1. Human Senses
vs.
Shark Senses,
Fish Senses,
and
Dolphin Senses
Vision, Hearing, and
Smell
By Carrie Whitmore

2. HUMAN SENSES:
VISION:
Has a transparent lens that
focuses light on the retina.
The retina has over a hundred
light receptors that give us the
power to see. Our sharp color
vision comes from a small area
called the blind spot because it The brain combines input of both
interprets raw images our eyes see. eyes into one three-dimensional
Controlled by one-third of the image.
brain. Whenever the brain is Two defects in human vision are
overwhelmed with blindness and color blindness.
emotion/thinking, vision can be In strong light, the iris contracts,
impaired. which reduces the size of the
The human brain receives just aperture which admits light into
about an unlimited amount of the eye. A protective obscure
images in a lifetime. It makes substance reduces the exposure of
decisions on where to place its sensitive light cells.
attention. We can’t always trust
our eyes.

3. HEARING:
The outer ear is shaped like a cup to The inner part of the human ear has
direct sound towards the tympanic a vestibular system that is formed by
membrane. This transmits vibrations three semicircular canals, which are
to the inner ear and goes through just about at right angles to each
many small bones in the middle ear other and are responsible for the
called malleus, incus, and stapes. sense of balance and spatial
The inner ear (cochlea) is a spiral- orientation.
shaped chamber that is internally Finally, the inner ear also has
covered by fiber nerves that react chambers that are filled with a
to vibrations and transmit impulses viscous fluid and small particles
to the brain from the auditory nerve. that contain calcium carbonate.
Our brain combines the input of both Movement of the particles over
ears to figure out the direction and small hair cells in inner ear send
distance of sound. signals to the brain that are
The human ear can perceive interpreted as motion and
frequencies from 16 (very deep bass) acceleration.
and 28,000 (a very high pitch) cycles
per second

4. SMELL:
The nose is the organ that is
responsible for smell.
The cavity is lined with mucous
membranes, which have receptors
that are connected to the
olfactory nerve.
Smells consist of vapors of
various substances.
The smell receptors interact with
the molecules of the smell vapors
and transmit the sensations to the
brain.
The nose also has a structure
Smell receptors of the nose are
called the vomeronasal organ. The
very sensitive to several types of
function of this organ has not been
sensations, such as camphor, musk,
determined yet, but it is thought to
flower, mint, ether, acrid, or
be sensitive to pheromones which
putrid.
influence the reproductive cycle.
The sense of smell can be
temporarily lost when a human has
a cold/is ill.

5. SHARK SENSES:
VISION:
In the majority of shark
species, their eyes are well
developed, large, and have
complex structures.
Some species are able to sense
light and dark through a very thin
section of skin on the top of Focusing in sharks’ eyes is accomplished with
their heads which leads straight the aid of the rectus muscles that pull the
to the pineal gland of their brain. lenses closer to or further away from the
Many sharks who live in shallow retina just as a camera lens focuses.
waters can regulate the amount These muscles, along with the oblique
of light that enters their eyes by muscles control the direction the eye goes in.
dilating or contracting their Due to the poorly lit environment where
pupils in the same manner humans some species live, they lack the ability to stop
do. light from entering their eyes.
Focusing in sharks’ eyes is Most species posses excellent vision in low
accomplished with the aid of the light conditions. The structure in their eyes
rectus muscles that pull the that is responsible for this is called the
lenses closer to or further away tapetum lucidum. Sharks share this ability
from the retina just as a camera with some nocturnal mammals/reptiles that
lens focuses require extreme sensitive vision to survive.

6. HEARING:
It is unclear on whether sharks
can hear the same as humans or
not.
The ears of a shark is
completely internal. They’ are
embedded within the front of the
skull.
Sharks’ ears are responsible for
balance and equilibrium. Their
inner ear has many ducts and sacs
which are known as endolymphatic
ducts.
Around the membranous
labyrinth is more series of fluid Within this area is called the
filled canals (cartilaginous lagena that has been sound en
labyrinth) that are supplied discovered to receive waves in
through the perilymphatic ducts. some fishes.
This protects and supports the Their swaying back and forth
more fragile membranous registers on nearby sensory cells
labyrinth within. that send signals to the brain
The sacculus is a large inner resulting in sensations of
chamber into which the ducts imbalance that the shark then
lead. fixes and corrects.

7. SMELL:
The idea that sharks are able to
smell a drop of blood from a mile
away in the ocean is highly
exaggerated.
Sharks have a pair of nares
(nostril like holes), which are
located just under the edge of
the snout.
Each individual nare is divided by
a nasal flap into two openings. Once sharks pick up a scent
Through these, water is trail, they swims up the through
channeled into the incurrent the trail while moving their heads
aperture and passed over the side to side. As their snout is
lamellae exits. bobbed from side to side through
Dissolved molecules transported the scent trail, the shark is able
along in the water bind to to figure out the direction from
receptor cells that then sends a which the odor is coming from.
signal to the brain (chemosensory Odor detection is not only used
function). in hunting, but sharks also
Sharks’ nares are completely produce pheromones to signal
separate from their mouth and their reproductive state to
throat and do not aid in potential mates. Smell may also
respiration at all. be used in navigation.

8. FISH SENSES:
VISION:
Goldfish have superior vision
compared to humans.
Humans can see red, green, and blue
and can tell light from dark.
Fish, however, can see those three
colors plus ultraviolet light that gives Fish who live in freshwater have no eye-lids that
them polarized vision. It gives them the regulate the amount of light that enters their eyes.
ability to resolve predators/prey through Many species of fish can see in color. This is why
surface of the water without trouble. fishing hooks are made in every single color
This is why goldfish can recognize their imaginable. That way fish don’t get used to one color
owners and know their time of feeding. and stay away from the hook.
Fish eyes are different from human Fishes eyes are located with one on each side of its
eyes. Their lenses are perfectly round head. This allows fish to see on either side of the fish
which allows them to see underwater. at the same time.
However, the location of their eyes creates a blind
spot that is located directly in front of the head.

9. HEARING:
Fish have ears, but they are internal
and don’t have openings.
Sound travels three times faster
through water than the air. Thi s i s w peopl e ar e not supposed
hy
Fish have a hearing range that is equal t o br eak pond i ce w t h a ham er dur i ng
i m
to AM radio. This is not bad, since w nt er .
i
humans can hardly hear underwater. 160 deci bel s w l l dest r oy hum
i an
Their difficult hearing system makes ear s, but i n t he dense w er m l ess
at uch
them vulnerable to profound internal i s needed t o dest r oy t he audi t or y and
and nerve damage when loud noises ner vous syst em of f i sh.
s
occur. Ponder s have r epor t ed i n t he past
t hat l oud l ow frequencies t hat ar e
r epeat ed, l i ke snow pl ow st r ess t hei r
s
f i sh out .

10. SMELL:
Fish are given the ability to smell
through their nostrils called nares. They
are located on the snout of the fish.
Odors that are in the water allow the
fish to locate prey and predators.
However, most fish do not rely on their
sense of smell to feed because what a
fish can smell at a specific time greatly
depends on the strength and direction
of the water current.

11. DOLPHIN SENSES
VISION:
Dolphins have extremely
good vision.
They have binocular vision,
like a human does, but only to
a certain degree.
They can’t see colors really
well. They have the vision of a
severely color-blind person.
However, they don’t need
much color vision, when they
spend 95% of their lives
underwater.
Some of the dolphins
behaviors that are associated
with their vision show high
uses of both sides of their
brain, which is associated
with intelligence.

12. HEARING:
Blindfolded dolphins have
been known to find small
objects in their tanks using
echolocation.
With their echolocation,
dolphins can hear sounds
from tiny objects that are as
far off as 120 yards away.
Dolphins have two hearing
organs. The melon is a big off-
center lump on their
foreheads that allows them
to focus their echolocation Dolphins also have regular
sounds. ears .
Dolphins hearing is one of
the best in the mammalian
world.

13. SMELL:
The smell sense of a
dolphin is not that
complex.
Dolphins may not have
a sense of smell at all.
They don’t have
olfactory lobes in their
brains and olfactory
nerves are missing in all
toothed whales.
This indicates that
dolphins may not have a
sense of smell at all. It
is still not known.

14. BIBLIOGRAPHY - SOURCES
"Animals." Bottle Nose Dolphins. Sea World, 28 Oct 2011. Web. 4 Nov 2011. <http://www.seaworld.org/animal-info/info-
books/bottlenose/senses.htm>.
"Big Puddle." Fish Senses. Word Press, n.d. Web. 1 Nov 2011. <http://phillyrover.wordpress.com/fish-senses/>.
"Dolphin Facts and Information." Dolphin Senses. Dolphins World, 2011. Web. 4 Nov 2011. <http://www.dolphins-
world.com/Dolphin_Senses.html>.
Du Plessis, Amelia. "Sharks." Sharks - Senses. Sharks, 2011. Web. 3 Nov 2011. <http://www.sharks.org.za/senses.html>.
"Elasmodiver." Shark Senses. Elasmodiver, n.d. Web. 2 Dec 2011. <http://elasmodiver.com/shark_senses.htm>.
Nick, . "Fishing Noob." Understanding Fish Senses. Word Press, 15 Nov 2011. Web. 2 Dec 2011. <"Understanding Fish
Seses." Fishing Noob. Word Press, n.d. Web. 1 Nov 2011. . >.
Reilly, Michael. "Discovery Earth." Super Shark Senses. Discovery, n.d. Web. 1 Nov 2011.
<http://dsc.discovery.com/earth/slideshows/shark-senses.html>.
Zamora, Antonio. "Scientific Psychic." Anatomy and Structure of Human Sense Organs. Scientific Psychic, 2004. Web. Oct
29 2011. <http://www.scientificpsychic.com/workbook/chapter2.htm>.

15. BIBLIOGRAPHY - PICTURES
Antonio Zamora. Anatomy and Structure of Human Sense Organs. 2004. Photograph. Scientific Psychic. Web. 10 Nov 2011.
<http://www.scientificpsychic.com/workbook/chapter2.htm>.
Elysia in Wonderland Last. Finding Nemo Wallpaper. 2009. Photograph. Flickr. Web. 10 Nov 2011.
<http://www.flickr.com/photos/figmentsimagination/3236312059/>.
Dolphins. 2008. Photograph. Flickr. Web. 10 Nov 2011. <http://www.flickr.com/photos/20259408@N00/2989054699/>.
Dolphin's Have Names. 2006. Photograph. Natures Corner Magazine. Web. 10 Nov 2011.
<http://www.naturescornermagazine.com/NaturesBlog/archives/2006/05/index.html>.
Fish. 2011. Photograph. Flickr. Web. 10 Nov 2011. <http://www.flickr.com/photos/cubagallery/5591841542/>.
George Probst. Great White Shark Close Up. 2010. Photograph. Flickr. Web. 10 Nov 2011. <http://www.flickr.com/photos/sharkpix/5558629121/>.
How Do Fish... SMELL?. N.d. Photograph. TPWD. Web. 10 Nov 2011. <http://www.tpwd.state.tx.us/kids/wild_things/fish/howdofishsmell.phtml>.
How Dolphin's Echolocate. 2011. Photograph. How Stuff Works. Web. 10 Nov 2011. <http://science.howstuffworks.com/environmental/life/zoology/marine-
life/dolphin-disarm-sea-mine1.htm>.
Marceo Santos. Dolphin. N.d. Photograph. Flickr. Web. 10 Nov 2011. <http://www.flickr.com/photos/manaphy0930/2087329111>.
Nick. Understanding Fish Senses. N.d. Photograph. Fishing Noob. Web. 15 Nov 2011. <http://fishingnoob.com/85/understanding-fish-senses/>.
Norbert Wu. Shark Senses. 2011. Photograph. Flickr. Web. 13 Nov 2011. <http://science.howstuffworks.com/environmental/life/zoology/marine-
life/shark3.htm>.
Shark. 2005. Photograph. Flickr. Web. 10 Nov 2011. <http://www.flickr.com/photos/skymind25/79609238/>.
Shark Senses: Hearing. 2011. Photograph. Flickr. Web. 13 Nov 2011. <http://science.howstuffworks.com/environmental/life/zoology/marine-life/shark-
senses2.htm>.
Sound Generation. N.d. Photograph. UNIVIE. Web. 10 Nov 2011. <http://homepage.univie.ac.at/friedrich.ladich/Topics.htm>.
Vivienne Balonwu. Human Anatomy. 2008. Photograph. Flickr. Web. 10 Nov 2011. <http://www.flickr.com/photos/viviennebalonwu/2706477221/>.