Hey there! Did you know that Walt Disney made a creative choice in the movie Fantasia by giving the Tyrannosaurus Rex an extra finger on each hand? He thought it made the dinosaur look scarier, even though it wasn’t accurate. That’s just one of many cool facts about dinosaurs we’re going to explore today!
Dinosaurs first appeared around 230 million years ago during the Mesozoic era and lived for about 165 million years before going extinct 65 million years ago. To give you an idea of how long that is, modern humans have only been around for about 200,000 years! Scientists aren’t exactly sure why dinosaurs went extinct, but they think it was a slow process that sped up when an asteroid hit Earth.
Interestingly, a study found that 41% of adults in the U.S. believe humans and dinosaurs lived at the same time. While we do live with birds, which are technically dinosaurs, humans never coexisted with non-avian dinosaurs. The first dinosaur bones were discovered in the 1820s, and since then, we’ve identified over 700 different species!
If you’ve seen Jurassic Park, you might think you know a lot about dinosaurs, but the movie got some things wrong. For example, velociraptors were much smaller than shown in the films, standing only about 20 inches tall. Also, the Dilophosaurus didn’t spit venom as depicted in the movie. And while the film shows a Brachiosaurus standing on its hind legs, experts believe it probably didn’t do this often.
Dinosaurs are classified as either bird-hipped or lizard-hipped based on the orientation of their pubis bone. Interestingly, birds descended from lizard-hipped dinosaurs, so they don’t actually have bird hips! Some dinosaurs, like the Allosaurus, took decades to grow to full size, but many could reproduce by the age of eight.
We’re not sure if the T. rex was a top predator or if it scavenged for food. It wasn’t as big as the Dreadnoughtus, which weighed around 30 to 40 tons, compared to the T. rex’s 7 to 9 tons.
There’s a Kronosaurus skeleton at the Harvard Museum of Natural History that might be incorrect. Some think it has too many vertebrae, making it larger than a real Kronosaurus. Also, the Kronosaurus wasn’t actually a dinosaur; it was a marine reptile called a plesiosaur.
It’s often said that the Stegosaurus had a brain the size of a walnut. This idea became so popular that a paleontologist jokingly suggested using “walnut” as a unit of measurement for dinosaur brains. The name Stegosaurus means “roofed lizard” because its back plates were once thought to be flat like roofs, but we now know they stood upright.
In the Hell Creek Formation in the northern U.S., 50 Triceratops skulls have been found! Sauropod dinosaurs might have swallowed small rocks to help digest their food, a behavior seen in some animals today, like crocodiles and birds.
Dinosaurs had feathers before they were used for flying. Experts think feathers evolved for display purposes. Most dinosaur eggs were white, but some fossilized eggshells show they were blue-green.
In the 1990s, a fossilized baby dinosaur was found with its guts and windpipe well preserved. It was a new species called Cionyx samne dicus, which lived 113 million years ago. The only dinosaur fossil found in Arkansas was named the Arkansas Rex.
The Ankylosaurus had a massive club tail, possibly used for attracting mates or fighting. In 2014, a fossil was found with many baby dinosaurs and one older one, possibly a babysitter, similar to how some birds use other birds as babysitters.
Google has a T. rex replica named Stan at its headquarters. Meanwhile, Ray Stanford in Maryland has discovered 300 dinosaur tracks, which have been published in scientific journals.
Paleontologist Jack Horner believes we could create modern dinosaurs using chicken DNA, as chickens are descendants of dinosaurs. He calls this potential creature a “chickenosaurus.”
Finally, did you know that seven U.S. states have an official state dinosaur, and four more have state fossils that are dinosaurs?
Thanks for joining me on this dinosaur adventure! What’s your favorite dinosaur? Mine is the Triceratops!
Research the Mesozoic era and create a timeline that highlights the major periods when dinosaurs lived. Include key events such as the appearance of the first dinosaurs, the extinction event, and the discovery of the first dinosaur bones. Use drawings or digital tools to make your timeline visually engaging.
Use your imagination to design a new dinosaur species. Think about its habitat, diet, and unique features. Draw your dinosaur and write a short description explaining its characteristics and how it might have lived. Consider what kind of hips it would have and how it might have used feathers.
Watch a dinosaur-themed movie or a clip from one, like Jurassic Park. Identify at least three inaccuracies about dinosaurs depicted in the film. Research the real facts and present your findings in a creative way, such as a poster or a short video presentation.
Participate in a classroom debate about whether the T. rex was a top predator or a scavenger. Research evidence supporting both sides and prepare arguments. Work in teams to present your case and listen to the opposing side’s arguments. Conclude with a class discussion on what you learned.
Engage in a simulated fossil dig activity. Use tools to carefully excavate “fossils” from a sandbox or a similar setup. Once you’ve uncovered the fossils, try to identify them and piece them together like a paleontologist would. Discuss what these fossils can tell us about the dinosaurs they belonged to.
Here’s a sanitized version of the YouTube transcript:
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Hey there, I’m Mike! Welcome to the Mental Floss video. Did you know that Walt Disney insisted on an anatomically incorrect Tyrannosaurus Rex in the film *Fantasia*? He knew that the dinosaur only had two fingers on each hand but added an extra finger per hand because he thought it looked better and scarier. I think he was right! That’s just the first of many facts about non-avian dinosaurs that I’m going to share with you today.
Let’s start with some dinosaur basics. Dinosaurs probably emerged around 230 million years ago during the Mesozoic era and then died out 65 million years ago, meaning they were around for about 165 million years total. To put that in perspective, modern humans have only existed for about 200,000 years. So, 165 million years is enough time for a ton of different dinosaur species! We don’t know exactly why they went extinct, but it was probably a long process. Experts believe that dinosaurs were already declining when an asteroid hit the Earth, which accelerated their extinction.
According to one study, 41 percent of adults in the U.S. think that humans and dinosaurs coexisted. While we do live alongside birds, which are technically dinosaurs, we never lived alongside non-avian dinosaurs. Humans first discovered dinosaur bones in the 1820s, and now we know of over 700 different species of dinosaurs thanks to many discoveries since then.
If you think you know all there is to know about dinosaurs because you’ve seen *Jurassic Park*, think again! The movie actually got some dinosaur facts wrong. For example, velociraptors were definitely not as large as they appear in the films; in reality, they were probably about 20 inches tall. In both the film and the book, a Dilophosaurus shoots venom causing blindness and paralysis, but this was completely made up for dramatic effect. Experts don’t believe that the Dilophosaurus was venomous at all. The film also shows a Brachiosaurus standing on its hind legs, but according to expert Dr. Heinrich Malleson, the animal was probably unlikely to use a bipedal posture regularly or for an extended period of time.
Dinosaurs are classified as either bird-hipped or lizard-hipped, which has to do with the orientation of the pubis bone. Interestingly, birds descended from lizard-hipped dinosaurs, so technically, birds don’t have bird hips. It took some dinosaurs decades to grow to full size; for instance, an Allosaurus may have taken 30 years to mature. However, many dinosaurs were able to reproduce by the age of eight.
We still don’t know if the T. rex was a major predator. Some scientists believe they were scavengers or at least scavenged in addition to hunting. Don’t be too disappointed; the T. rex wasn’t that big compared to the Dreadnoughtus, which was probably around 30 to 40 tons, while a T. rex was more like 7 to 9 tons.
There’s a Kronosaurus on display at the Harvard Museum of Natural History that might contain an error. Some believe that the people who assembled it added too many vertebrae, making it larger than a real Kronosaurus would be. Also, the Kronosaurus wasn’t technically a dinosaur; it was a plesiosaur, which were marine reptiles that lived during the Jurassic and Cretaceous periods.
It’s often repeated that Stegosaurus had brains the size of walnuts. This notion became so popular that in 2013, paleontologist Lawrence Whitmer jokingly proposed that “walnut” become the standard unit of measurement for dinosaur brain size. Speaking of Stegosaurus, their name means “roofed lizard” because when they were first discovered, paleontologists believed that the plates on their backs were flat, making them look like they had roofs. We now believe that the plates stood upright.
Moving on to another famous dinosaur, the Triceratops: there’s a region in the northern U.S. known as the Hell Creek Formation, where a whopping 50 Triceratops skulls have been found so far. It’s believed that sauropod dinosaurs used to swallow small rocks to help with digestion, a behavior still seen in some animals today, including crocodiles and birds.
Thanks to dinosaurs, there were feathers before they were used for flight. Experts think that feathers evolved on dinosaurs for display purposes. The majority of dinosaur eggs were white, but scientists have found pigments in some fossilized eggshells revealing that they were a blue-green color.
In the 1990s, a fossilized baby dinosaur was found with its guts and windpipe fairly well preserved. It was also the discovery of a new species, *Cionyx samne dicus*, which was 113 million years old. The fossil of only one dinosaur has ever been found in the state of Arkansas, and it was named the Arkansas Rex.
Another dinosaur starting with the letter A, the Ankylosaurus, had a huge club tail that may have been used to attract mates or possibly fight—or why not both? In 2014, a 120-million-year-old fossil was found that contained many baby dinosaurs in addition to one older one. Experts think that the older dinosaur was too young to be the parent of the babies, so it could have been a babysitting dinosaur, which wouldn’t be too outlandish since some birds use other birds as babysitters.
Google has its own dinosaur, of course—a huge T. rex replica named Stan that sits outside of the company’s headquarters. Well, guess what, Google? We have our own T. rex! There’s a man named Ray Stanford who has an amazing ability to sense dinosaur tracks. He lives in Maryland and has found 300 tracks that have been published in scientific journals. Stanford also has 3 tons of rocks containing dinosaur tracks.
Speaking of dinosaur experts, paleontologist Jack Horner has claimed that modern dinosaurs could be made if we get the right DNA from chickens, which are said to be descendants of dinosaurs. He calls his proposed end result the “chickenosaurus.”
Finally, I returned to the salon, but did I ever really leave? To tell you that there are seven states in the U.S. with an official state dinosaur, and four additional states have official state fossils that happen to be dinosaurs.
Thanks for watching Mental Floss video, which is made with the help of all these very nice people. Once again, my name is Mike Rugnetta. If you like my face, you can see more of it on my YouTube show, Idea Channel, and if you like my voice, you can hear more of it on my podcast, Reasonably Sound. Let me know your favorite dinosaur in the comments—I think mine is Triceratops!
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This version removes informal language and maintains a more polished tone while preserving the original information.
Dinosaurs – Large reptiles that lived millions of years ago during the Mesozoic Era. – Scientists study dinosaur bones to learn more about how these ancient creatures lived.
Extinction – The permanent disappearance of a species from Earth. – The extinction of the dinosaurs is believed to have been caused by a massive asteroid impact.
Feathers – Structures made of keratin that cover the bodies of birds and some dinosaurs, used for flight and insulation. – Fossils have shown that some dinosaurs had feathers, suggesting they might be ancestors of modern birds.
Species – A group of organisms that can interbreed and produce fertile offspring. – The giant panda is a species that is currently endangered due to habitat loss.
Predators – Animals that hunt and eat other animals for food. – In the prehistoric world, the Tyrannosaurus rex was one of the most feared predators.
Fossils – Preserved remains or traces of ancient organisms found in rocks. – Fossils provide important evidence about the history of life on Earth.
Eggs – Reproductive structures laid by female animals, containing embryos that develop into new individuals. – Dinosaur eggs have been discovered in various parts of the world, giving insight into their reproductive habits.
Growth – The process by which organisms increase in size and develop over time. – The growth of a plant can be affected by factors such as sunlight and water availability.
Classification – The process of organizing living things into groups based on their similarities. – Scientists use classification to better understand the relationships between different species.
Evolution – The process by which species change over time through natural selection and genetic variation. – The theory of evolution explains how modern animals have descended from ancient ancestors.
