"Terrible meat-eating lizards"
They roamed the Earth from about 240 to 65 million
years ago. They were a group of reptiles (cold-blooded animals
who had a backbone), with scaly skin, and they laid eggs. They
were first called "dinosaurs" in 1841 by Dr Richard
Owen - the word is Greek and means "terrible lizard".
And some of them had deadly, slashing teeth and claws which they
used to kill, and eat other reptiles.
These were the carnivores and they loved their
What's for dinner - meat, veg or both?
Carnivores were predators, hunting, killing and devouring
other weaker or smaller animals, including other dinosaurs, but
particularly their prey became the more gentle, peaceful herbivores,
or plant-eaters. There was also a third group of dinosaurs which,
like the human beings who were to succeed them many millions of
years later, were both meat-eating and plant-eating. These were
The Age of Dinosaurs began in the Triassic period
(248-213 million years ago). The first-known dinosaurs, in the
late Middle Triassic period, evolved from arabbit-sized creature.
By the end of this period, meat-eating dinos were as heavy as
From two legs to four
From the early predatory dinosaurs came plant-eaters
and from small bipedal (two-legged) herbivores emerged four-legged
creatures as big as a bus.
In the Jurassic Period (213-144 million years ago
- the name comes from the Jura Mountain rocks of France and Switzerland),
new, enormous dinosaurs emerged. Herbivores were the prey of
megalosaurids, allosaurids and other huge sharp-fanged predators.
In the last, longest Age (144-65 million years ago),
toothless birdlike dinosaurs emerged. Tyrannosaurids, the heaviest
land predators, were ranged against new, powerful plant-eaters.
At the end of this Age, dinosaurs became extinct.
All meat-eating dinosaurs were theropods -
literally "beast feet". Theropods existed from
the Upper Triassic to the Upper Cretaceous Ages (190-65 million
years ago). Some dinosaurs who were theropods belonged to a group
What Carnies were like
Carnosaurs - or Carnosauria - were large, flesh-eating,
saurischian (lizard-hipped) dinos, ranging in length from 6.1
m (20 ft) to 15.2 m (50 ft) and weighing up to about 6.4 tonnes.
Another way of putting it is: they were very, very big. They
were also very successful as a group - you could say they were
a kind of Prehistoric Jet Set - and their fossils have been discovered
throughout the world.
So what did they look like?
Typical carnosaurs, such as Tyrannosaurus
and Allosaurus, had large heads, short muscular
necks, powerful hind legs (they were bipedal, meaning they walked
on two of their "beast feet") and stiff, heavy tails
to aid balance.
Meat-eaters who swallowed vegetarians?
All in all, carnies were the most formidable of all
predatory dinosaurs. And they particularly hunted herbivores (plant-eaters).
The carnosaurs possessed the kind of jaws that could have swallowed
a human whole, and they had lots and lots of curved, serrated
teeth up to 18 cm (7 in) long for ripping flesh from their prey.
The huge "sailing" Spinosaurus
Some carnosaurs had unusual features; for example,
Spinosaurus - at 15.2 m (50 ft) the largest carnosaur
yet discovered - had a 1.5 m (5 ft) tall "sail" along
its back. The exact function of this sail is not known. It may
have been used to regulate body temperature, attract mates, or
frighten other dinosaurs during territorial battles.
Another unusual carnosaur was Baryonyx,
whose long neck, crocodile-like jaws with many sharp teeth, and
relatively long forelimbs with large hooked claws were probably
adapted for hunting fish.
The brainiest of the breed
Theropods were the brainiest of all dinosaurs and
the brainiest group of all theropods was the coelurosaurs.
In contrast with carnosaurs, they were small, slightly built,
nimble and fast-running predators with small heads - whose narrow
jaws were lined with small, sharp teeth - long flexible necks
and long arms with sharply-taloned grasping hands.
Coelurosaur means "hollow lizard" and they
were probably the most successful of the lizard-hipped dinos.
Some coelurosaurs were the fiercest of predators, including a
species considered to be the ancestor of the first true bird.
Unfortunately, although coelurosaurs must have been
quite abundant throughout the 140 million year reign of the dinosaurs,
the fact that they were both small and slender has reduced their
fossil evidence. Small animal carcasses tend to rot quickly and
their skeletal remains are liable to be scavenged and scattered,
or completely destroyed.
An odd mixture
The coelurosaurs were an odd mixture of small, nifty
theropods, who may not have been close relatives but shared physical
characteristics. They were all fast runners, hunting for mammals
and insects. Coelurosaurs were the "clean-up squad",
finishing off food after carnosaurs had had their fill.
One of the most active predators of the coelurosaur
clan was Ornitholestes ("bird robber").
About 2 m (6.5 ft) long, Orni fed on small animals like lizards,
frogs and early mammals. It had strong jaws and powerful grasping
hands. and may have captured early birds for food.
Among the earliest coelurosaurs was Coelophysis
("Hollow Form"), another small, agile dinosaur
1 m (3 ft) tall, with a wedge-shaped head and sharp, serrated
teeth, who chased after its prey, grabbing small lizards in hands
set free by its upright posture. Fossils reveal that the species'
prey may have included its own babies!
When did they arrive?
Dinosaurs first appeared 230 million years ago, at
the beginning of the Late Triassic Age. The earliest-known were
the carnivorous (flesh-eating) herrerasaurids and staurikosaurids,
such as Herrerasaurus and Staurikosaurus.
Too primitive to be saurischian (lizard-hipped) or
ornithischian (bird-hipped), Herrerasaurus was a
two-legged flesh-eater 3 m (10 ft) long, with sharp teeth, short,
birdlike, folding arms, longer thighs than shins, four-toed feet
and hip bones with saurischian and ornithischian features. Fossils
have been found in northwest Argentina. Herrerasuria may have
been the stock that gave rise to all other dinosaurs.
"Southern Cross lizard"
another primitive dinosaur, a speedy, lightly built two-legged
carnivore 2 m (6 ft 6 in) long and weighing 30 kg (66 lb), with
a large head, sharp teeth, short arms, long legs and tail, five
toes and fingers, and only two vertebrae joining spine to hips.
What was their prey?
Life on Earth was originally water-based until amphibians
living on land and in water ("amphibious" means "having
a double life") evolved from meat-eating fishes. Only after
reptiles conquered the land did vertebrates begin eating plants.
And meat-eating dinosaurs were there already,
waiting for them!
Reptile eats reptile
In the Triassic Age, many sprawling reptiles and
amphibians were killed off by thecodonts, reptiles of the
archosaur group. Thecodonts died out, many killed by the
earliest dinosaurs such as herresaurids and staurikosaurids.
Dinosaur eats dinosaur
Small predators chased lizards, seizing them in sharp-clawed hands, swallowing them head first. Others roamed in packs, creeping up on big plant-eaters then killing them with a sudden rush. Dinos ate each other, theropods striking with their fangs and sharp toe and finger claws. The toothless variety made do with
insects or digging up and eating other dinosaurs'
So what was so special about T.rex?
Tyrannosaurus was the
biggest and strongest meat-eating animal ever - nearly as tall
as a double-storey house. Although it was very heavy, scientists
believe it could sprint over short distances to catch slow-moving
Family ties of the "tyrant lizard"
Tyrannosaurus rex ("tyrant
lizard") belonged to the Tyrannosaurids, a closely knit group
of Late Cretaceous (65 million years ago) theropods. Its closest
relatives were Daspletosaurus and Tarbosaurus, both
very similar types. One further relative is Albertosaurus
- though separated slightly from its cousins because of its light
When it lived and where
Remains have been found in Late Cretaceous rocks
in Colorado, Montana, New Mexico, South Dakota, Wyoming, China
and Mongolia. It lived for a comparatively short period - in
dino terms - 70-64 million years ago. But in that mere 6 million
years tyrannosaurids established themselves as the main predators.
Indeed T. rex is one of the last known dinosaurs.
How big was big?
With a length of 14 m (46 ft) and a height of 5.6
m (18.5 ft), T. Rex was one and a half times as big as its closest
relative, Daspletosaurus, whose length was 9 m (29.5 ft).
Weighing 5 tons it could run at a speed of 15 to 25 mph and had
a life span of up to 200 years.
T. rex had a massive skull with powerful jaws that held serrated 18 cm (7 in) long teeth which could be compared in length and shape to a set of steak knives. The tyrannosaurids were not recognised as a distinct group until 1906, shortly after the first reasonably complete skeleton of Tyrannosaurus was discovered in Montana in 1902. But 50 years earlier in the mid-nineteenth century. Joseph Leidy, the pioneering palaeontologist, described the set of teeth also collected in Montana, and later identified as belonging to T. rex, as Deinodon horridus - "horrifying, terrible tooth".
With its enormous head and barrel-shaped body, T.
rex is the most widely recognized of the ancient predators.
It walked upright on long, powerful hind legs with three-taloned
feet. Its small forearms had tiny, two-clawed hands. Standing
it would have been tall enough to peek into a second-storey window.
Tail up or down?
For many years after its discovery, Tyrannosaurus
rex was incorrectly displayed as having its long tail dragging
on the ground. It is now thought that the correct position is
more likely to be: tail out, balanced in the air.
"Dem bones, dem bones, dem dry bones"
Because of its massive size (14 m (46 ft) long) and
weight (7 tons) , Tyrannosaurus' skeleton is an amazing
balance between the need to bear this massive weight and to run
around to catch food. Its massive skull, built to withstand impact,
is supported by a stout neck. The backbones acted like a massive
With these hands
The arms and hands of Tyrannosaurus are among
its most bizarre features. The forelimbs of carnosaurs tend to
be relatively short when compared with those of the more lightly
built coelurosaurs. In T. rex and tyrannosaurids generally this
trend seems to be taken to a ridiculous extreme. The shoulderbone
is moderately large, but the arm is minute and ends in a small
What was the claw for?
There are various theories about T. rex's two-clawed
hand. One suggestion is that the hand might have been used as
a kind of grappling hook during mating, or to anchor the front
of the body as the animal tried to raise itself after resting
on the ground.
Footloose and fancy free
T. rex's feet are much stronger than its hands since
the back legs take the animal's weight. The broad short feet
have three forward-pointing toes ending in sharp, curved claws.
Born to kill
T. rex was a ferocious hunter, able to charge with
great speed. Following and ambushing herds of plant-eaters, it
was able to judge distances when attacking its prey with the help
of its forward-facing eyes. Probably using its tiny arms to push
itself upright after it had been lying down, swinging its muscular
tail, it moved in for the kill, lunging forward, massive jaws
open, throwing its head up and roaring.
Just one bite
T. rex could kill with one crushing bite of its
massive steak-knife teeth, twisting its powerful neck, ripping
flesh from its prey, pinning the carcass to the ground with its
large birdlike feet. With its huge appetite, it could have easily
eaten its own weight in meat every week and probably stole the
kills of other animals to survive. Tyrannosaurus' skeleton
shows broken bones, leading experts to believe that it engaged
in a lot of fights.
The laid-back lifestyle of Albertosaurus
Unlike its tyrannosaurid relative T. rex, Albertosaurus
was a very slow-moving creature of sluggish habits, who would
lie prone on the ground for long periods. When driven by hunger,
Albertosaurus would raise itself to its feet and slowly
pace about in search of food, relying mainly upon scavenging the
carcasses of dead animals.
T, rex: quick mover - but short distances only
In contrast with its lazy cousin, Tyrannosaurus
was a dynamic animal. In spite of its great weight, it was not
a slow, lumbering creature. Like the rhinoceros, which also possessed
pillar-like legs to support its immense bodyweight, it could run
extremely fast but only over short distances. It's hard to imagine
a six-ton tyrannosaurid chasing a hadrosaurid at speed for several
kilometres. What's more likely is that tyrannosaurids were lurking
predators waiting in ambush for their prey and catching them after
a short chase.
Triceratops - the three-horned rhino beast
In spite of its overwhelming power and ferocity,
T. rex didn't always get its own way. Some of its more difficult
prey, like Triceratops, could inflict nasty injuries.
One of the strongest dinosaurs, Tricer's massive horned skull
and over 6 m (nearly 21 ft) long, barrel-like body were built
to withstand attack from the fiercest predator. It could charge
at more than 25 km/h (15 mph) against an attacking meat-eater.
Tricer's enormous head made up almost one-third of
its overall length. The head was armed with long, sharp horns
on the brow and nose, which could be used as fearsome weapons
if they didn't scare off an attacker. The head-frill was edged
with bony lumps, protecting the dinosaur's powerful neck.
Triceratops' thick skull
and strongly built neck and hips helped it to withstand the impact
of crashing into an attacker or locking horns with a rival.
Euoplocephalus - the armoured dino
Another worthy foe was Euoplocephalus ("well-armoured
head") of the Ankylosauridae family, a four-legged
armoured dinosaur up to 7 m (23 ft) long and weighing about 2
tons, with a broad beaked head and massive limbs. Like many other
plated dinosaurs, Euoplocephalus had a leathery skin studded
with bony lumps and bumps. Its other formidable weapon was a
spiked bony club at the end of its raised tail.
Edmontonia - spiky armoured plant-eater
Edmontonia, of the Nodosauridae
family, could also defend itself against T. rex. A large, four-legged
plant-eater, 7 m (23 ft) long, it had a tough armour of bony plates
and fierce spikes.
Pachycephalosaurus - "Thick-headed Lizard"
This was the largest bone-headed dinosaur: a two-legged
plant-eater 4.6 m (15 ft) long with a high-domed braincase 25
cm (10 in) thick, low spiky snout and sharp knobs at the back
of the head, making it look like a crash helmet.
Tyrannosaurus meets Triceratops
Sometimes, even the mighty T.rex can meet its match.
Triceratops is well-protected against the
fierce predators, such as Tyrannosaurus , that track the
herds of plant-eaters across the great plain. Triceratops'
giant, bony frill also makes its head look huge and frightening
to deter any prowling carnivore or meat-eater.
Triceratops has long,
sharp horns on its forehead and snout. In addition, the dinosaur
has specially strengthened bones on its neck and hip area and
on the roof of its skull to withstand great shocks if it charges
into an attacker.
The monster attacks
A hungry T. rex spots a Triceratops, feeding
away from its herd. The meat-eater rushes at its prey, hoping
to knock it down. It will try to wound Triceratops with
one fatal bite from its dagger-like teeth. Tricer shakes its
head, bellows, and lunges towards its attacker
Moving in a trice
As Triceratops rises from the ground, its long back legs push its hips upwards. Huge muscles support Tricer's great 6-tonne (6 ton) body over its front and rear legs. Its hip bones take the strain of its heavy body weight. Breaking into a run, perhaps as fast as 25 km/h (over 15 mph), it charges forward, trying to stab
Tyrannosaurus' belly with
its horns. If it succeeds, Triceratops may escape from
death - this time.
Standing its ground
Tricer may look a little like a rhinoceros - but
it's twice the size and a reptile, not a mammal, though it may
have had similar ways of defending itself. Pawing the ground,
its legs kicking up a cloud of dust to confuse its attacker, it
hisses at T. rex, looking for a way to escape the terrible hunter's
razor-sharp, slashing teeth. But Tyrannosaurus is growing tired
and may decide to give up and hunt a weaker animal.
Some people think Tyrannosaurus may not have
been so much the grand predator of the dinosaurs as the grand
scavenger. Because of its leg joints and the position of its
feet, the argument goes, it could only take very short steps,
moving at about 5 km/h (3 mph), and therefore could hardly have
chased and fought with the other animals. This, of course, contradicts
the view that T. rex attacked in short fast bursts.
Tyrannosaurus' 15 cm (6
in) long teeth were saw-edged and ideal for slicing up meat, but
they were also very thin and could well have been broken in combat.
So it is possible that T. rex may partly at least have scavenged
for food, eating the bodies of dead animals which had been killed
by other predators. After it had discovered a large plant-eater's
carcass, T. rex squatted down beside it, ready to eat up its dinner.
Whether Tyrannosaurus scavenged or hunted,
the prey would have been rapidly torn apart. Its jaws, armed
with those large serrated teeth, would have sliced through the
skin and flesh of the carcass. Violent twisting and tugging of
the head, aided by T. rex's powerful neck and legs, would have
torn the most powerful of sinews, so that great chunks of flesh
and bone could have been swallowed whole.
Another theory is that, as tyrannosaurid skulls are
heavily reinforced, they may have attacked their prey by running
into it jaws agape, the shock of such a collision being absorbed
by the skull bones.
And those tiny arms and hands?
The minute size of T. rex's forelimbs is another
puzzle. One explanation is that they were used as props to help
it rise from a prone position. And after a long siesta it would
climb to its feet, ready for the next meal
The demon kangaroo dino
It was quite unlike other dinosaurs, with its long
upcurved skull, slender, compact proportions, sharp teeth and
great sickle claws. Velociraptor was fast, smart and a
highly effective hunter which was well-equipped for attack and
could beat a hasty retreat from larger predators. It had large
eyes on each side of its triangular-shaped head and looked a little
like a kangaroo.
A ferocious little beast
The ferocious raptor had long, clawed fingers and
toes, with hands that could grasp and clutch its victim. Known
for its strength and speed, its size and shape were perfectly
designed to capture swift, lightweight prey. Scientists know
it could also handle larger animals because of its wide jaws.
Its most distinguishing characteristic was the sickle-like claw
on the second toe of each hind foot, just right for slashing meat.
Pound for pound it was among the most powerful known predators.
Family ties: Is it a bird? No, it's a raptor
in the Late Cretaceous period, 80 million years ago. It belonged
to the family of theropods known as Dromaeosaurs. However, to
confuse matters, in recent years it has also been classified as
belonging to another related family - that of the feathered, winged
Archaeopteryx, believed to be the direct ancestors of the
first birds. Not that raptors had feathers, nor could they fly,
but they share many characteristics of primitive birds. And the
word raptor itself means "bird of prey".
"That doesn't look very scary - more like a six-foot turkey"
If you've seen Jurassic Park, remember
the young boy whose sceptical attitude is replaced by one of terror
and awe as the palaeontologist describes the pack-hunting methods
of attack of the little creature on the TV monitor? Yes, that
Where's the evidence?
Remains have been found in North America, China,
Mongolia and Russia.
Anyone for sickle claws?
The most dazzling feature of Velociraptor
is the tremendous sickle claws, far larger than in any other known
predator. They can be compared to the sabre teeth of some extinct
cats, weapons of power way beyond what was normal for animals
of their size. Among theropods only Tyrannosaurus, with
its huge skull length, could equal velociraptor in total power
relative to weight. The claws enabled them to be big-game hunters,
capable of felling animals much bigger than themselves.
Velociraptor antirrhopus - fantasy beast
Found in Montana and Wyoming, V. antirrhopus is
3 m (10 ft) long with a skull length of 332 mm (13 in), femur
length of 284 mm (11 in) and weighing 45 kg (86 lb) (though the
largest example was 3.3 m (11 ft) long with a 45 cm (1ft 6 in)
head), its long, low, streamlined skull and fantastic array of
claws have turned it into an extraordinary fantasy creature -
except, of course, that it existed!
V. mongoliensis - locked in combat
The most advanced species of Velociraptor,
it has a greatly elongated snout. Found in Mongolia, it was 2
m (6.5) long with a skull length of 190 mm (7.5 in) and femur
length of 200 mm (8 in). Amazingly, remains show it locked in
combat with a small horned dinosaur, the raptor's hand still gripped
in the protoceratopsid's beak!
A steering tail
A fast runner, raptor's long, stiff, slender, rudder-like
tail enabled efficient steering. The tail end, marked by two
bands of long, ossified rods, exerted stiff whip-action balance
for hard manouevres, while the first few vertebrae behind the
hips could bend 90 degrees upwards. It was thus both flexible
A bit of a bird
Birds have unique "saddle-shaped" necks,
which can be seen in Velociraptor, with its lightly built
upturned skull and curved neck. So successful was raptor's design
that its form hardly changed for 50 million years - a rare achievement.
Snapping jaws and slashing claws
Velociraptor had vicious
jaws that would bite the flesh of its victims, sometimes while
they were still alive! It could do this because its main weapon
was the slashing claw on its hind foot. The jaws were secondary
weapons. It killed by deeply raking the prey's limbs or belly
with the sickle claws on the second toe of each hind foot, probably
disembowelling the victim. Both claws were used in tandem, to
double the effect.
The raptor's prey
Velociraptor was a Prehistoric
"Jack the Ripper". The victims of its predatory raids
of terror were generally larger plant-eating dinosaurs, like Tenontosaurus
("sinew lizard"). This bipedal/quadropedal (both
two- and four-footed) beast about 21 ft (6.5 m) long, had a deep
head, toothless beak, broad five-fingered hands and four-toed
feet, with long arms and a strong deep tail which perhaps it swung
in vain to defend itself against raptor's attack.
How raptor was discovered
The original specimens of Velociraptor were
collected in the early 1920s by an American expedition to the
Gobi Desert in Mongolia. It wasn't clear what kind of dinosaur
it was until the discovery of Dienonychus, a similar
predator, in the 1960s showed the powerful jaws and great hunting
claw on the foot in detail.
Even "Plunderer" was vulnerable
In 1971 researchers made a remarkable fossil find:
the skeleton of a Velociraptor that had died while attacking
a horned dinosaur called Protoceratops ("first horned
face"). This Late Cretaceous four-legged plant-eater was
1.8 m (6 ft) long with big head, parrotlike beak, shearing cheek
teeth, broad bony neck frill, thickened bones above the eyes and
snout and a bulky body.
Tit for tat - horns for claws
Apparently the predator killed its prey by disembowelling
it. At the same time the Protoceratops, with its armoured
head, somehow impaled the raptor. And so the two died - intertwined
THE RAPTORS ARRIVE
A sunny day in Montana, 80 million years BC
In the humid plains of Montana in the Lower Cretaceous
period, a Tenontosaurus is grazing in a clearing, having
left the safety of the trees to feed on the plants that grow on
this sunny spot. It is a rash move for it has made the plant-feeder
conspicuous and vulnerable to attack from predators.
The raptor appears, moving lightly like a bird, bobbing
its head. By instinct, Tenontosaurus freezes, genetically
programmed to believe that if it doesn't move the raptor won't
be able to spot it. But unlike T. rex, whose visual acuity is
based on movement and who will lose its prey if it doesn't move,
Velociraptor keeps Tenontosaurus in its sights.
For long long seconds the two creatures stare at
each other in silence and still without moving. And that's when
the attack comes. Where Tenontosaurus is least expecting
Slash from the side
The attack comes not from the front, but from
even see the other two raptors. Velociraptors hunt in
packs, using co-ordinated attack patterns. They slash at Tenontosaurus
with their six-inch retractable sickle claws, wounding its
flanks and soft underbelly, using their stiff tails to balance
themselves as they turn and turn again, slashing with demonic
Tenontosaurus can bite
with its beak and kick hard. It's also a fair runner, but its
power is no more than that of a big horse and no match for the
raptors' concerted attack. Still alive, Tenontosaurus
staggers and falls as the Velociraptors start to eat it,
disembowelling their victim.
And all this could actually have happened
The main Velociraptor quarry in Montana includes
pieces of a Tenontosaurus which the Velociraptors may
have been feeding upon when they all died together.
The mysterious case of Archaeopteryx's wishbone
In 1861 fossil hunters came upon the bones of a perfectly
preserved Late Jurassic creature in a German quarry. This reptile
had died 150 million years ago. But the mud into which it fell
hardened before the skeleton could be destroyed by natural decomposition
or scavengers. When they inspected it closely, scientists made
an extraordinary discovery: the reptile was covered with
Dinos with wings?
The tiny feathered dinosaur was 0.9 m (3 ft) long,
had thin, fine-boned legs, long, delicate toes and slim jaws with
short teeth. Its feathers lay along its slender arms and the
long bones of its tail. It was named Archaeopteryx ("Ancient
Feather") and it was soon found to share yet more characteristics
with birds. Most extraordinary of all, Archaeopteryx had
what was clearly a wishbone, just like those to be found in the
collar bones of all birds, and which no other animals have.
But what's this to do with Velociraptor?
Well, for the next hundred years scientists debated
about the link between dinosaurs and birds. The doubters argued
that whereas Archaeopteryx's wishbone had clearly evolved
from a collar bone, the coelurosaurs - which were the dinos that
resembled Archaeopteryx most closely - didn't even have
But Velociraptor did!
In the 1970s palaeontologists made some startling
fossil discoveries. They found that Velociraptor and some
other coelurosaurs did have collarbones that could well have developed
into Archaeopteryx's wishbone. Scientists now generally
agree that Archaeopteryx is related to Velociraptor
and some coelurosaurs, and the debate has moved on to such
questions as the function of Archaeopteryx's primitive
wings, why feather first evolved, how skilful they were as fliers
and where they lived.
Little Compy - the miniature dino
one of the smallest dinosaurs ever found, being roughly the size
of a guinea hen. With its long legs and tail, it was able to
run extremely fast.
Not so much a cannibal, more of a lizard-eater
The Compsognathus resembled a wingless bird,
with its narrow jaws and sharp teeth. These razor-sharp teeth
show that it may have eaten small vertebrates as well as insects.
One well-preserved skeleton was found with a lizard in its stomach.
With its long neck and flexible forearms, Compsognathus was
a light, fast predator. The little Compy had a small head, low
skull and massive upper leg bones. Its feet were birdlike with
three-fingered claws. It had a long, whiplike tail and a long,
narrow mouth. Its eyes were positioned back along the sides of
its head. Compy proved to be an agile, crafty hunter.
One of the smallest of the small
Compsognathus longpipes (meaning
"Pretty Jaw" or "Elegant Jaw") was a small
theropod, one of a diverse group of lightweight, predatory saurischian
(lizard-hipped) dinosaurs that were widespread from Late Triassic
to Late Cretaceous times (231-65 million years ago). Compy was
one of the smallest, at about 70 cm (28 in) long, but even the
largest small theropod, Coelophysis, was only 3
m (10 ft) long.
The perfect specimen
Closely related to Coelurus, it lived
at about the same time. Only three specimens of Compsognathus
have been found - in south-east France and Bavaria. A single
complete skeleton was found in Germany in 1861, pressed in lithographic
limestone. A fascinating fact is that this was one of the most
completely preserved sets of dinosaur bones ever found.
Compy had a light, sharp-snouted skull. Large open
spaces allowed its muscles to move. The eye sockets were large
and this dinosaur probably had large eyes to help it find and
chase its prey.
Not just another turkey
One of the smallest-known dinosaurs, Compsognathus
longipes was about the size of a turkey, measuring only 70-140
cm (28-54 in) in
length and weighing 3 kg (6.5 lbs); its average skull length was
76 mm (3 in); femur length 67 mm (2.6 in); and hip height 0.21
m (8.3 in) .
Such a small, agile hunter needed sharp teeth to
deal with its prey when caught. Compy had about 68 small, widely
spaced, delicately curved teeth in its jaws. The front teeth
were more conical than those behind and lacked serrations. The
front lower teeth radiated from one another like the spokes of
a wheel. All this indicated that this house-cat-sized theropod
was a full-time small-game hunter; the semiconical teeth couldn't
do much damage to a big victim. This isn't surprising since its
home was a Jurassic European group of small semi-arid islands
upon which only small vertebrates (like lizards) lived.
Where did Compy live?
Compy probably lived on the unforested shores of
lakes and lagoons - its footprints have been found in sand and
mud. This was a popular place to live because there was plenty
of water and vegetation, and sandy soil in which to lay their
eggs. Compy may also have eaten scraps from the water. It was
alert with good senses and it needed them in a world full of bigger
Compy had large eyes to look out for and chase prey,
and to watch out for enemies. Its speed was useful for avoiding
predators. Despite this, it probably had a short lifespan, and
may have laid large clutches of eggs to ensure the survival of
Prehistoric heating shortage
If dinosaurs were warm-blooded, it is the small animals
like Compy that would have had difficulty finding enough food
to keep warm - the bigger dinosaurs seemed to fare much better!
The riddle of Compy's "death throe"
The single skeleton of Compsognathus longipes
found in 1861 was the first complete dinosaur skeleton ever
discovered. The skeleton is twisted backwards and some pieces
have been moved apart. The tail's lifted up; the head bent back
over the tail. This was considered an unnatural position, indicating
that Compy was in agony.
Did it die in its sleep?
In fact, when long-necked animals die, their neck
muscles and ligaments dry and shrink, causing the neck to curl
backwards. Gases from rotting part of the flesh of other parts
of the body may cause bones to move apart. Nearly all the bones
have been preserved, but almost half the tail's missing. Although
Compy's head has been turned upside down, the bones around the
brain have been fossilized. The back legs are still in place
on both sides of the pelvis, and the tiny, sharp toe bones have
More about that skeleton
Compy's skeleton, like that of Coelophysis and
Ornitholestes (both coelurusaurs), was lightly built: these
animals were comparatively small for dinosaurs and presumably
did not have serious weight-bearing problems. Its neck was long,
flexible and joined onto a compact body. The animal was bipedal
(two-legged) with strong, slender back legs and reduced, but still
useful, front legs. Compy's fingers were armed with strong claws
for grasping prey. Its tail was long, acting as a counterbalance
for the front of the body.
Windows in the skull
Compy's skull contained open spaces - windows. These
had two functions: they lightened the skull which aided Compy's
speed and mobility and they left extra room for the muscles which
opened and closed its jaws. These windows were: (a) nasal opening;
(b) antorbital opening; (c) orbit (for the eye); (d) upper temporal
opening; (e) lower temporal opening; (f) mandibular opening.
In the armoured skulls of such dinosaurs as Panoplosaurus these
holes were closed.
A diet of reptiles
The specimen of Compsognathus discovered in
1861, like of those of Coelophysis, had small bones inside
it, and it was thought that Compsognathus was also a cannibal.
It has now been shown that the bones belonged to a lizard, Bavarisaurus.
Looking for lizards
A two-legged runner, Compsognathus caught
fast-moving insects and small lizards. Its long back legs and
long four-toed feet were essential for providing the speed it
A glimpse at Compy's life
Time: 155 million years, BC
Place: island in
the Upper Jurassic lagoons of Germany
In lush undergrowth among tree-like cycads and stubby
palmlike cycadeoids, with gingkoes, ferns and tree ferns clothing
river banks in forest, two Compsognathus run through horsetail
thickets, chasing sphenodontid lizards and dragonflies. Above
them pterosaurs dart through the air, catching prey. An Archaeopteryx,
the first bird and Compy's close relative, squawks a descant over
the buzzing symphony of insect and reptile sounds.
Why only two fingers?
Compy had only two complete fingers on each hand.
The third finger was only one bone.
Scientists are stumped
Small arms like those found on Compy were not used
for walking or running. The two short-fingered hands may not
have been much use for grasping prey either. Scientists still
do not know what Compy did with its hands.
Who are Compy's descendants?
It is difficult to compare Compy with any living
animals. There are very few two-legged carnivores about - all
the two-legged ones are birds (like kestrels and eagles). But
they are not that similar to Compy. After all, Compy was a ground-living
dinosaur (it couldn't fly!) and had scaly skin, not feathers.
Dinos, birds and crocs
Although about 64 million years ago dinosaurs became
extinct, there are animals today that bear some relation to them.
Two surviving relatives of dinosaurs are birds and crocodiles.
Ancient ostrich without feathers?
It is believed that birds emerged from a common ancestor
during the Jurassic period, about 190-300 million years ago.
But it is more likely that birds evolved from two-legged dinosaurs,
like Compy, which could have been the ancestor of the ostrich,
looking very similar apart from its scaly skin, long tail and
Ancient case of mistaken identity
The first recorded skeleton of a feathered dinosaur
- Archaeopteryx - was incredibly similar to Compy. Its
bones have even been mistaken for Compsognathus' fossils.
They did differ - their hips varied and Arch had longer legs
to support its wings. Arch probably ran like Compy with short
bursts of flight to catch insects.
What made dinos fly?
It's easy to understand why dinosaurs took to the
air - it meant that they would have been safe from predators and
enabled them to travel long distances with ease in their quest
Separated at birth or just good friends?
For fast-moving dinosaurs like Compy, it was logical
they would eventually want to take off into the air. Compy's
limb bones resemble those of birds - the forelimbs with 3 digits
and hind limbs with 4 toes. Dinosaur ankles are also like those
of a bird, with heel bones fused to the shin bones. Dinosaurs
also had a skull with more holes in it than other reptiles - two
openings behind the eyes and one between the nose and mouth.
Birds have a version of this skull today. Dinos also show the
existence of blood vessels and air-sacs in their bones, just like
Next time you see a bird, imagine it with scales
instead of feathers, and arms and claws instead of wings. And
a long tail. Then increase its size massively and there you have
it - your very own Compsognathus in your back garden!
Palaeontology: looking for clues
Palaeontology is the study of the geological past.
Scientists have made maps to show the different ages of rocks.
Dino fossils are found throughout the world in 210-64 million-year-old
How are fossils made?
When most animals die, their remains are broken up
and destroyed by the weather and by other animals. Sometimes,
however, their bodies are washed into a river or lake and quickly
covered in sand and mud; in a desert the remains might be covered
by wind-blown sands. This is how some dinosaurs became preserved.
Permineralization - minerals reinforced the bones
Over millions of years more and more sand and mud piled on top of the remains. The sediments gradually turned into sandstone, limestone and shale, the soft parts of the dinosaurs' scaly skin lasted long enough to leave its impression in the fine mud, and fragile egg shells were also turned into fossils.
Petrification - turned to stone
The fossils discovered by scientists are different
from the dinosaurs' original remains. Chemicals have changed
them into stone, or they may have been crushed. Sometimes minerals
replaced the bone itself until the bone was turned to stone.
Different types of remains
Teeth: the hardest parts
of all, often surviving with little change at all
Moulds: certain minerals
dissolved some bones but left bone-shaped hollow fossils called
Casts: a mould that was
later filled by other minerals became a cast; some moulds or casts
even show a dinosaur's scaly skin
Trace fossils: other traces
left by dinosaurs, including:
Ichnites: fossil footprints,
left in lakeside mud that dried out in the sun; fossil trackways
show where dinos walked on two or four limbs, whether they trudged
or sprinted (fast runners' footprints would be far apart), and
travelled singly or in herds
Coprolites: these fossil
droppings are moulds showing the shape of the intestines
Ooliths: fossil eggs
The tools of the trade
Dinosaur discoveries are rare, often lying buried
in layers of rock until exposed on a hillside, a quarry or perhaps
a rocky beach. Only then can a team of experts go to work to
excavate fossil dinosaur. They use pick-axes and shovels
to clear away rock; hammers and sharp chisels to work close to
the bone without damaging it, and brushes to sweep away the dust.
Workers wear protective goggles to keep their eyes safe. Hard-hats
are essential near cliffs.
Protecting the fossils
Wet tissue paper is spread over the fossil to protect
the surface. Thick bandages or sacking are soaked in plaster
and spread over the paper. When this has hardened the fossil
is carefully turned over. Its other side is also covered in paper
and plaster bandage. When the plaster has hardened, the fossil,
wearing its "jacket", can then be lifted out.
Putting dinos together again
After the hard work of excavation, the precious fossils
are taken back to the laboratory for preparation, study and display.
They are removed from their protective jackets; then the remaining
rock or earth is cleaned away with chisels, delicate power-driven
tools and chemicals. The cleaned bones are then studied to understand
how they fitted together - and therefore how the dinosaur lived.
Tell-tale clues can be found on the bone surface: muscles sometimes
leave clear marks where they were attached.
Adding the flesh
It may take some time to work out how the bones fitted
together and missing bones may have to be modelled from plaster.
Skin impressions have sometimes been preserved to aid the model-maker,
but colour is a matter of guesswork.
A load of old bones
During the 19th century, when dinosaurs
had just been discovered, the sculptor Benjamin Waterhouse Hawkins
built models of dinosaurs first in Britain, then in America.
Dinosaur remains have been found all over Europe, but the fossilized skeletons tend to be less complete than elsewhere (with the notable exception of Comfy). The word "dinosaur" was first coined in England in 1841 to describe the three known giant reptiles at the time: Iguanodon ("Iguana Tooth"), a plant-eater found in great numbers; Megalosaurus ("Great Lizard"), a large heavily-built two-legged predator 9 m (30 ft) long and weighing a ton; and Hylaeosaurus ("Woodland Lizard"), a four-legged armoured plant-eater.
This part of the world has been popular with dinosaur
hunters since the mid-19th century. Famous finds include:
Tyrannosaurus, Diplodocus ("Double
Beam"), a long four-legged plant-eater; and Stegosaurus
("Roof Lizard"), the largest known plated dinosaur,
a four-legged plant-eater 9 m (30 ft) long. New dinosaur remains
are still being discovered here.
Important finds include the two-legged flesh-eater
Herrerasaurus, one of the earliest known dinosaurs,
who lived 230 million years ago.
This huge continent has been home to many different
kinds of dinosaurs. The oldest are found in the south; younger
dino remains are further north. Among the finds are: Spinosaurus
("Thorn Lizard"), an immense two-legged predator
with huge teeth and vast crocodile-like lower jaw.
Some of the most recent and exciting finds have been
made in Asia, including Tarbosaurus ("Alarming
Lizard"), a two-legged flesh-eater whose immense head contains
huge jaws armed with terrifying fangs. Fossilized dino bones
(once thought to belong to dragons!) are found all over China.
Many dinosaur remains, including dino eggs, have been discovered
in the Gobi Desert.
Not many dino fossils have been found: the most complete
dinosaur discovered here.was the plant-eating Muttaburrasaurus.
Only two dinosaurs have been excavated here so far,
in 1988 and 1889, but there may well be many dino fossils under
Antarctica's icy waters.
Before people understood how old the Earth was, they
entertained ideas about fossils that now seem very funny: they
were put there by the devil to confuse people; or they were the
remains of animals drowned in the Flood when Noah escaped in his
ark. The explanation nearest to the truth was the suggestion
that fossils were mistakes that God made while creating all the
and theories of extinction
About 65 million years ago dinosaurs, plesiosaurs,
pterosaurs and many other animals of land or sea became extinct.
Just why remains a mystery that many scientists have tried to
solve. Among the theories: dinos evolved such awkward bodies
that they couldn't move or breed; predatory dinos ate the rest
then starved; tiny mammals gobbled up dino eggs. But the most
likely explanations have been drastic global change or relatively
slow extinction as shifting continents, rising mountains and shrinking
seas helped new creatures evolve who outcompeted the old.