butterflies.
Butterflies see with red, green, blue, UV,
蝴蝶可以看见红光 绿光 蓝光 紫外线
and the wideband light from red to purple.
This really isn’t much, but, like bees,
it does enable them to detect pollen,
and at the end of the day that’s really all they need.
Though they have only 0.04 the visual acuity that we do,
meaning that they can barely see something that’s 50 centimeters away from them,
they can still track down pollen on flowers.
Number three, garden snails.
A snail’s eyes are located at the the tip of their two smallest tentacles.
Because snails can move these tentacles around as they please,
snails have a very wide frame of vision.
If only our eyes were not stuck in our lame skulls,
we could do the same thing.
Garden snails cannot focus or see color,
but they can detect movement and differentiate between different intensities of light.
This allows snails to move towards the sorts of dark places that they like.
Number two, rabbits.
If you’ve ever set a treat down right in front of a rabbit,
only to have it seemingly ignore it, don’t worry,
it’s not trying to tell you that your offering is unwanted,
it probably just can’t see it.
A rabbit’s eyes are so far down its head
that it actually has a blind spot right in front of its nose.
Try moving your treat slightly to the right or the left.
This unique eye positioning also means
that rabbits have very poor depth perception,
since their eyes have little overlap.
Rabbits see objects on their right with their right eye,
and vice versa.
Number one, turtles.
While it is commonly believed that turtles are colorblind,
in reality, they are better at seeing color than we are.
In fact, compared to turtles, we’re the colorblind ones.
Turtles can see one extra color which humans cannot.
The color is referred to as ‘red‘,
though it is ultimately impossible to a human
to picture just what exactly this bonus color is.
Now that you know all these secrets of the animal kingdom,
are you still content with your human eyes?
Do you feel slightly visually inferior like I do?
And, which animal’s vision would you most like to see the world through?
Let me know what you think in the comments section down below.
Thanks for watching!
Humans have a lot of advantages over animals.