How did pterosaurs fly?

At the Science Mill, we love dinosaurs—we’re guessing you do, too! But in this blog, we want to show some love to pterosaurs: prehistoric flying reptiles that lived among dinosaurs, but were NOT dinosaurs. 

In case you missed Part 1, pterosaurs ranged in size from sparrows to Cessna airplanes and had wild adaptations, including big heads, crazy crests and special membrane wings supported by super-long 4th fingers. What’s not to love?!

If dinosaurs ruled the Earth, pterosaurs definitely ruled the skies. But how they flew is a mystery paleontologists are still piecing together. You can try flying as a pterosaur in Jurassic Flight 4D, the Science Mill’s new 4D virtual reality experience! To celebrate its opening, join us Saturday, May 29 for Jurassic Experience, a day of dino-themed activities and special screenings of Flying Monsters, which features some of the paleontologists in this blog.

(artist: Chase Stone)

How did pterosaurs fly?

This is one of the big debates about pterosaurs: were all of them really able to fly—even the giraffe-sized species? This is where mathematics and computer models come in.

One computer simulation, developed by paleontologist Sankar Chatterjee and his team at Texas Tech University, suggests that an animal the size of a fighter jet would need a runway. “It probably had to find a sloping area like a riverbank,” explains Dr. Chatterjee, “then run quickly on four feet, then two, to pick up enough power to get into the air.” Once in the air, it was a graceful if frightening sight. “This animal probably flew like an albatross or a frigate bird in that it could soar and glide very well.”

Paleontologist Michael B. Habib and others have a different theory, based on computer simulations of pterosaurs’ launch power—no runway needed. “Flying animals do not flap their way into the air,” notes Dr. Habib. Instead, takeoff starts with a powerful jump, and four-limbed pterosaurs had double the power. “The legs would have pushed first, followed by the arms, for a perfect one-two push-off.” Some have compared the move to pole-vaulting. 

(credit: Julia Molnar, via Scientific American)

But what about those enormous heads? If pterosaurs flew with their wings angled forward, as calculations by Dr. Colin Palmer and his team suggest, their big heads would be balanced. New fossils offer additional clues. CT scans of a pterosaur vertebrae recently revealed a strength-building secret: a “tube within a tube” structure supported by spokes, similar to a bicycle wheel. Paleontologist Cariad Williams and her team calculate that for a pterosaur with a 4-foot neck, adding just 50 spokes to its vertebrae would allow it to lift 90% more weight—roughly equal to picking up prey that weighed 24 pounds. 

Are there pterosaurs living today?

No—pterosaurs went extinct at the end of the Cretaceous period. While birds evolved from dinosaurs, pterosaurs have no living descendants. They do, however, have mechanical relatives! 

Experimental designs for Pterodrone (images: Brian Roberts)

Dr. Chatterjee and Rick Lind, an aeronautical engineer, teamed up to create a drone inspired by pterosaurs’ unique flying adaptations. Named “Pterodrone,” the drone’s design includes membrane-inspired morphing wings and an adjustable crest in the front. The features make the drone a more versatile flier in tight spaces. In the future, they hope to add the pterosaurs’ ability to walk and possibly sail.

TRY IT AT HOME OR SCHOOL

Animal Design Challenge

Research on pterosaurs helped Dr. Chatterjee and Dr. Lind design a new drone. Their work used biomimicry: an approach to technological innovation that draws ideas from nature. To experiment with biomimicry, try this Animal Design Challenge alone, with a partner or with a group!

 Supplies

• Slips of paper, index cards or Post-its (enough for each participant to get two)

• Pencils or pens for writing

• Colored pencils, crayons or markers for drawing

Dr. Chatterjee with a skeleton reconstruction of the pterosaur that inspired the Pterodrone’s design. (credit: AP Photo/Artie Ummer)

1. On half the cards, write an animal—one per card. (Prehistoric animals are fair game!)

2. On the other half of the cards, write a short everyday problem—one per card. (EX: Keep construction workers safe; chop up vegetables; carry a heavy bag)

3. Mix up the animal cards and have each person take one; mix up the problem cards and have each person take one of those, too.

4. Brainstorm! How could your animal inspire a solution to your problem? Maybe something about their body? How they move, or where they live? Jot down your ideas.

5. Design! Pick one of your ideas and sketch out a prototype for a new product or system. Try to show how it would work.

6. If you’re working solo, pick another animal card and see if you can add on to your prototype; or pick another problem card, too, and start again!

7. If you’re working with a partner or group, share your ideas. After seeing everyone’s animals, problems and prototypes, what new combinations do you see for biomimicry inspiration?

8. Keep observing and brainstorming! Study plants and animals outside, a pet at home—who knows where your next big idea might come from?

CAREER CONNECTION
“An aircraft based on pterosaur concepts may be able to fly to a rooftop then walk under an overhang to mount a sensor in a dark corner.” — paleontologist Sankar Chatterjee and aeronautical engineers Rick Lind and Brian Roberts, on their inspiration for Pterdrone

MORE TO EXPLORE
Explorer Zone Episode 4: Masters of Disguise

Labs on the Go: Bug Inspired Biomimicry (Grades 6-8)
Check out our new Labs on the Go series for Grades K-8: Each Lab combines hands-on STEM activities with video “field trips” that show science in action. Everything you need ships directly to your classroom and is supported through an easy-to-navigate online learning system!

Is a pterosaur a dinosaur?

Do you have a favorite dinosaur? Celebrate it on May 18—International Dinosaur Day! (In fact, dinos are so big, they get two holidays: June 1 is International Dinosaur Day, too.)

Do you also have a favorite pterosaur? If you’re thinking, “What’s a pterosaur?” or “Isn’t that a dinosaur?”, read on! This is Part 1 of a two-part feature on pterosaurs, some of the weirdest, coolest creatures to ever fly. At the end of this post, you’ll find a DIY activity to make your own pterosaur!

Flocks of pterosaurs will (virtually) take to the sky this summer in Jurassic Flight 4D, the Science Mill’s new 4D virtual reality experience that lets you fly as a pterosaur through a world of dinosaurs. Join us Saturday, May 29 for Jurassic Experience, a day of dino-themed activities and the exhibit’s grand opening.

(artists: Julius Csotonyi and Alexandra Lefort, via National Park Service/ Big Bend National Park)

What’s a pterosaur?

Pterosaurs (the “p” is silent) were flying reptiles that lived 228 to 65 million years ago. They were the world’s first flying vertebrates, reaching new heights millions of years before modern birds and bats. Pterosaurs didn’t just leap or glide between heights, the way some reptiles do today. They were true fliers who could create lift by flapping their wings—what scientists call “powered flight.” (But there’s debate about how they flew; more on that in Part 2!)

“Pterosaur” isn’t one kind of animal: it’s actually a whole bunch of related species. The general name we use comes from Pterosauria, the scientific order that groups together these flying reptiles. For comparison, another order is Primates, which groups together apes, lemurs, lorises, tarsiers, monkeys and humans. 

Are pterosaurs a kind of dinosaur?

Nope, pterosaurs are NOT dinosaurs. They are cousins, who share a common ancestor but evolved into distinct groups. That might seem confusing: pterosaurs lived at the same time as dinosaurs and, well, don’t they look like dinosaurs?!

Scientific classifications go more than skin deep; they’re based in a careful study of anatomy that helps scientists better understand and organize both living and extinct creatures. Part of what separates dinosaurs from pterosaurs are their hip and arm bones. All dinosaurs have a hole in their hip socket and a crest on their upper arm bone; all pterosaurs do not. This video with paleontologist Danny Barta helps explain.

What did pterosaurs look like?

Pterosaur species came in every size, “from that of a sparrow to a Cessna plane with a wingspan of 35 feet,” describes Sankar Chatterjee, a paleontologist at Texas Tech University. Kepodactylus, the pterosaur you’ll fly as in Jurassic Flight 4D, had a wingspan around 8 feet.

How Kepodactylus may have looked in life. (artist: Franz Anthony, via Pteros)

Small, big-eyed Anurognathus may have chased down insects at dusk. (artist: Laurence Viollet)

Pterodaustro could have used its curved jaws, filled with hundreds of needle-like teeth, to strain tiny critters from the water—like modern-day flamingos. (artist: N. Tamura)

Toothless Pteranodon likely soared over the prehistoric seas, gulping down fish like a pelican. (artist: James Gurney)

Some sharp-toothed pterosaurs may have snapped up baby dinos. (artist: Mark Witton)

Pterosaurs share some very strange anatomical features. “They evolved some of the most extreme adaptations of any animal,” says paleontologist Michael B. Habib.

(source: MacMillan Learning)

• Looooong “wing fingers”: Unlike birds or bats, pterosaur wings ran along the sides of their bodies and were held up by a super-long fourth digit—the equivalent of our ring fingers. (Pterodactylus, one of the most famous pterosaurs, is actually named for this feature: ptero = wing and dactyl = finger.)

• Shape-shifting wings: Sandwiched inside their wing membranes were layers of blood vessels, muscles and actinofibrils—chord-like fibers that made the membrane rigid yet flexible. One theory is that the muscles and fibers may have allowed pterosaurs to change the shape of their wings in flight.

• Feathery fur?: Pterosaurs’ bodies were covered in pycnofibers—scientists aren’t sure if this fuzz was more like fur, feathers (think: baby chick) or hair. The covering probably helped pterosaurs control their body temperature.

How would you measure up against Quetzalcoatlus? (artist: Mark Whitton)

• Crazy crests: Many pterosaur species had crests on their heads. Some crests were fleshy, some bony and others had a membrane “sail.” Crests might have helped regulate heat or balanced out long jaws. Most likely, they served to attract a mate. Scientists think some crests were brightly colored for extra flair!

• Long necks + BIG heads: Pterosaurs had oddly proportioned bodies with big heads. Some species’ skulls and necks were well over half their body length. Mega-sized Quetzalcoatlus, found in Texas, had a head and neck that made up 75% of its length, with jaws twice the length of a T.rex’s!

How did an animal the size of a giraffe, with an enormous head, manage to fly? ...Or did it? Find out in Part 2!

TRY IT AT HOME OR SCHOOL

Fold an origami pterosaur
Make a paper pterosaur that shows off some of their extreme adaptations: big heads with long jaws, crests and, of course, those amazing wings. You’ll need a square piece of paper to get started. Click the links below to download instructions.

12-step pterosaur (designed by Nick Robinson)

25-step pterosaur (designed by Fernando Gilgado Gomez)

CAREER CONNECTION:
“The cool thing about origami is that it is a very mathematical art...You can do things with pure art, you can do things with pure math, but if you put them together, you get far more satisfying results than either one alone.” - Robert Lang, physicist and origami artist 

MORE TO EXPLORE
Learn how Robert Lang used artistry and computer programming to design a life-size origami Pteranodon for the Redpath Museum in Montreal!

13 ways to help butterflies and bees

April 22 is Earth Day! To celebrate our planet’s amazing pollinators, we’ve put together a list of 13 ways you can help butterflies and bees. For more ideas, visit our blog post “Make Your Yard a Pollinator Pit Stop” for beginner-friendly plant guides and citizen science projects.

Join the Science Mill’s Butterfly Bonanza (+ Bats & Bees) on Saturday, April 24 from 10am-2pm for up-close encounters with pollinators and all-ages activities.

13 ways to help butterflies and bees:

• Plant native species with a variety of shapes, colors and blooming seasons

• Add a border of native flowers around your vegetable garden

• To sync with pollinators, garden by early spring and don’t clip late blooms in the fall

• Create a butterfly feeder

• Give thirsty bees a drink (but it’s best to avoid sugar water)

• Find places in your yard to protect bare soil and brush for native bees to nest

• Build a bee condo or bee hotel for native bees

• Avoid chemicals on your yard and when you buy plants and seeds (some are pretreated)

• Support the reduced use of neonicotinoid pesticides that harm bees

• Invite natural “pest assassins” into your yard

• Rethink weeds: dandelions offer bees some of spring’s first nectar

• Rethink lawns: non-flowering grass + little plant diversity = pollinator dead zones

• Relocate beehives with professional help instead of exterminating

(Visit the Science Mill’s Butterfly Garden to see these beautiful blooms and many others!)

Make Your Yard a Pollinator Pit Stop With Butterfly- and Bee-Friendly Plants

If you’re feeling that spring itch to explore outdoors, know that you’re not alone: pollinators are all a-buzz (or a-flap?) too! You’ll spot butterflies, bees and other insects—even bats, if you’re lucky—as they visit spring blooms, spreading pollen as they go to help plants form new seeds.

April is Citizen Science Month, so let’s look at ways we can support the butterflies and bees that make our world more vibrant, diverse and delicious. We’ll be celebrating pollinators (and Earth Day) at our annual Butterfly Bonanza on April 24th! 

Help monarchs on the move

Around the time Texans store away their warm coats, monarch butterflies stir from their winter retreat in Mexico and prepare to migrate north. By early April, they’ve arrived in Texas, ready to lay their eggs. Those eggs will hatch and continue north as adults, laying their own eggs along the way in an amazing multi-generational relay race that spans from Canada to Mexico.

Tracking their journey are citizen scientists—everyday folks gathering data to support scientific research—who share their sightings, count butterflies and map the location of milkweed plants where monarchs lay their eggs. Unfortunately, this year’s reports show the current monarch population is down 26% from 2019. Climate change and loss of wild habitat are major factors.

To help monarchs and other butterflies, you can create a homegrown pit stop with butterfly-friendly plants. “Supporting butterflies requires both nectar plants and host plants,” explained Kirk Alston, a horticultural specialist at The Natural Gardener. “Begin with nectar plants, as they are colorful and easy to grow. With the host plants—where eggs hatch and caterpillars feast—plan to install more than you might think: the little angels will eat your plants to the ground! They will eventually re-grow, but it takes some time, and you’ll need plenty to support the caterpillars’ journey to their future life. Milkweed is a great host plant for monarchs and queen butterflies; Dutchman’s Pipevine is a great for pipevine swallowtails.”

The Science Mill’s butterfly garden guide shows some of the best plants for central Texas and how much light they need, so you can find what works for your yard. Ideally, Kirk notes, a garden should have blooms in each season; this supports more pollinators and adds a colorful element while other plants move through their life cycles. “I love gardens that are a mix of annuals, perennials, natives and exotics, plus flowering trees and shrubs,” said Kirk. “While our nursery specializes in plants native to Texas and we are big advocates for their use, we also rely on highly adaptive plants. For instance, Tropical Milkweed (Asclepias curassavica) is native to the Caribbean, but is our prime attractor of monarchs when laying their eggs. It grows very well in Central Texas and our garden would not be complete without it.”

Meet the native bees of Texas

In addition to being a monarch haven, Texas is home to a remarkable variety of bees: over 800 species—about one-fourth of North America’s bee diversity—have been identified here.

As pollinators, bees support an estimated one in three bites of our food. We tend to think of honey bees, brought to North America from Europe in the 1500-1600s, as the “queen bees” of pollination. But native bees (species naturally found here) can be two to three times more effective at pollinating crops, like alfalfa, tomatoes and watermelon. Some have coevolved with plants to become pollination “specialists,” such as blueberry bees, squash bees and orchard bees. Our beloved bluebonnets and other Texas wildflowers rely on them, too.

Unfortunately, declining numbers is something native bees have in common with honey bees. You may have heard about the Colony Collapse Disorder that has decimated honey bees. Threats to wild bees are more diverse, but pesticides, loss of habitat and limited diet, which lead to weakened immune systems, are a big part of the problem.

Adding bee-friendly plants to your yard is a great way to help. To get started, Kirk has suggested a mix of plants to provide bees with blooms across the seasons (see graphic). You can also create spaces for native bees to nest. Don’t worry, your yard won’t be swarmed. Unlike honey bees’ communal hives, almost all native bees are solitary: about 70% of native Texas bees nest in the ground, while others nest inside stems, wood or rocky crevices. And if a honey bee hive is too close for comfort, don’t call an exterminator: bring in a bee removal specialist to safely relocate them instead.

RESOURCE: Photo guides to help you ID native Texas pollinators

VIDEO: See a hive rescue in action (leave this to the professionals!)