How do dogs "see" with their noses? - Alexandra Horowitz
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0:07 - 0:08"Hi, Bob."
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0:08 - 0:11"Morning, Kelly. The tulips looks great."
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0:11 - 0:15Have you ever wondered
how your dog experiences the world? -
0:15 - 0:17Here's what she sees.
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0:17 - 0:19Not terribly interesting.
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0:19 - 0:22But what she smells,
that's a totally different story. -
0:22 - 0:25And it begins at her wonderfully
developed nose. -
0:25 - 0:28As your dog catches
the first hints of fresh air, -
0:28 - 0:35her nose's moist, spongy outside helps
capture any scents the breeze carries. -
0:35 - 0:37The ability to smell
separately with each nostril, -
0:37 - 0:39smelling in stereo,
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0:39 - 0:42helps to determine the direction
of the smell's source -
0:42 - 0:44so that within the first
few moments of sniffing, -
0:44 - 0:48the dog starts to become aware of not
just what kind of things are out there -
0:48 - 0:51but also where they're located.
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0:51 - 0:52As air enters the nose,
-
0:52 - 0:56a small fold of tissue
divides it into two separate folds, -
0:56 - 0:59one for breathing
and one just for smelling. -
0:59 - 1:01This second airflow enters a region
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1:01 - 1:04filled with highly specialized
olfactory receptor cells, -
1:04 - 1:09several hundred millions of them,
compaired to our five million. -
1:09 - 1:12And unlike our clumsy way of breathing
in and out through the same passage, -
1:12 - 1:15dogs exhale through slits
at the side of their nose, -
1:15 - 1:19creating swirls of air that help
draw in new odor molecules -
1:19 - 1:24and allow odor concentration to build up
over mulitple sniffs. -
1:24 - 1:28But all that impressive nasal architecture
wouldn't be much help -
1:28 - 1:33without something to process the loads
of information the nose scoops up. -
1:33 - 1:37And it turns out that the olfactory system
dedicated to proessing smells -
1:37 - 1:43takes up many times more relative
brain area in dogs than in humans. -
1:43 - 1:44All of this allows dogs to distinguish
-
1:44 - 1:48and remember a staggering
variety of specific scents -
1:48 - 1:53at concentrations up to 100 million times
less than what our noses can detect. -
1:53 - 1:56If you can smell a spritz of perfume
in a small room, -
1:56 - 2:00a dog would have no trouble smelling it
in an enclosed stadium -
2:00 - 2:03and distinguishing its ingredients,
to boot. -
2:03 - 2:06And everything in the street,
every passing person or car, -
2:06 - 2:08any contents of the neighbor's trash,
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2:08 - 2:10each type of tree,
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2:10 - 2:12and all the birds and insects in it
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2:12 - 2:16has a distinct odor profile telling
your dog what it is, where it is, -
2:16 - 2:19and which direction it's moving in.
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2:19 - 2:21Besides being much
more powerful than ours, -
2:21 - 2:26a dog's sense of smell can pick up things
that can't even be seen at all. -
2:26 - 2:28A whole separate olfactory system,
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2:28 - 2:32called the vomeronasal organ,
above the roof of the mouth, -
2:32 - 2:36detects the hormones all animals,
Including humans, naturally release. -
2:36 - 2:38It lets dogs identify potential mates,
-
2:38 - 2:42or distinguish between friendly
and hostile animals. -
2:42 - 2:44It alerts them to our various
emotional states, -
2:44 - 2:48and it can even tell them
when someone is pregnant or sick. -
2:48 - 2:51Because olfaction is more primal
than other senses, -
2:51 - 2:54bypassing the thalamus to connect
directly to the brain structures -
2:54 - 2:57involving emotion and instinct,
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2:57 - 3:02we might even say a dog's perception
is more immediate and visceral than ours. -
3:02 - 3:04But the most amazing thing about
your dog's nose -
3:04 - 3:06is that it can traverse time.
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3:06 - 3:09The past appears in tracks
left by passersby, -
3:09 - 3:12and by the warmth
of a recently parked car -
3:12 - 3:17where the residue of where you've been
and what you've done recently. -
3:17 - 3:19Landmarks like fire hydrants and trees
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3:19 - 3:22are aromatic bulletin boards
carrying messages of who's been by, -
3:22 - 3:23what they've been eating,
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3:23 - 3:25and how they're feeling.
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3:25 - 3:27And the future is in the breeze,
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3:27 - 3:31alerting them to something or someone
approaching long before you see them. -
3:31 - 3:34Where we see and hear something
at a single moment, -
3:34 - 3:38a dog smells an entire story
from start to finish. -
3:38 - 3:41In some of the best examples
of canine-human collaboration, -
3:41 - 3:44dogs help us by sharing
and reacting to those stories. -
3:44 - 3:47They can respond with kindness
to people in distress, -
3:47 - 3:49or with aggression to threats
-
3:49 - 3:52because stress and anger
manifest as a cloud of hormones -
3:52 - 3:55recognizable to the dog's nose.
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3:55 - 3:56With the proper training,
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3:56 - 3:58they can even alert us
to invisible threats -
3:58 - 4:01ranging from bombs to cancer.
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4:01 - 4:03As it turns out, humanity's best friend
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4:03 - 4:07is not one who experiences
the same things we do, -
4:07 - 4:12but one whose incredible nose reveals
a whole other world beyond our eyes.
- Title:
- How do dogs "see" with their noses? - Alexandra Horowitz
- Speaker:
- Alexandra Horowitz
- Description:
-
View full lesson: http://ed.ted.com/lessons/how-do-dogs-see-with-their-noses-alexandra-horowitz
You may have heard the expression that dogs ‘see with their noses.’ But these creature’s amazing nasal architecture actually reveals a whole world beyond what we can see. Alexandra Horowitz illustrates how the dog’s nose can smell the past, the future and even things that can’t be seen at all.
Lesson by Alexandra Horowitz, animation by Província Studio.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TED-Ed
- Duration:
- 04:28
Jessica Ruby edited English subtitles for How do dogs "see" with their noses? - Alexandra Horowitz | ||
Jessica Ruby approved English subtitles for How do dogs "see" with their noses? - Alexandra Horowitz | ||
Jessica Ruby edited English subtitles for How do dogs "see" with their noses? - Alexandra Horowitz | ||
Jessica Ruby accepted English subtitles for How do dogs "see" with their noses? - Alexandra Horowitz | ||
Jessica Ruby edited English subtitles for How do dogs "see" with their noses? - Alexandra Horowitz | ||
Jessica Ruby edited English subtitles for How do dogs "see" with their noses? - Alexandra Horowitz | ||
Jennifer Cody edited English subtitles for How do dogs "see" with their noses? - Alexandra Horowitz | ||
Jennifer Cody edited English subtitles for How do dogs "see" with their noses? - Alexandra Horowitz |