Some Awesome Dinosaurs

Thursday, February 20, 2020

Quite an unfortunate situation to be in. Luckily, T-Rex lived some 66 million years before jeans ever became a thing. Image credits: Schwoaze.

So, you love dinosaurs. You’re probably familiar with the T. rexthe Triceratops, and the Stegosaurus but you want more. Well, don’t worry, cause we’ll give you more.

It would far too long to go through all the dinosaur species we know existed, so we’ll have a look at some of the most representative dinosaurs, discuss what their name means, what they looked like, and add in a little bit of trivia. But first, let’s look at how dinosaurs as a group got their name.

How dinosaurs got their name?

The term was coined in 1842 by English biologist Sir Richard Owen. The name dinosaur literally means “terrible lizards”, which we can safely say is a pretty fair description (at least in most cases). It comes from two Greek words: deinos, a name that means “terrible”, and saurus, which means lizard.

As for the individual species, they were named in different ways. Often, dinosaurs are named for a distinctive characteristic. Baryonyx means heavy claw. Corythosaurus means helmet lizard. Tyrannosaurus means tyrant lizard — you get the point. Other times, they’re named after the place where the first fossil was found, like Albertasaurus (from Alberta, Canada).

Before we start looking into individual species and their names, there are a few other Greek roots that can help you better understand dinosaur names.

  • Draco: from Rakon – means Dragon;

  • Hippos: from Hippos – means Horse;

  • Hydro: from Hydro – means Water;

  • Ortho: from Orthos – means Straight, Right, or Upright;

  • Macro: from Makros – means Large;

  • Micro: from Mikros – means Small;

  • Mega: from Megas – means Huge;

  • Morph: from Morph – means Shape;

  • Poly: from Polys – means Many.

Now that we’ve got the boring stuff out of the way, let’s finally look at some dinosaurs.

Tyrannosaurus rex

Scotty The T-Rex. By BangBooDoragon

Let’s start with the king: Tyrannosaurus rex means the “Tyrant Lizard King”, and you could hardly imagine a better name. It was named in 1905 by Henry Fairfield Osborn, who was then the president of the American Museum of Natural History.

T. rex, as it is often called, lived in the late Cretaceous, the very last period when dinosaurs ruled the Earth. Although it seems that T. rex “only” lived for 2 million years (a relatively short period, compared to other dinosaurs), it made quite an impact.

It’s one of the largest known land predators and is estimated to have had the strongest bite among all terrestrial animals. However, while T. rex was likely an apex predator, it might have also been a scavenger. To this day, the debate about whether he was purely a hunter of also scavenged is one of the most heated in the world of paleontology.

From here on, we will focus on a genus of dinosaurs instead of individual species, but we thought we’d give T. rex a category of its own.


The Stegosaur was an imposing creature, although its back spines were probably not as menacing as you might think. Image credits: Parker West.

Stegosaurus is a much older dinosaur than the Tyrannosaurus rex. So you can get an idea, the T. rex lived closer to the current day, than to the days of the Stegosaur — so those drawings of T. rex fighting a stegosaur are rubbish and have no geological truth to them. But if through some miracle you happened to see a stegosaur from some 150 million years ago, it would be a sight to behold.

Stegosaurs were large and heavily built herbivores. They had rounded backs and spiky tails which they likely held high in the air. The tails were most likely used for defense against predators, but contrary to popular belief, their recognizable back plates probably served a different purpose: thermoregulation. It was traditionally believed that these plates also served a defense purpose, but more recent research suggests that they were heavily vascularized, which means they were good for regulating the dinosaur’s temperature (they might have also been used for mating displays).


Triceratops horridus, a ceratopsian from the Late Cretaceous of North America, pencil drawing by Nobu Tomura.

Unlike the Stegosaur, the Triceratops was actually contemporary with the T. rex, so the two might have encountered each other. Alas, one can only imagine what impression the first Triceratops skull made on its discoverers. A massive, tank-like dinosaur boasting three devil-like horns on its armored head must have been quite the sight. However, while the Triceratops was probably not the most gentle of dinosaurs (fossil findings suggest that it regularly engaged in fights with predators and other members of its species), it was still an herbivore.

The Triceratops is one of the last known true dinosaurs, becoming extict 66 million years ago. Its name literally means “three-horned-face”. Its sturdy, robust body meant not only that the Triceratops was not an easy prey — but also that many examples have been preserved as fossils, allowing paleontologists to study the species in relative detail. Its fossils are among the most common dinosaur fossils in the late Cretaceous.


 Artistic restoration of Velociraptor mongoliensis. Not what you’d expect, eh? Image credits: Fred Wierum.

Velociraptor was not nearly as impressive as the other dinosaurs we’ve seen so far, and it was also not contemporary with T. rex — it lived just a few million years before T. rex emerged. Velociraptors were dog-sized dinosaurs, part of a family called dromaeosaurid. The largest velociraptors measured 2.07 m (6.8 ft) long, 0.5 m (1.6 ft) tall. Unlike what Jurassic Park shows you, Velociraptors were covered in feathers (or, at the very least, furry feathery coats). They were probably warm-blooded, at least to some degree.

In one of the most remarkable fossils ever discovered, a Velociraptor is found fighting a Protoceratops andrewsi, in a distinct example of predatory behavior. Also contrary to popular belief, there is no evidence that the Velociraptor hunted cooperatively (though recent findings have shown that they moved around as a group — at least sometimes). The pack-hunting hypothesis is still uncertain.

When did dinosaurs live?

Dinosaurs lived in a period called the Mesozoic. The Mesozoic is split into three large periods: the Triassic, the Jurassic, and the Cretaceous. Here is an image showing when some of them used to live.


Spinosaurus aegipticus, boasting the spinal structure from which its name derives. Image credits: Bogdanov, modified by Matt Martyniuk.

Spinosaurus was among the largest of all known carnivorous dinosaurs, nearly as large as or even larger than Tyrannosaurus. It lived around 100 million years ago, in the early to mid-Cretaceous. Among its many notable features, Spinosaurus also featured massive neural spines on its back — from which its name also derives. The exact purpose of these spines is still a matter of debate, though as with the Stegosaur, they were more likely used for thermoregulation and display than for defense.

For a long time, it was thought that Spinosaurus feasted on fish almost exclusively, as its elongated jaws, raised nostrils, and conical teeth suggest. However, more recent findings (including a fossil which contained bones of another dinosaur in its belly) suggest that Spinosaurus was likely to have been a generalized and opportunistic predator, feeding on anything its size allowed it to hunt.


Allosaurus fragilis, an allosaur from the Late Jurassic of North America, pencil drawing by Nobu Tomura

Allosaurus means “different lizard” — a name that alludes to its concave vertebrae, which at the time of its discovery was unique. Allosaurus was a large predator, somewhat like the Tyrannosaur. It measured over 9.5 metres (31 ft) in length, though some partial findings suggest that it might have grown way beyond that. However, unlike the Tyrannosaur, the Allosaurus might have hunted in packs (still under debate), making it one of the fiercest predators of its time.

Like many other predator dinosaurs (as well as both ancient and modern crocodiles), Allosaurus constantly grew, shed and replaced its teeth. Even if it hunted in packs, Allosaurus was more than capable of hunting prey on its own, several findings suggest.


Archaeopteryx is regarded as one of the most important fossils ever discovered. Here, a representation of what it may have looked like. Image credits: Pedro José Salas Fontelles.

Archaeopteryx is a genus of bird-like dinosaurs considered to be a transitional species between non-avian featured dinosaurs and modern birds. The name comes from the Greek archaios, which means “ancient”, and pteryx, which means “feather”. It is one of the most significant fossils ever discovered. It shared clear similarities with birds (such as small size, broad wings, and a presumed ability to fly or glide), but had strong dinosaur features: jaws with sharp teeth (instead of a beak), three fingers with claws, as well as a long, bony tail.

Archaeopteryx was not a large creature. It was similar in size to a magpie, and the largest individuals might have reached the size of a crow.


Samuel Griswold Goodrich: Illustrated Natural History of the Animal Kingdom, 1859. Today, paleontologists believe Megalosaurus was more likely bipedal.

Megalosaurus is truly worth the title of “giant lizard”, as its name implies. It was a large, meat-eating dinosaur from the middle Jurassic and is quite possibly the first dinosaur ever described properly in the scientific literature. Early naturalists considered it to be a gigantic 20-meter (65-foot) lizard, although more recent studies have found it to be probably in the 6-meter range (20 feet).

Megalosaurus may have hunted stegosaurs, iguanodons, or even sauropods. It was probably bipedal, although the earliest reconstructions depict it as 4-legged. However, although this dinosaur has been known for a long time, it is still not properly understood. Its skull shape, in particular, is not known.


Diplodocus longus. Image credits: Dmitry Bogdanov.

Diplodocus is one of the largest dinosaurs thus far discovered. Diplodocus carnegii, a Diplodocus species, is one of the longest dinosaurs conserved from a complete skeleton, but other individuals likely grew to even larger sizes. Diplodocus lived some 152 million years ago and like most sauropods, it featured a long neck and tail, and four sturdy legs. Its size and shape is so unusual that paleontologists aren’t even sure how sauropods were able to breathe.

They likely had an avian respiratory system (which is far more efficient than a reptilian or mammalian one). Diplodocus would have spent its days browsing on trees, ferns, and bushes, from low levels to around 4 meters high. However, reconstructions suggest that it could also use its tail as a prop, giving it a stable tripodal posture (on its hind legs and tail), allowing it to reach up to 11 meters high. Like giraffes, it is believed that Diplodocus developed such a long neck as a feeding advantage.


Possible appearance of an Ankylosaurus. Image credits: Mariana Ruiz Villarreal (LadyofHats).

Ankylosaurus is an armored dinosaur estimated to have been between 6 and 8 metres (20 and 26 ft) long. It walked on four legs, boasting a horned head that ended with a menacing beak, as well as a large club on the end of its tail.

Although Ankylosaurus has several striking features, its tail is probably the most interesting. Researchers believed it was actively used as a defensive weapon and was likely possible of crushing the bones of its would-be attackers — which, at the end of the Cretaceous, could have measured the likes of the T-Rex. Ankylosaurus’ mouth suggests that it was an indiscriminate herbivore, feeding on whatever plants it could find lying around.


Brachiosaurus altithorax, a sauropod from the Late Jurassic of North America and Africa, pencil drawing by Nobu Tomura.

Brachiosaurus is another sauropod, like the Diplodocus. In 1903, paleontologist Elmer S. Riggs named the dinosaur Brachiosaurus altithorax — with the name Brachiosaurus being Greek for “arm lizard”, and altithorax being Greek for “deep chest”.

The Brachiosaurus also had a bird-like breathing system, with air sacs pumping air. But Brachiosaurus was also atypical in some regards — for instance, it had long forelimbs (longer than its hind limbs), resulting in a steeply inclined trunk.


Image credits: Nobu Tomura.

Iguanodon is another emblematic dinosaur. Iguanodon were large, bulky herbivores, but they featured prehensile fingers with which they foraged for food, as well as large thumb spikes, which were probably used to defend against predators. The spike would have been used as a close-quarter stiletto-like weapon against predators, although a more benign explanation would be that it was used to break into seeds and fruits.

Given its well-developed jaws, it’s not clear what Iguanodon ate, although, given its size, it was probably a dominant herbivore. Remarkably, Iguanodon may have been bipedal in its early age, but became more quadrupedal as it got older and heavier.


Sketch of the hadrosaurid Parasaurolophus in tetrapod or quadrupedal pose, anatomically correct. Image credits: Tim Bekaert.

Parasaurolophus (whose name means “near crested lizard”) might not have the most famous name — but its look is definitely recognizable. Parasaurolophus was also a hadrosaurid, but its crest provides a notable difference to other species.

It’s not clear what role the crest served. It may have been purely sexual display, or may have served for thermoregulation, or even acoustic resonance. Most likely, it served quite a combination of purposes, making it a unique feature, even in the diverse world of dinosaurs.


This hadrosaurus does not approve of your behavior. Image credits: Audrey M / Wikipedia.

Hadrosaurus has a pretty self-explanatory name: hadros means “bulky” or “large” and sauros means “lizard”. As you may have guessed, Hadrosaurus is a large, bulky lizard — a very common trait in the dinosaur herbivores. Hadrosaurus foulkii, the only species in this genus, is known from a single specimen consisting of much of the skeleton and parts of the skull.

Hadrosaurus has traditionally served as the basis for a rather large subfamily called Hadrosaurinae, which was seen as a group of largely crestless group of hadrosaurs. However, recent studies have shown Hadrosaurs to be more primitive than their relatives, and the name Hadrosaurinae was restricted. That’s probably why it looks so judgy in the reconstruction above.

These are just a few of the countless dinosaurs that ruled the Mesozoic (not only the Jurassic!), from 233 million years ago down to the very present.

Wait. Does that mean dinosaurs are still alive? Absolutely! Birds are modern feathered dinosaurs, and it’s a remarkable example of how much a group of animals can change in geologic time.