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How can some animals see in the dark?
Human Machine Unit | Lesson 3 of 4
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How can some animals see in the dark?

Human Machine Unit | Lesson 3 of 4
Lesson narration:
English Spanish
Scroll for prep
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DISCUSS:

What do you think is special about nocturnal animal eyes that makes them able to see in the dark? Any ideas?

Hint...

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DISCUSS: Why do you think these animals can see better in the dark than we can?

Eye Comparison

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Slide Image
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nocturnal


1 of 12

active mostly at night

vision


2 of 12

the ability to see
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light


3 of 12

what comes from the Sun and lamps and makes it possible to see things
Slide Image

pupil


4 of 12

the dark opening in the center of the eye
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iris


5 of 12

the colored part of the eye that is shaped like a donut
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model


6 of 12

a pretend version of something that scientists use when the real thing is too big, small, or complicated to work with
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experiment


7 of 12

a test used to discover new information about a question
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retina


8 of 12

the back of the eye that senses light and sends messages to the brain
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structure


9 of 12

the specific form and shape of something

function


10 of 12

what something does
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reflect


11 of 12

when light bounces off something
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dissect


12 of 12

to take something apart to study it
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Image & Video Credits

Mystery Science respects the intellectual property rights of the owners of visual assets. We make every effort to use images and videos under appropriate licenses from the owner or by reaching out to the owner to get explicit permission. If you are the owner of a visual and believe we are using it without permission, please contact us—we will reply promptly and make things right.

Exploration
dilapidated house by Downtowngal , used under CC BY-SA
manhattan by Leifern , used under CC BY-SA
optical illusion by Edgar Mueller , used under CC BY-ND
for rent sign by Bart Everson , used under CC BY-SA
brain by _DJ_ , used under CC BY-SA
flashlight by Stocksnapper
little girl by ANURAK PONGPATIMET
cat dilated pupils by Andreibanc , used under Public Domain
monster flashlight outside by youshoojump
raccoons in cherry tree by AndrewBrownsword , used under CC BY-SA
old woman by beeboys
racoons peaking out by mountainamoeba , used under CC BY
racoons climbing by hobvias sudoneighm , used under CC BY
camping by Zachary Collier , used under CC BY-SA
family by Michael Bentley , used under CC BY-SA
raccoon by Jinterwas , used under CC BY-SA
pizza by The Pizza Review , used under CC BY-SA
cat by ch2daewong
scientist lab computer by Rhoda Baer , used under Public Domain
brains by Prylarer , used under Public Domain
owl by Hector Bottai , used under CC BY-SA
brain background by Simon , used under Public Domain
deer by harrystilianou002
little girl sleeping by Petra , used under Public Domain
sheep brain by Aaron Bornstein , used under CC BY-SA
surgery by skeeze , used under Public Domain
gears by Libertad , used under Public Domain
lightbulb by Greg Westfall , used under CC BY-SA
eyeballs by Patrick J. Lynch , used under CC BY-SA
eyeballs connected to brain by Pete Linforth , used under Public Domain
ambulance by Canuckle , used under CC BY-SA
green eye by Pedramiri , used under CC BY-SA
business cards by Niek Verlaan , used under Public Domain
iPhone by Hurk , used under Public Domain
nervous system by Chris , used under CC BY-SA
old photograph by Michal Jarmoluk , used under Public Domain
Inside Out by Disney / "fair use" ??
light switch by Martin Cathrae , used under CC BY-SA
door by r. nial bradshaw , used under CC BY
cat's eyes by Takuma Kimura , used under CC BY-SA
owl's eyes by Airwolfhound , used under CC BY-SA
rodents eyes by Arjan Haverkamp , used under CC BY-SA
night sky by Hector Bayes M , used under CC BY-SA
moon by lovecatz , used under CC BY-SA
tarsier by JennyHuang , used under CC BY-SA
tarsier in tree by David Evison
gecko by Megan
Crested Gecko pupil response by JB's Cresties
dog in the dark by Rennett Stowe , used under CC BY-SA
deer at night by lovecatz , used under CC BY-SA
cow at night by Clark
cow eye dissection by Project NEURON , used under CC BY
making tape glow on bike by Hyper Spectrum Reflective
masking tape by TapeCase
making tape glow video by Steve Cole
cat by Andrew Gatt , used under CC BY
dog by Thirteen of Clubs , used under CC BY-SA
crocodile by sodai gomi , used under CC BY
face in dark by Natalie 93
photographer by fedi
red-eye effect humans by PeterPan23
red eyes by Mikael Häggström
Activity
racoons by USFWS Mountain-Prarie , used under CC BY
first face by Konstantin Chagin
second face by pathdoc
pupil response by Hasan Sawan
two lizards by Ltshears , used under CC BY-SA
graphic pencil by JohannPoufPouf , used under Public Domain
Other
Unit: black cat, green eyes by LisaRedfern
Credits

Featured Reviews

“We loved the suspenseful story leading up to the mystery of how animals see in the dark. It was a great extended lesson to the previous human eye experiment. It was fun to see how a smaller pupil made a sharper image. Students loved the discovery process. ”
· · Teacher
“The kids loved seeing pupils grow and shrink in response to light. This activity was a great follow-up to our cow dissection. The kids had seen the tapetum in the dissection, and we had discussed its purpose, but seeing it in action in this lesson made it real for them.”
· Suzanne · Teacher
“The kids' reactions when they saw each other's pupils get smaller, and again when they pulled the pupil card out of their model! They couldn't stop talking about their eyes as they went out to lunch!”
· Courtney · Teacher
“The video at the end showing the nocturnal animals' pupils grow!”
· · Teacher
“I love the step by step Doug describes so everyone is on track, fabulous lesson! ”
· Sandy · Teacher
“We loved how the eye lenses experiment worked in both Mystery 2 and 3. ”
· Jeanne · Teacher
“The kids were fascinated and excited to participate. They loved the lizard pupils and discovering how the large pupil let in more light in the activity. Great lesson! A+++”
· Ginny · Teacher
“My students loved this lesson! It is so exciting as a teacher to watch my students get so excited about learning!”
· Laura · Teacher
“We really liked this lesson. Even I learned about the different colors in the back of the night-vision eyes. The change in pupil size experiment was cool, too.”
· Leonard · Homeschooler
“I was so impressed by how many kids were able to figure out why the pupil changes and make good predictions about why eyes glow. ”
· Megan · Teacher
“The videos did a great job of showing the action of the pupil!”
· Kimberly · Teacher
“We loved using the eye model to show what happens when our pupils contract - what a great visual aid!”
· Samantha · Homeschooler
“The students had some a-ha moments when they pulled out the smaller pupil card. Students were looking at everyone's eyes all day to see what size their pupils were.”
· Glenda · Admin
“From the materials share at the beginning of the lesson, students were able to come to their own, correct, conclusions about how some animals see in the dark and why humans have more difficulty with this. Great inquiry learning.”
· Mary · Teacher
“This lesson kept my kids talking throughout the day. How cool is it that your pupil shrinks and widens depending on the light!”
· Tricia · Teacher
“AWESOME!! The kids really liked this lesson and how they can see in the dark.”
· Jenn · Teacher
“One of my favorite lessons so far!”
· Shauna · Teacher
“My students loved the activity with the pupils. We turned out the lights and I closed my eyes while they counted. The light went on, I opened my eyes and they started screaming. My pupils must have really contracted quickly!! It was great!!”
· Barbara · Teacher
“The kids LOVED learning about why eyes show up different colors in photographs.”
· David · Teacher
“My kids loved the eye activities! Their favorite part was watching the pupils shrink after the 20 second count down. The Body mysteries have been some of my students' favorite!”
· Abbie · Teacher
“We loved learning how our cats can see in the dark, and the pupil experiment worked really well to illustrate the lesson.”
· Melissa · Homeschooler
“We have observed pupil dilation before, but this was a fun variation on it, and much more informative. Thank you for another great lesson. ”
· Josie · Homeschooler
“This lesson really lends itself to rich scientific discussion. In most of the Mysteries the Activity is usually the best part, but the discussion that this lesson generates is some of the best I have ever had in my classroom. We even started talking about that weird "red-eye flash" flash that happens with some cameras. Because of this lesson students were able to conclude that the rapid orange flash was probably designed to close your pupil enough to reduce red-eye. Very cool.”
· · Teacher
“The details of having an "eyeball" and "watcher" student for the experiment worked very well. Students were very excited to see the results of this experiment!”
· Kim · Teacher
“Students loved all parts of the lesson, especially the covering the eye and watching iris get smaller when lights were turned on after 20 seconds.”
· Geri · Teacher
“When my class started this mystery, we had a lot of misconceptions about animals and how they would see a t night. They loved the part when we discovered the reason for their pets having a certain color of eyes when light flashes across them. What a great mystery! ”
· Brandi · Teacher
Lesson narration:
English Spanish

Grade 4

Human Body, Vision, & The Brain

Structure & Function of Eyes

4-PS4-2, 4-LS1-1

Activity Prep

Print Prep
In this lesson, students delve further into the workings of the eye, exploring the function of their iris and pupil. In the activity, Pupil Card, students add a smaller pupil to the eye model that they created in the previous lesson. Then they observe how the changing size of the pupil controls how much light enters the eye.
Preview activity

I have a Mystery Pack

Pupil Card printout Print 30 copies
Eye Model from Previous Lesson
Students need the eye models that they created in the previous Lesson.
Details
30
Markers
Students should use the same color that they used to color the iris in Lesson 2. Crayons or colored pencils also work.
Details
30 markers
Scissors
30 pairs
Prep Instructions

We suggest students work in pairs. Students need the complete eye model (magnifying lens and the index card “retina”) that they made in the previous lesson. If any students were absent for this activity, you can pair them with someone who has an eye model. Homeschool students can work on their own, but will need a partner for some parts of the activity.

Watch This Quick Video

In the first activity, students will experiment to see how their eyes change in response to changes in the light around them. Watch this video to see the change they are looking for. (You can also watch for this change in your own eyes. Look at your eyes in a mirror in a dark room and watch what happens when you turn on the lights.)

Exploration

7 mins

Hands-On Activity

30 mins

Wrap-Up

8 mins

Grade 4

Human Body, Vision, & The Brain

Structure & Function of Eyes

4-PS4-2, 4-LS1-1

Slow internet or video problems?
Credits
 
Body Lesson 3: How can some animals see in the dark?

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