How Well Do Dogs See At Night?

Science Daily ^ | 11-8-2007 | University of Wisconsin - Madison.

[blam]

How Well Do Dogs See At Night?

ScienceDaily (Nov. 9, 2007) — A lot better than we do, says Paul Miller, clinical professor of comparative ophthalmology at University of Wisconsin-Madison.

Dogs have good night vision, due in large part to the tapetum, a mirror-like structure which reflects light, giving the retina a second chance to register light that has entered the eye. This is also what makes dogs eyes glow at night. The dog is holding a toy in her mouth. (Credit: Michele Hogan)

“Dogs have evolved to see well in both bright and dim light, whereas humans do best in bright light. No one is quite sure how much better a dog sees in dim light, but I would suspect that dogs are not quite as good as cats,” which can see in light that’s six times dimmer than our lower limit. Dogs, he says, “can probably see in light five times dimmer than a human can see in.”

Dogs have many adaptations for low-light vision, Miller says. A larger pupil lets in more light. The center of the retina has more of the light-sensitive cells (rods), which work better in dim light than the color-detecting cones. The light-sensitive compounds in the retina respond to lower light levels. And the lens is located closer to the retina, making the image on the retina brighter.

But the canine’s biggest advantage is called the tapetum. This mirror-like structure in the back of the eye reflects light, giving the retina a second chance to register light that has entered the eye. “Although the tapetum improves vision in dim light, it also scatters some light, degrading the dog’s vision from the 20:20 that you and I normally see to about 20:80,” Miller says.

The tapetum also causes dog eyes to glow at night.

Adapted from materials provided by University of Wisconsin - Madison.

[Redcloak]

Then how do we explain Hillary?

 

[Spunky]

My poor dog is developing cataracks and not seeing less and less.

[BamaBlue]

She’s a b..ch???

[Spunky]

Oops! seeing less and less.

[blam]

"My poor dog is developing cataracks and seeing less and less."

My oldest one is doing the same.

[freekitty]

I know this doesn’t belong here but all you 50 and 60 boomers you are in for a treat.

It’s Ray Charles, Jerry Lee Lewis and Fats Domino playing the piano together.

http://www.dailymotion.com/video/xe5w0_ray-charles-jerry-lee-lewis

[magslinger]

Goa’uld

[tsmith130]

The tapetum also causes dog eyes to glow at night.

Thank God. It's the only way I can find my chocolate lab in a dark yard at night using a flashlight.

[Redleg Duke]

Same with my Yellow Lab. His eyes glow golden yellow!

[aliquando]

On average men see better at night than women. Women are more sensitive to color than men. It’s all in the rods and cones!!

[Rudder]

In addition to the tapetum lucidum, dogs and cats have all rod vision which means only shades of gray and---easy movement detection. Human beings have a fovea centralis wherein the cones are located for fine detail and color vision.

Question: Turtles have all-cone vision---what for?

[blam]

"I know this doesn’t belong here but all you 50 and 60 boomers you are in for a treat."

Here's a treat.

[acoulterfan]

It’s Ray Charles, Jerry Lee Lewis and Fats Domino playing the piano together.

All I can Say is WOW!!!!!

[Vinnie]

It's the only way I can find my chocolate lab in a dark yard at night using a flashlight.

My black poodle disappears in the shadows also.

PetsMart has a fiber optic-like collar powered by a button battery. Works great.
We have used a lighted arm band available at Lowe's . They have a greenish reflective coating and are battery powered glowing also. Continuous or flashing.
Either are about $10.

[Sacajaweau]

My neighbors little dog has green eyes. The dog looks freaky when the light hits her eyes right. I call the dog “My Little Martian”.

[JustaDumbBlonde]

Is it possible to have a thread on any subject without injecting Hillary ..... please?????

[GregoTX]

[gusopol3]

A lot better than we do

Albert Payson Terhune said the same thing 80 + years ago.

[freekitty]

I haven’t heard that in years. Thank you.

[freekitty]

Out of this world.

[aliquando]

My guess would be species identification. The distinctive marks on turtles are often very subtle but involve color. Just a guess. The do pre-date the dinosaurs and it could be that they pre - date cones.

[rockrr]

Thanks! That was fun!

[Prokopton]

How well do dogs see at night?

It's hard to tell. He's been crying so much lately his eyes are blurry.

[blam]

Here's Jimmy Page playing Dazed And Confused before there was a Led Zeppelin.

Keith Moon told him it would go over like a lead zeppelin.

About a year after Jeff Beck and Eric Clapton left Jimmy page as lead guitar in the group Yardbirds, they changed their name to Led Zepplein and I saw their first US performance at the Filmore west in San Francisco, April, 1969.

Be nice to us old timers, huh? Also, click on my name to see my dogs.

[i_dont_chat]

Jerry Lee Lewis ping

[oldteen]

“Here’s a treat.”

And what it treat it was...thanks for sharing.

[goodnesswins]

THAT was GREAT.....and my husband wonders what I do on FR.....LOL!

[freekitty]

Just a little fun every once in a while. LOL

[Brad's Gramma]

WOW!!!!!!!!!!!!!!!!!!!!

AWESOME!!! Thanks much!

[freekitty]

You are welcome.

[freekitty]

You are welcome.

[freekitty]

I remember The Yardbirds. I remember Led Zeppelin too. Saw him in concert.

Yes, be nice to us oldtimers. We could atleast sing to our songs. LOL

[freekitty]

I love your dogs. They are great.

[Joe 6-pack]

My dog's eyes glow blue, My neck is red, and my niece is black...Diversity at its finest ;-)

[lesser_satan]

That a rough-coat German Shepard?

[Cacique]

ping

[Joe 6-pack]

He was a Hurricane Katrina abandonee that I rescued, so I really don’t know what all courses through his veins. From his behavior and physical characteristics, I personally suspect he’s a GSD/Border Collie mix with a dash of cartoon thrown in for good measure.

[Caramelgal]

On average men see better at night than women. Women are more sensitive to color than men. It’s all in the rods and cones!!

I’ve also heard that women have better depth perception then men, making them naturally better at shooting guns (sharp shooting/target practice) than men. Women are also naturally better at multi-tasking.

So since women are generally more “sensitive” than men; lesson to be learned by men; Never pi$$ off or cheat on a “Second Amendment Sister” – she’s got all the attitude and perception and the fire power to back it up even if you think she’s distracted by her domestic chores.

[blam]

Love it.

[freekitty]

Your family is beautiful. Thanks for sharing.

[Mjaye]

Thanks, that was some extra fine music...

[Joe 6-pack]

"Your family is beautiful..."

I came from a highly dysfunctional family, but they all got better after I left home ;-)

[freekitty]

Me too. LOL

[freekitty]

You are welcome.

[freekitty]

This guy likes Elvis. LOL

[blam]

You Ain't Nothing But A Hound Dog

[freekitty]

I love it.

Does everyone know that Jerry Lee Lewis cousins are Jimmy Swaggart and Mickey Gilley?

[shibumi]

I think it’s time for someone to post “Master of the Obvious.”

[Brad's Gramma]

LOL!!!

That looks AND ACTS like some dawg I know & love.....

:)