The True History of the World: Chapter 2 DINOSAURS!
Wait. I thought this post was going to be about aliens!
I know, I know… I promised you aliens, but, eh… I lied. Whatcha gonna do? Since you’re here, though, how ‘bout we take a look at some of the more prevalent misconceptions concerning dinosaurs. In a way, the world of the dinosaurs is about as alien to us as it gets, so let’s yabba-dabba-do this!
Dinosaurs were the biggest creatures that ever existed on earth.
No, they weren’t.
Firstly, not all dinosaurs were large; some of them were actually quite small. The sheer diversity of dinosaurs' sizes is impressive in and of itself, but the thing to remember here is that dinosaurs existed over a span of millions and millions of years, so they came in an enormous variety of shapes and sizes. It’s true that some dinosaurs were monstrously huge; however, there were many others that were dog-sized, some even as small as a chicken. We’ll discuss the velociraptor in particular in a moment, but to more specifically address the misconception that dinosaurs were the biggest creatures ever, let’s take a look at what was possibly the largest dinosaur of all: Maraapunisaurus.
Maraapunisaurus was a land-dwelling herbivorous sauropod that lived in what is now western North America during the late Jurassic period (145-165 million years ago). Although no complete examples exist, and the partial specimens we do have are few and far between and in poor condition, several analyses corroborate an upper estimate of up to 200 feet in length (nose to tail) and about 120 metric tons in weight (≈265,000 lbs). I will concede that Maraapunisaurus is probably the largest animal to ever walk on land, BUT…
Enter the blue whale.
Do not enter the whale, Jonah. I just mean… never mind. Today, anywhere from five- to fifteen-thousand blue whales can be found swimming in almost every part of every ocean everywhere, and while they only reach about half the length of Maraapunisaurus, blue whales can tip the scales at close to 200 metric tons (441,000 lbs), making them, without question, the most massive creature to ever exist on this planet.
Jurassic Park was basically a documentary, right?
Earlier, I hinted at a misconception regarding the velociraptor, made famous by the 1993 film Jurassic Park, which was itself an adaptation of Michael Crichton’s novel of the same name. Let me begin by stating, for the record, that I like Jurassic Park. Thirty years on, it still holds up, BUT… that movie has done more to spread misinformation about dinosaurs than any other work EVER.
So… the velociraptor. Where do I start?
To begin with, the velociraptors would’ve more rightly belonged in a Cretaceous Park, not Jurassic, but… eh. Whatever.
The size of the velociraptors in Jurassic Park were partly a production necessity, as many of the creatures were actually performed by actors in creature suits. This not only made them much larger than real velociraptors, but altered their body shape some, as well. Stan Winston, JP’s creature creator said in interviews that the film’s stars were actually more loosely based on a different dino, called deinonychus (also a type of raptor), than on the v. mongoliensis.
Even the deinonychus in the film, though, had been doubled in size compared to reality. Real raptors were evolutionarily much closer to modern birds than big, scary lizard monsters: they were covered in feathers (as is evidenced by quill nubs on their skeletons), and were warm-blooded animals measuring about two to three feet in height, and weighing in at around 20 kg (44 lbs). There is also no scientific reason to think that velociraptors could run very fast, hunted in flocks (they’ve never been found in groups), or possessed any kind of highly-developed intelligence. All this is nothing more than creative license.
Unlike many of the animals featured in the film, dilophosaurus at least actually did live during the Jurassic period. Despite its colourful interpretation, though, this dino's portrayal was almost entirely artistic liberty.
Right off the bat, it is very unlikely that dilophosaurus spat venom at its prey. In most living venomous animals, there are distinct pits in the jaw bone indicative of a toxin delivery system. Dr. Susie Maidment of the Natural History Museum, London, says, “We don't have any evidence that dilophosaurus, or in fact any dinosaurs, were able to produce venom. It also had this frill in the film, and we don't have any evidence for that either.”
The film's version of dilophosaurus was also undersized, which is, again, a matter of production necessity. Despite the movie’s typical approach of making its creatures bigger for dramatic effect, the real-life dilophosaurus (about 6 m or 20 ft in length) was scaled down to make it appear less threatening, and able to fit inside Nedry’s jeep.
Oh, the mighty T. rex was also a resident of the Cretaceous period, not the Jurassic.
“In the first Jurassic Park a Tyrannosaurus chases down an accelerating jeep. People have looked at running speeds of dinosaurs, and the most recent research suggests that T. rex could barely run faster than a human,” according to Dr. Maidment.
Even the film’s consulting paleontologists did not approve of the Tyrannosaurus’ speed in the film, but animator Steve Williams (no relation) decided to “throw physics out the window and create a T. rex that moved at sixty miles per hour even though its hollow bones would have busted if it ran that fast”.
In reality, T. rex probably had a top speed of only around 16 kph (10 mph), but the dinosaurs it preyed on wouldn't have been moving much faster than that either, and don’t think that standing still would fool one. The motion-based sight capabilities seen in JP are just another creative liberty. Tyrannosaurus was likely a fairly proficient hunter, albeit a slow one. Long-term studies have shown that T. rex had binocular vision like a bird of prey, and that their angle of vision was even greater than that of modern hawks! According to Kent Stevens of the University of Oregon, the Tyrannosaur’s vision was about 13 times clearer than ours, and they could see objects at a distance of up to 6 km as clearly as we see them 1.6 km away.
Ok, so a real-life Jurassic Park might look a little different, but it’d still be cool.Michael Crichton came up with a very compelling and plausible-sounding theory that you could extract dino-DNA from the blood inside preserved mosquitoes, but, as far as cloning goes, and the possibility of a real-life Jurassic Park ever coming to fruition, there are two seemingly irresolvable hurdles that would need to be addressed.
According to a study featured in the May 2003 issue of Science, due to chemical instability and environmental contamination, DNA has a life expectancy, and it is way less than what would be needed to clone a dinosaur. Evolutionary geneticist Eske Willerslev and geogeneticist Anders J. Hansen posited in Current Biology that “even under the best preservation conditions, there is an upper boundary of 0.4–1.5 million years for a sample to contain sufficient DNA for contemporary sequencing technologies”. [Full disclosure: Anders Hansen and I have a great-great-grandfather in common.]
On top of that, even if it were somehow someday possible to extract clean, useable DNA from a 65+ million-year-old dinosaur, and you were able to successfully clone it, I have one word for you:
There just isn’t enough oxygen in today’s atmosphere to support dinosaurs, who evolved specifically to thrive in an environment that was closer to 30% oxygen. If you suddenly introduced one of those animals into our 21% oxygen air, it would suffocate, and that would make for a very short and sad movie.
Fine! Jurassic Park got everything wrong. Let’s just focus on REAL dinosaurs then.
Ok… which ones?
What about the flying ones?
A lot of people think the pterosaurs, like the iconic pteranodon, were flying dinosaurs, and given their webbed forelimb shape, that makes sense, but the reality is that all dinosaurs were actually terrestrial creatures, with thousands of species living out their lives for millions and millions of years on land. Their bones were too heavy, they didn’t have enough upper body musculature, and, although they did have surprisingly fast metabolisms, they couldn’t metabolise fast enough to overcome the energy requirements of getting airborne.
Really? But weren’t they the precursors of modern birds?
Most scientists today accept that modern birds are, in fact, a specialised subgroup of the theropods (like T. rex), and while the previously clear distinction between non-birds and birds has become rather blurry, we do know that none of the “dinosaur era” animals were capable of ground-to-air flight, though it’s possible some (like Archaeopteryx) could glide from heights.
Modern birds have evolved with lightweight skeletons, two large pectoralis muscles (accounting for 15% of their total mass), the supracoracoideus, as well as elongated forelimbs that serve as aerofoils (aka “wings”).
How are there still birds, though, if the meteor killed all the dinosaurs?
Here’s the thing to remember, there were dinosaurs on the earth for about 180 million years, but they didn’t all just appear overnight, nor did they disappear as quickly.
Popular images abound of this six-mile wide meteor crashing into the earth, throwing up clouds of dirt and debris, blocking out the sun, and ultimately killing off the dinosaurs in the persistent winter that followed.
The evidence for a major meteor impact at the end of the Cretaceous period is well documented and overwhelmingly accepted. This includes a large (partially submerged) crater over 100km wide in Mexico’s Yucatan peninsula, as well as a worldwide spike in iridium, an element that is extremely rare on earth, but abundant in meteorites.
There is, however, growing evidence that the meteor impact wasn’t the only factor in the disappearance of the dinosaurs. Remember that these were likely warm-blooded creatures, and this was far from being the only meteor impact of the era.
It seems that the Chicxulub impact event was merely the straw that broke the Dromaeosaurus’ back, so to speak.
A devastating series of conditions across the globe did in 70% of all species living then. Massive volcanic eruptions during the Late Cretaceous period transformed the Indian subcontinent into a hellish landscape of lava-gushing fissures, lava lakes hundreds of kilometres across, and lava flows hundreds of kilometres long. That’s a lotta lava! These eruptions were accompanied by outgassing of substantial quantities of carbon dioxide and sulfur dioxide, altering the composition of the atmosphere and the oceans, and putting entire ecosystems at risk… ecosystems that not only included the larger dinos, but that fed them as well.
There was definitely a mass extinction event 65.5 million years ago, and it did spell the end for a lot of dinosaur species, but not all of them. 30% of Cretaceous species survived the event. Many mammals, birds, reptiles, fish, plant life, amphibians, marine invertebrates, and insects survived by having omnivorous, insectivorous, and carrion-based diets, or being able to feed from detritus. In fact, some fossil finds seem to indicate that at least a few of the larger non-avian dinosaur species (including hadrosaurs) may have survived for several hundred thousand years after the Chicxulub event.
Ok, let me if I’ve got this straight: so, it went dinosaurs, birds, mammals, then people. Right?
Like I mentioned in the introduction to this series, despite often being characterized as battling each other, the gentle stegosaurus lived only a short time during the late Jurassic period, and had been extinct about 82 million years by the time the first T. rex roamed the earth. Conversely, the tyrannosaurus died out about 65.5 million years ago, meaning that it lived closer to the present day than to its fictitious rival. Likewise, while many people believe that mammals never co-existed with dinosaurs, and evolved after the non-avian dinosaurs went extinct 65.5 million years ago, that’s just not the case. In fact, mammals predate dinosaurs by about 15 million years!
Mammals evolved from a reptile called the cynodont, which looked like a scaly rat and lived more than 260 million years ago. Mammals had already diversified into marsupial and placental lines by about 165 million years ago, during the Jurassic period when dinosaurs were having their heyday. “There was never a mammal (that we know of) larger than a badger that lived with the dinosaurs,” says paleontologist Steve Brusatte at the University of Edinburgh, “but almost as soon as the non-bird dinosaurs went extinct, mammals started to diversify and spread around the world and grow to much bigger sizes.”
The first dinosaurs were probably small, bipedal predators that appeared around the Anisian epoch of the Triassic, 245 million years ago, as evidenced by remains of the genus Nyasasaurus from that period. So, during the Mesozoic Era, while dinosaurs were the rulers of the earth, many species of small, rodent-like mammals had already established their own ecological niche, and were gathering acorns for the coming Ice Age.
You know who else predates dinosaurs? Sharks.
Just an interesting fact I felt like throwing in, but sharks have been swimming around the world’s oceans for about 400 million years… even before there were trees!
What about the brontosaurus? Remember how Fred Flintstone used to drive a brontosaurus to work every day? There must’ve been lots brontosauruses living during the age of dinosaurs, right?
Are we seriously going there? Okay…
One, the brontosaurus never actually existed, and was in fact an incorrectly identified dinosaur created by putting the body of an apatosaurus together with the head of a camarasaurus.
Two, the next installment is definitely going to be on cavemen.
Jeff Williams is a professional historical consultant, a published author and copywriter, an award-winning photographer, a certified genealogist, creative designer, prop master, project manager, linguist, and adventure traveler. He has done work for Disney, Universal, Hasbro, Warner Bros., National Geographic, the Port Authority of Jamaica, and the Central Intelligence Agency.
All rights reserved. The content of this blogpost may be copied online, but may not be reproduced in print or any other media without written permission from the author.