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  • How do Clouds Float?

    Created: 11/30/2017      Updated: 12/5/2017

    In this series, we'll be addressing some common questions from visitors and readers. Do you have a science question that has you stumped? Ask our museum scientists via our form here and we'll answer it on our blog!

    Today's Question:

    How do clouds float?

    Clouds are made of water. Water is denser than air. Water doesn't float in the air. Therefore, clouds can't exist.

    Clearly, that’s not true. Clouds do exist, and they do float in the air. How? Why do clouds form? Do clouds fall to the ground? Why do clouds sometimes disappear?

    Clouds are created from water vapor that condenses into water droplets, and warm air and water vapor will rise above the cold air around it1. Your breath on a chilly winter day or the steam from a tea kettle are examples of water vapor that rises. Are clouds warmer than the surrounding air, and if so, what makes clouds warm?

    Clouds form when the sun creates warm, moist air by heating and evaporating water on the earth’s surface. The warm, moist air is less dense than the cold air above it, so that warm air rises2. The warm air cools as it comes into contact with the cooler air above. Cold air cannot hold as much moisture as warm air: the vapor has to condense into a liquid. This is the beginning of a cloud.

    The sun heats the earth, and causes water on the ground to evaporate3. The water rises, cools, and condenses. A cloud is formed!

    Clouds form when warm wet air rises and condenses in cold air. This explains why clouds exist, but now how do clouds stay in the air? Once the cloud forms in the cold air, why doesn't the cloud cool down and sink back to the ground?

    There are several reasons clouds float: first, the droplets in a cloud are small. Very small. An average water droplet in a cloud may only be 20 micrometers across4. That is half as wide as a typical human hair, and about the same size across as a particle of dust5. Even though dust is heavier than the air around it, a dust particle is so small that it can float in the air for a long time before falling. Water droplets in air behave the same way as dust6.

    The second reason that clouds can float in the air is that there is a constant flow of warm air rising to meet the cloud: the warm air pushes up on the cloud and keeps it afloat.

    Third, clouds stay warmer than the air around them because they absorb the sun’s energy better than the surrounding air7.

    Clouds don't float forever—if the surrounding air warms up, then the air is able to contain the cloud's moisture as vapor, and the cloud will disappear. And sometimes, the cloud becomes so large and moist that the water droplets in the cloud begin sticking to each other, and grow bigger and bigger. The water droplets become so big that they no longer behave like dust particles. The droplets begin to fall. If you look up at this kind of cloud, your face will be wet: those droplets are now called "rain" and you really ought to go inside.

    This map shows how much cloud has fallen to the ground in 2017. More green means more rain8.

    Kyle Schiber
    Nature Museum Volunteer

    [1] Khan, Sal. "Ideal Gas Equation: PV=nRT" Khan Academy. 2017. Retrieved November 27, 2017 from

    [2] NC State University Climate Education for K-12. “How Clouds Form”. (August 13, 2013). Retrieved November 27, 2017, from

    [3] Precipitation Measurement Missions, NASA. “The Water Cycle” diagram by NOAA National Weather Service Jetstream. (June 8, 2011). Retrieved November 27, 2017, from

    [4] Space Math, NASA S’COOL Team. “Cloud Droplets and Rain Drops”. Retrieved November 27, 2017, from

    [5] Engineering Toolbox. “Particle Sizes”. Retrieved November 27, 2017, from

    [6] Scientific American. “Why do clouds float when they have tons of water in them?” (May 31, 1999). Retrieved November 27, 2017, from

    [7] My NASA Data. “Measuring the Temperature of the Sky and Clouds”. (2017). Retrieved November 27, 2017, from

    [8] National Temperature and Precipitation Maps, NOAA. “Total Precipitation, January-October 2017, CONUS”. Retrieved November 27, 2017, from[]=prcp-total#us-maps-select

    Do you have a science question that has you stumped? Ask our museum scientists via our form here and we'll answer it on our blog!

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  • Our Gratitude for Nature’s Connection

    Created: 11/21/2017      Updated: 11/22/2017

    I’m never more grateful for the gifts of nature than during the approach to the Thanksgiving holiday.

    Our Midwest Thanksgivings are accentuated by the profound season change to autumn, featuring abundant harvests, wildlife preparing for winter and leaves changing color then dropping along with the temperature. The holiday brings our relationships into focus through nature’s lens and through family gatherings.

    Anticipating family time and pausing to express gratitude for one another and our blessings affirms our feelings of connectedness. In our family, it also affirms a connection to nature. Even with our children now all adults, our family gatherings and adventures usually find us outdoors in nature -- playing, exploring, watching, reflecting, or running in a Turkey Trot. It just feels good to be outdoors.

    Our Thanksgiving celebration and meal is generally followed by a stroll outdoors, much as we did when I was growing up in Chicago’s west side where my police officer father connected to nature through his garden. He loved growing and harvesting the vegetables, and faithfully prepared the soil for its dormant, winter rest. He did so with appreciation and anticipation of spring planting.    

    Wherever you spend the holiday, a nature connection is not far away. Take a stroll outdoors. You may be rewarded by hearing the distinctive trill of sandhill cranes on their migration south. This week is expected to be the peak time for these large, highflyers to pass over Chicago. Many other birds, such as robins, are gathering in groups in preparation to migrate or are busy eating as many berries as seeds as possible to “bulk up” for winter.

    Notice nature. For example, watch squirrels scurrying around lawns and parks, busily stocking up on fallen seeds and nuts. Pause to notice the trees in your neighborhood. Most are nearly leafless and reveal the tangles of branches and limbs reaching skyward. Watch and listen with appreciation for nature’s stories.

    Like the connections we foster with our family and friends by spending time together, our connection to nature grows stronger through the time we spend in it.

    May you and your family deepen your connections and share in the abundance of nature’s gifts that we gratefully share. Happy Thanksgiving.  

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  • Spooky Science II: Chicago Academy of Sciences-inspired Halloween costumes

    Created: 10/25/2017      Updated: 10/25/2017

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    Halloween is less than a week away, but if you still don’t have a costume ready to go, don’t worry. We have even more scientifically-focused suggestions that date back to the early days of the Chicago Academy of Sciences! Click here to check out our first list of pioneering explorers and scientists, or read on for even more Halloween costume inspiration!

    Anna Pederson Kummer

    Anna Pederson Kummer

    Love plants? Anna Pederson Kummer's for you! She was a Chicago Academy of Sciences curator in the 1940s, as well as a botanist. Here's what you need to assemble the look:

    • A plaid vintage-style dress (long-sleeve, with the skirt hitting mid-calf)
    • Low- or kitten-heel shoes
    • 1940s-inspired hair (think lots of rolls with bobby pins and combs to keep them in place)

    Top it all off with a collection of pressed plant sheets or scientific plant illustrations. Kummer specialized in weed seedlings. Click here to check out a weed seedling leaflet published by the Academy and written by Kummer in 1942.

    Dr. William Beecher

    Dr. William Beecher

    In addition to being one of our beloved former directors, Dr. William Beecher was a noted ornithologist. Get his 1960s look by grabbing the following:

    • A gray suit
    • White dress shirt
    • Black tie
    • Thick, dark-framed glasses
    • Binoculars

    Find a plush bird or two and you'll have the complete look! Did you know that our Beecher Lab is named after Dr. Beecher? Learn about Dr. Beecher's legacy from students who studied with him here and here.

    Leonora K. Gloyd

    Leonora Gloyd

    Her husband Howard was Academy Director for several years, but Leonora was a noted Academy explorer in her own right (and we've got the photo to prove it!). To get her look, grab the following:

    • A Panama or asymmetrical sunhat
    • A loose-fitting safari or cargo vest
    • A white oxford shirt
    • Tall hiking boots and boot socks
    • Riding breeches (or similar pants)

    Grab a butterfly net and you're all set! While Howard was a herpetologist and specialized in reptiles and amphibians, Leonora was an odonatist and specialized in damselflies and dragonflies. There's even a damselfly named after her! Click here to read an Academy-published bulletin written by Leonora herself.

    Edwin & Roy Komarek

    Edwin and Roy Komarek

    These explorer brothers were mammalogists and curators who worked for the Academy in the 1930s and 1940s, and often accompanied the Gloyds on expedition out west. To get Edwin's look, find the following:

    • A patterned fleece pullover
    • Dark jeans
    • Tall hiking boots
    • Round-frame glasses
    • An old-fashioned motion picture camera

    To get Roy's look, grab:

    • Octagonal glasses
    • A Panama or safari hat
    • A button-down utility shirt
    • Khaki pants
    • Tall boots
    • A pipe

    Whether you choose Edwin or Roy, be sure to grab a plush furry critter or animal pelt to complete the look. To read about the brothers' work on expedition, check out this Academy-published bulletin from 1938.

    Planning on using one of the other looks for your costume this year? Be sure to share it with us on Twitter, Facebook or Instagram! We'd love to see it!

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  • How do Cicadas Make Sound?

    Created: 8/25/2017      Updated: 8/25/2017

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    In this series, we'll be addressing some common questions from visitors and readers. Do you have a science question that has you stumped? Ask our museum scientists via our form here and we'll answer it on our blog!

    Today's Question:

    How do cicadas make sound?

    …and how are they so loud? Cicadas are the song of summer across the United States, Chicago included. Even just two miles from downtown the droning of cicadas in trees can be downright overwhelming in July and August afternoons. But cicadas are so small: how do they make such a powerful sound? With no vocal chords, no lungs, and no subwoofer it ought to be impossible to hear a cicada from a mile away and yet, it's not. The loudest cicadas can emit a sound at over 100 decibels[1], which can be heard over a mile and a half away.[2]

    If you suspect that cicadas make sound the same way that the cricket, that other noisy summer insect, does then you'd get points for effort, but no points for being correct. Crickets make sound by rubbing their wings together (not its legs!), and cicadas have a special organ called a tymbal that produces sound. The tymbal contains a series of ribs that buckle one after the other when the cicada flexes its muscles. Every time a rib buckles, the rib produces a click.[3] Many clicks produce a buzzing sound. The action is like how a bendy straw makes sound: pulling and pushing the ribs of the bendy straw together makes a series of clicks. If you could push, pull, and twist a bendy straw hundreds of times a second the sound of the clicks would be so close together that you'd only hear a buzzing sound: this is how fast the cicada is able to vibrate its tymbal.

    Chicagoans can hear several different species of cicada in the summer: the dog-day cicada, the Linne's cicada and the scissor-grinder cicada are all common.[4] In fact, the author heard all three of these cicada calls through his window while writing this post. Click on the links above to hear the sound for each cicada and to learn more about each of these species.

    Scissor-grinder cicada resting on a Chicago sidewalk

    Scissor-grinder cicada resting on a Chicago sidewalk. Photo by author.

    And yes, some online sources will tell you that it's possible for a cicada to damage your hearing. This is technically true and at the same time, there’s no reason to worry. The very loudest cicada, at 108 decibels[1], would permanently damage your hearing if you held it up to your ear for two minutes straight.[5] Chicago cicadas are not even close to being that loud. Even if we estimate them at 90 decibels, as loud as a motorcycle from 25 feet away, it would take 8 hours of continuous play time for it to damage your hearing. Cicadas are completely, absolutely harmless. Just loud. Very loud.


    Kyle Schiber
    Nature Museum Volunteer


    [1] Fleming, Nic. “The Loudest Insect in the World”. (2014, October 3). Retrieved August 8, 2017, from 

    [2] Wolfram Alpha LLC. 2017. Wolfram|Alpha. Retrieved August 9, 2017 from

    [3] Young, D., and Bennet-Clark, H. C. “The Role of the Tymbal in Cicada Sound Production”. (1994, December 19). Retrieved August 7, 2017 from

    [4] The Song of Insects. 2017. Retrieved August 13, 2017 from

    [5] IAC Acoustics. “Comparative Examples of Noise Levels”. 2017. Retrieved August 8, 2017, from

    Do you have a science question that has you stumped? Ask our museum scientists via our form here and we'll answer it on our blog!

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  • Priority Species Update: A Museum Full of Smooth Greensnakes

    Created: 8/22/2017      Updated: 8/22/2017

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    Allison Sacerdote-Velat holding an adult Smooth Greensnake

    Curator of Herpetology Allison Sacerdote-Velat has spent much of her summer working with one of our priority species - the Smooth Greensnake. Allison and her team have been surveying for Smooth Greensnakes in sites in several counties in Illinois, but took a break to give us a quick update on teh work they've done so far and the work that's still ahead.

    We have been surveying for Smooth Greensnakes in sites in Lake, DuPage, Cook, DeKalb, and Grundy Counties. Some sites are part of a long-term population monitoring study and some are previous release sites for headstarted snakes.

    Smooth Greensnake hatchlings emerging from eggs

    When we headstart Smooth Greensnakes, we can focus on improving two aspects of their survival; hatching success of eggs and hatchling overwintering survival. In DuPage County, we are improving hatching success by incubating half of the eggs from nests that we find in the field at our Forest Preserve District of DuPage County's partner facility, Willowbrook Wildlife Center. Once the eggs hatch, we measure, mark, and release the hatchlings back to their nest sites. By individually marking hatchlings, we hope to find them again next season to improve estimates of hatchling overwintering survival.

    Tiny Smooth Greensnake hatchling held by Allison Sacerdote-Velat

    Meanwhile, we monitor the fates of the remaining eggs in the field to determine wild hatching rates. In partnership with Lake County Forest Preserve District, we are using the second headstarting strategy, improving both hatching success and hatchling survival by caring for the hatchling Smooth Greensnakes until next summer. We aim to improve their chances of surviving that critical first year, by keeping them safe from predators until they are larger, and increasing their body size so they are better able to survive winter and produce more young once they are released.

    Smooth Greensnake hatchlings in the Nature Museum lab

    This season, we have incubated, hatched, marked, and released snakes from 75 eggs in DuPage County, and we are currently headstarting 81 hatchlings from Lake County at Peggy Notebaert Nature Museum.  

    Allison Sacerdote-Velat
    Curator of Herpetology

    Want to learn more about this project? Be sure to follow us on Twitter as we share Allison's updates from the field!

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  • What is the Fastest Turtle?

    Created: 6/21/2017      Updated: 6/21/2017

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    In this series, we'll be addressing some common questions from visitors and readers. Do you have a science question that has you stumped? Ask our museum scientists via our form here and we'll answer it on our blog!

    Today's Question:

    What is the fastest turtle?

    Turtles: they're not renowned for their speed. Sure, the turtle** wins in The Tortoise and the Hare, but just to serve as a humiliating example of arrogance. No one celebrates for the tortoise in that story, you know? It's ok, though. Turtles don't mind! There's no need to be fast when you carry your own armor for defense and your food is stationary.

    But surely there is at least one turtle that's massively mobile. A turtle with wheels. A turbo turtle. Which turtle is it? Can any turtle outrun a human? What is the fastest a turtle can go?

    We begin with the official recordkeepers. The Guinness Book of World Records maintains the record for fastest tortoise: the tortoise ran at an average speed of 0.63 miles per hour.[1] Tortoises are notoriously slow, however, even for turtles. We can do better.

    Some turtles can "sprint" much faster than any tortoise. Compare the Guinness World Record tortoise video[2] against any number of Youtube "fastest turtle" videos to see soft-shelled turtles rushing to safety (gee, what incentive would a soft-shelled turtle have to be able to move quickly?). From one of these "fastest turtle" videos, I estimated the speed of a sprinting turtle based on the distance it ran (about 15 feet), divided by the time it took to move that distance (about 3 seconds). From that quick calculation, soft-shelled turtles can move at a speed of 3 miles per hour. For comparison, that's a comfortable walking pace for an adult human.

    That's not the fastest turtle, though: turtles swim much faster than they can walk, and the blog post's question didn't specify how the fastest turtle was getting around. The leatherback sea turtle is reported as being able to swim up to 22 miles per hour, though I could not find an original source for that claim.[3]

    We're not done yet: turtles have moved at least 1,000 times faster than even the fastest sea turtle.

    Animals have been launched into space many times to test the effects of space on living things.[4] Turtles have had their share of space flights: turtles have been sent into low-earth orbit by Soviet (Soyuz 20) and Iranian (Kavoshgar-3) space missions. All turtles survived both missions. To maintain low-earth orbit, the turtles traveled at 17,000 miles per hour.[5] 

    But the fastest turtles ever, and the ones who have been farthest from earth, are two Russian tortoises that were launched aboard the Zond 5 spacecraft in 1968. This spacecraft traveled to the moon (it didn't land, of course: humans are the only animal that has stepped onto the moon) and returned safely to earth. Details about the speed of this flight are difficult to find.

    Proton-K rocket

    This Proton-K rocket launched the Zond spacecraft. Not pictured: two intrepid tortoises.[6]

    However, NASA used a similar flight plan during the Apollo missions, and those flights reached speeds of 23,000 miles per hour.[7] It is fair to conclude that the Zond 5 spacecraft and those two Russian tortoises reached a similar speed! Leatherback turtles travel over 10,000 miles during their migrations.[8] If a leatherback turtle could swim its maximum speed without stopping, it would complete that trip in 19 days. A rocket-propelled turtle covers that distance in 25 minutes.

    And that, without a doubt, is the fastest a turtle has ever traveled.

    The complete turtle velocity leaderboard:


    Turtle (method of locomotion)

    Maximum Speed (mph)


    Bernie, The fastest tortoise according to Guinness World Records (ambling)



    Soft-shelled turtle (moving/walking quickly)



    Leatherback turtle (swimming)



    Turtle (spacecraft in low earth orbit)



    Russian Tortoise (spacecraft in circumlunar orbit)



    **Remember: all tortoises are turtles. Not all turtles are tortoises. 

    Kyle Schiber
    Nature Museum Volunteer

    [1] Swatman, Rachel. “Record Holder Profile Video: Bertie the fastest tortoise”. (2015, September 9). Retrieved June 8, 2017, from

    [2] Fastest Tortoise – Guinness World Records. Video published by Guinness World Records. (2015, September 9). Retrieved June 8, 2017, from

    [3] Shweky, Rachel. “Speed of a Turtle or Tortoise”. (1999). Retrieved June 9, 2017, from

    [4] Animals in space. (2017, May 26). In Wikipedia, The Free Encyclopedia. Retrieved June 11, 2017, from

    [5] Orbital speed. (2017, June 9). In Wikipedia, The Free Encyclopedia. Retrieved June 11, 2017, from

    [6] Space Launch Report: Proton Data Sheet. (2017). Retrieved June 10, 2017 from

    [7] Translunar Injection. NASA, archived by (2016, December 4). Retrieved June 9, 2017 from

    [8] Sea Turtle Migration.

    Do you have a science question that has you stumped? Ask our museum scientists via our form here and we'll answer it on our blog!

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  • Statement from Nature Museum President & CEO Deborah Lahey

    Created: 6/13/2017      Updated: 6/16/2017

    Statement by Deborah Lahey, President and CEO of the Chicago Academy of Sciences/Peggy Notebaert Nature Museum regarding the United States announcement to withdraw from the Paris Climate Agreement.

    There is an undeniable correlation between the health of our planet and the health of all living things. That fact is what makes the United States’ announcement withdrawing from the Paris Climate Agreement a concern to many people. The action could erode the collective, global efforts needed to provide solutions to climate change as well as other collaborations. Our world needs every leading country working together for the good of all living things.

    The Chicago Academy of Sciences / Peggy Notebaert Nature Museum is deeply committed to fact-based, environmental research and education, and we advocate for uniting global and local efforts to protect our planet and nature. Through our collection and ongoing research, we have documented 160 years of history of the environmental changes in our region and continue to contribute to science-based learning.

    On a more personal and individual level, the Nature Museum is building a deeper connection between nature and the public. Every day, we provide a welcoming gateway for people to better understand our urban environment and what it means to them. Through engaging exhibit experiences and programs, including the self-produced exhibit Our House: Rethinking Home in a Changing Climate, people are encouraged to think about how our choices -- from building homes to driving cars – can be in harmony with nature, or not.

    Our region is fortunate that Chicago Mayor Rahm Emanuel announced in response to the U.S. decision that the City of Chicago will continue forward “to achieve goals set in the Paris deal.”  Many regional business and civic leaders also are publicly stating their support for the country to stay in the agreement. This leadership will help Chicago to continue making progress reducing carbon emissions in line with the international climate accord.

    We believe it is critical for everyone to stay informed and united in efforts to address climate change. To increase our contributions to these efforts, the Nature Museum plans to convene more forums with organizations, policy officials, municipalities, thought leaders, and individuals to dialogue about reducing greenhouse gas emissions and pursuing innovative clean energy sources that are good for the environment and create new jobs.

    Be assured that our teams of scientists and educators are working to build greater public understanding and engagement in climate and environmental issues. We know that unity makes us strong, and collectively we can protect the environment on which all living things, including each of us, depend -- now and in the future.

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  • E2SP at the the National Science Teachers Association Conference

    Created: 6/5/2017      Updated: 6/5/2017

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    In March, two teachers from St. Malachy School got to represent our E2SP program at the National Science Teachers Association Conference. The following blog is a guest post written by them as they reflect on the experience. Want to learn more about our education programs for students and teachers? Click here.

    We are Science Teacher Leaders at St. Malachy School and part of the Early Elementary Science Partnership (E2SP) initiative sponsored by The Peggy Notebaert Nature Museum, The Field Museum, Northwestern, and Big Shoulders. We were thrilled to be invited to present with the E2SP team at the National Science Teachers Association (NSTA) conference in Los Angeles at the end of March. 

    Our first day of the conference, we attended the Elementary Extravaganza. The event is held in a large hall and there are teachers from all over the country and world showcasing science activities.  There were so many exciting things to see: for our personal use and to share with the other teachers in the building. Then we went to the vendor hall where we saw even more great ideas and items to enhance our science program. The workshops we attended further energized us for future plans for our school.

    Our presentation was on using protocols to enhance science professional learning communities (aka-making science meetings helpful). We have had great success getting teachers to participate in our monthly meetings due to our use of the protocols we have learned from E2SP. After a brief introduction to the program and our school, we actually led a protocol with workshop attendees. The feedback from the participants was so positive. We left with almost as many ideas from the lively discussions.

    We are so grateful to Big Shoulders for sponsoring our travel and E2SP for including us in the presentation. We came back with so many great ideas for our school. Patti was so excited, she wrote a proposal to do her own presentation next year in Atlanta: who wants to join her?

    Patti Taylor and Kaylyn Wardrip
    St. Malachy School

    You can learn more about our education programs by clicking here.

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  • How Many Legs Does a Caterpillar Have?

    Created: 5/17/2017      Updated: 5/18/2017

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    Looking at this picture, you might conclude that caterpillars have 8 pairs of legs- three pairs in the front, four in the middle and one at the back (if you're a bit confused, the head of the caterpillar is on the left in this photo). But wait, aren't caterpillars insects? Don't insects have 6 legs, not 16?

    Like all insects, this caterpillar has only 6 legs. Note the different shape of the three pairs of legs near the caterpillar's head. They're the true legs. The remaining structures are not legs at all. They're protrusions from the caterpillar's abdomen called prolegs. Much like true legs, they help the caterpillar grip onto surfaces like twigs, and aid in locomotion.

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  • Why do Birds Fly in Formation?

    Created: 5/16/2017      Updated: 5/17/2017

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    In this series, we'll be addressing some common questions from visitors and readers. Do you have a science question that has you stumped? Ask our museum scientists via our form here and we'll answer it on our blog!

    Today's Question:

    Why do birds fly in formation?

    If you've spent a year in the United States, then you've heard the honks and seen the distinctive v-shaped flying pattern of Canada geese. But geese aren't the only birds to fly in an orderly pattern: pelicans and ibises adopt the same v-shape when flying in flocks.[1] What do these birds have in common, and what benefit do they gain from flying in a "v" shape?

    Geese, pelicans, and ibises are examples of birds that migrate. Migration is the seasonal movement of animals in search of food sources or breeding grounds: geese fly south during the winter to find food and water; sea turtles travel between nesting sites on land and their feeding grounds on the coast; and college students return to their parents' homes in May when the cafeteria closes.

    Those aren't geese: these Eurasian Cranes also adopt a v-formation when migrating.[2]

    Migration over long distances requires a lot of energy, so when migrating it is a great advantage for animals to save energy however possible. Animals will need less food, and the migration will take less time. That's where the v-formation comes in handy: scientific studies have shown that geese flying in formation may spend only half as much energy than if they flew alone or in some other shape.[3] This is also why a squadron of jets will adopt the same v-shape: it takes less fuel for the aircraft to fly. Birds and jets are both able to gain extra lift by flying in the updraft that is created by the flyer in front of it.[1]

    Not all migrating birds fly in a v-shape: varieties of hummingbirds, finches, and sparrows all migrate,[4] but these birds are too small to gain an energy-saving benefit from flying in formation. Not all migrating birds even fly, for that matter: the flightless emu from Australia migrates too, but does so on foot. And no, migrating emus do not run in formation.[5]

    But wait, there's more: There are other flying formations that the classic “v”! When birds flock in large groups in the air, this is also a deliberate formation. It's a defense mechanism that protects against predators: every bird is safer when they're in the flock. It's difficult for a predator to single out an individual from the flock, and a bird that leaves the flock is more likely to be eaten by a predator.[6] The whole flock moves as one in order to protect every member. Starlings are well-known for their flocking behavior, and there is even a specific term -- a murmuration -- to describe a flock of starlings. It is absolutely worth watching this two-minute video from National Geographic to see a murmuration in action: 

    Kyle Schiber
    Nature Museum Volunteer

    [1] Yong, Ed. “Not Exactly Rocket Science, A Blog by Ed Yong”. Birds that Fly in a V Formation Use An Amazing Trick. Retrieved May 5, 2017, from


    By Hamid Hajihusseini ( [CC BY 3.0 (], via Wikimedia Commons

    [3] Cuttis, C.J. and Speakman, J.R. Energy Savings in Formation Flight of Pink-Footed Geese. Retrieved May 7, 2017 from

    [4] The Nature Conservancy. “Managing Habitats for Migrating Land Birds in the Western Lake Erie Basin” (2008)

    [5] The Animal Corner (2017). Retrieved May 14, 2017 from

    [6] Flight Plan. “How a Flock of Birds Can Fly and Move Together” (April, 2009)

    Do you have a science question that has you stumped? Ask our museum scientists via our form here and we'll answer it on our blog!

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