inos pl an t- ers auria pla m my uh uh t e us th m i, c nt ... · the eggs maiasaura feeds her...

ISBN 978 1 7418 3775 9DIN

OSAURIA

PLANT-E

ATERS

MAIASAURA was a duck-billeddinosaur (hadrosaur). It had along snout, a toothless

beak, and crests above its eyes.Inside its cheeks were many self-sharpening teeth, perfect forgrinding up plants, berries,leaves, and seeds. Its scaly skinwas covered with warts. Likeother hadrosaurs, it walkedsometimes on two legs, other timeson all fours. Its back legs were longerand stronger than the front ones. Its toeshad fleshy pads on their undersides.

Maiasaura was 30 ft (9 m)long and 10 ft (3 m) tall.

26

MaiasauraDINOSAUR ASTRONAUTMaiasaura means “good mother lizard.” Itwas so named because of the evidence that itreared its hatchlings.Maiasaura was the first dinosaur in space!

A fragment of bone and a piece of eggshellflew with American astronaut Loren Acton onan eight-day shuttle mission in 1985.

LAST MEALEdmontosaurus (left) was a close relative of

Maiasaura. Scientistshave discovered howthis hadrosaur livedby studyingits fossilized skinand the food insideits stomach when itdied.

Maiasaura may have migrated in order to look forfood. As they marched across the plains,they kept their young in the centerof the herd so that they wouldbe safe from predators.

my-uh-SAWR-uh

27

Late Cretaceous North America, 74 mi llion years ago

Fossil remains ofMaiasaura werediscovered along

with those of nests, eggshells,and hatchlings. Thehatchlings’ cute appearance(large head and eyes) madethe mother Maiasaura feelmaternal towards her brood!

To lay its eggs,Maiasaura dug ahole in soil withits feet. It laid30-40 largeeggs in a spiral.Then it built a

wall aroundthem with its snout. Tokeep the eggs safeand warm, itcovered them with

leaves. Themother guarded

the nest untilthe eggshatched.Maiasaura feeds her babies.

AMONG THE PLANT-EATING DINOSAURS were the largest, longest and tallest

animals that ever walked the Earth. With their elongated necks and tails, giant

sauropods like Diplodocus and Brachiosaurus are some of the best known. But the

plant-eaters also included Stegosaurus, the dinosaur with diamond-shaped plates

running down its back, tank-like Euoplocephalus, covered from head to toe with bony

plates, and triple-horned Triceratops, with its giant neck frill.

Meet them all here in this book.

DDiinnoossaauurriiaaPPLLAANNTT--EEAATTEERRSS

DDiinnoossaauurriiaa

PLANT-EATERS

(UK)Job: E2-23542 Title: Dinofiles - Plant Eaters

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First published in 2012 by Orpheus Books Ltd.,6 Church Green, Witney, Oxfordshire OX28 4AW, England

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Copyright © 2012 Orpheus Books Ltd.

Created and produced by Nicholas Harris, Sarah Hartley, Erica Williams, Katie Sexton and Ruth Symons

Orpheus Books Ltd.

Illustrated by Julius T. Csotonyi, Steve Kirk, Simon Mendez, Eric Robson, Peter Scott,John Sibbick and Studio Inklink

Illustration copyright © Julius T. Csotonyi 8TRIllustration copyright © John Sibbick 6BL, 13TL, 21CL and 29TR

Text by Olivia Brookes

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic,

mechanical, photocopying, recording or otherwise, without the prior writtenpermission of the copyright owner.

ISBN 978 1 7418 3775 9

A CIP record for this book is available from the British Library

Printed and bound in China


#150 Dtp: 89 Page: 3(UK)Job: E2-23542 Title: Dinofiles - Plant Eaters

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DDiinnoossaauurriiaa

PLANT-EATERS

4 5

Introduction 5

Plateosaurus 6

Diplodocus 8

Stegosaurus 10

Brachiosaurus 12

Iguanodon 14

Hypsilophodon 16

Euoplocephalus 18

Contents Introduction

Styracosaurus 20

Parasaurolophus 22

Lambeosaurus 24

Maiasaura 26

Pachycephalosaurus 28

Triceratops 30

Index 32



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THE FIRST DINOSAURS were meat-eaters. But other kinds soonevolved to take advantage of the plentiful vegetation. The firstplant-eaters were the prosauropods. Like the meat-eaters, they

also walked on two legs. But, as time went on, they became longer andbulkier, so they walked on all fours. The sauropods, which evolved in theJurassic, included giants such as Diplodocus, Apatosaurus, andBrachiosaurus. They were the largest animals ever to walk on land. Thesauropods were joined by other kinds of plant-eaters, including thestegosaurs, dinosaurs with plates and spines on their backs, andankylosaurs, dinosaurs with bony armor that covered their bodies.

With no ability to chew their food, sauropods relied on pebbles that theyhad swallowed to grind up the vegetation in their stomachs to help withdigestion. Still other kinds of plant-eaters, the ornithopods, had jawsthat could grind up food in their mouths. They became the dominantplant-eaters of the Cretaceous. The sauropods, meanwhile, died outeverywhere except in South America.

PLATEOSAURUS walked sometimes on onits hind legs, other times on all fours. It had short arms, but its long neck

made it easy to reach leaves on highbranches. Its strong jaws were fullof small, sharp, leaf-shapedteeth.

If attacked, Plateosaurusrose up on its back legs. Itcould fight back using thesharp claws on its thumbsand toes. Its heavy tail wasa useful weapon, too.

With eyeson both sides

of its small head,it could see allaround whenlooking for food orwatching forenemies.

p lat-ee-uh-SAWR-us

6

Riojasaurus (right)lived in the deserts ofSouth America. Like itscousin Plateosaurus, ithad clawed toes.

Riojasaurus

Mussaurus

BURIED DEEP BELOWPlateosaurus means “flat-lizard.” Itgets its name from the flat shape of the first Plateosaurusfossils found in 1834. Scientists think thatPlateosauruses were very common dinosaursbecause so many of their fossils have been foundin the dry regions of Europe where they lived. In 1997, Plateosaurus fossil bones were found

in rocks more than a mile below the surface ofthe North Sea. This is the deepest place dinosaurfossils have ever been discovered.

Massospondylus (above) was tooheavy to walk upright. It had along neck so it could still reachleaves on trees. Mussaurus(below) means “mouse lizard”because the first tiny fossils foundwere only hatchlings.

7

P lateosaurus Late Triassic Europe, 220-200 mil lion years ago

Plateosaurus was 30 ft (9 m)long and 8 ft (2.4 m) tall.



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Diplodocus hadpeg-shaped teeth atthe front of itsmouth. These wereperfect for strippingleaves off branches.

DIPLODOCUS had a large, stocky bodywith pillar-likelegs and spikes

that ran down itsback. Its front legswere shorter thanits back legs. Usingits long neck, it

could easily reach itsfavorite foods: leaves, ferns,and water plants. It had along, whip-like tail, good fordefense against predators.

Diplodocus was 90 ft (27 m) long Diplodocus’s long neck was useful forscaring enemies or showing off to females.

Diplodocuses werefully grown at just10 years old.

8

LIGHT, LONG, AND LOUD Diplodocus’s name means “double beam” becauseof the shape of the bones inside its tail. It is thelongest dinosaur known to scientists for which acomplete skeleton has been found. Diplodocusmight have used its long tail for protection. Itcould swing it at attackers or crack it like awhip to scare them. Even thoughit was very long and large,Diplodocus weighed

only as much asthree elephants.

TW INKLETOESBelieve it or not, Diplodocuswalked around on tiptoe! It hadwide feet with a round heel bonepadded by a ball of flesh the sizeof a basketball. One of its toeshad a large claw.

Both Diplodocus and itsrelative Barosaurus(below) had necks morethan 20 ft (6 m) long. Theymay have had not one buteight hearts linkedtogether. Each helped topump blood all the way up to the head.

Amargasaurus(above) one ofDiplodocus’srelatives, had longspines on its neck.

dih-PLOD-uh-kus

9

Diplodocus Late Jurassic North America, 150-147 mi llion years ago

Shunosaurus had aspiny club at the end

of its tail.



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ROOF LIZARDThe name Stegosaurus means “rooflizard.” This is because scientists once wronglythought that its plates laid flat along its back,overlapping like roof tiles, instead of standing up.The plates probably helped control Stegosaurus’sbody temperature. The blood vessels inside eachplate would take in heat when the dinosaur neededto warm up, or give off heat when it needed to cooloff. Males might have also shown off the size orcolor of their plates to attract females duringmating.

WALNUT BRAINStegosaurus’s brain was only thesize of a walnut. It had tinyteeth and couldnot chew its food.Instead, it had toswallowstones thatwould grindup foodinside itsstomach.

Stegosaurus steh-guh-SAWR-us

Though it was a gentle plant-eater,Stegosaurus could put up a fight when dangerappeared. Turning its back on the enemy, it would swing its spiked tail into its head.

STEGOSAURUS had a bulkybody with a high, archedback and stocky limbs. It

walked with its small head lowto the ground and its spikedtail held high. It is probablybest known for the double rowof broad plates on its back.Stegosaurus used its greatsense of smell to findits favorite foods:mosses, ferns,and low-growing conifers.

Stegosaurus was 30 ft(9 m) long and 13 ft(4 m) tall.

Stegosaurus’splates were goodfor regulating itsbody temperature,attracting a mate,and scaringenemies.

An ancestor of Stegosaurus,Scutellosaurus (above) hadhundreds of bony scales allover its body. It was one of thefirst dinosaurs to have armor.

1110

Late Jurassic North America, 155-145 mi llion years ago



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Brachiosauruswas 82 ft (25 m)long and 43 ft(13 m) tall.

BRACHIOSAURUS was ahuge, four-legged sauropodwith a thick, fairly short tail.

Like a giraffe today, it had a verylong neck and its front legs werelonger than its back legs. Therewas a high crest on its head, largenostrils above its eyes, and manychisel-like teeth in its mouth.Brachiosaurus roamed the forestsof North America, eating cycad orginkgo leaves and pine needles.

Brachiosauruscould probablystand up on itshind legs to reachthe very tops of treeswhile eating. The bonesin its long neck were

hollow and not heavyto lift.

A fully-grown Brachiosauruswas so big that it was safefrom even the largestpredators, such as Allosaurus.The little ones still had towatch out, though!

12

A Brachiosaurusand a Ceratosaurusconfront oneanother.

WHO WAS BIGGEST?Brachiosaurus is the tallest andheaviest dinosaur known from acomplete skeleton. But scientistshave found enough bones fromArgentinosaurus, a large dinosaurthat lived in mid-CretaceousArgentina, to guess that thisdinosaur was most likely heavier.It probably weighed about 73 tons.

Supersaurus

Diplodocus

Brachiosaurus

bray-kee-uh-SAWR-us

13

Brachiosaurus

Argentinosaurus

ARM LIZARDBrachiosaurus means “arm lizard” because its frontlimbs were longer than its back limbs. This wasunusual for a dinosaur. Because of the way it stood,Brachiosaurus could have looked through the fourth-floor window of a building. The skeleton of a closerelative, Giraffatitan, in the Humboldt Museum ofBerlin, Germany, is the largest mounted skeleton inthe world. Brachiosaurus would have weighedbetween 30 and 50 tons.

Late Jurassic North America, 154 mi llion years ago



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IGUANODON was a large ornithopod. It had flexible arms, powerful hindlegs, and a strong, flat tail. It could

run very fast on two legs to escape frompredators. To help it walk or run throughsquishy, wet swamplands its toes couldbe splayed wide. Iguanodon used itssharp beak and teeth to tear ferns andcycads. Its thumbs, shaped like spikes,

made great defensiveweapons.

Fossil tracks reveal thatwhile Iguanodon sometimeswalked on all fours, itusually walked on two feet.As it walked, it leanedforward, using its flat, stifftail to help it balance.

Iguanodon was 30 ft (9 m)long and 10 ft (3 m) tall.

Iguanodon’s thumbspike was as much as6 in (15 cm) long. Itcould be also used torip open tough fruit orto tear down leaves.

14

LETHAL WEAPONIf a large, hungrytheropod attacked,and there wasnowhere to run,Iguanodoncould use itslong thumbspike to defenditself by stabbing itsenemy’s body. Thespike was strongenough to pierceeven thetoughest skin.

Iguanodon ate by holdingleaves or twigs in its sharpbeak, pulling them apart usingits little finger (below). Then itground them up with its cheekteeth. When these teeth woreout, new ones would grow in.

EARLY DISCOVERY Iguanodon was the second dinosaur ever to bediscovered, after Megalosaurus. Its fossils werefirst found in 1822. Its name means “iguana tooth”because its teeth are shaped like an iguana’s today.Other Iguanodon fossils have given strong cluesthat they lived in herds. When Iguanodon’s bones were first pieced

together in the 19th century, scientists thought itwas a sturdy, four-legged, bear-like animal with aspike on its nose. Later, it was thought the bonesshould be arranged to make it stand up like akangaroo. Nowadays, scientists agree thatIguanodon stood with its backbone horizontal.

ih-GWAH-nuh-don

15

Iguanodon Ear ly Cretaceous swamp lands, 130-120 million years ago



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“LITTLE LIZARD”Xiaosaurus (left) lived in Chinaduring the mid-Jurassic period. Itwas just 5 ft (1.5 m) long but hadsimilar features to Hypsilophodon:large eyes, a long, stiff tail, and itand ran on two long, slim legs.

Hypsilophodon was8 ft (2.4 m) longand 3 ft (1 m) tall.

Hypsilophodon

AMBUSH VICTIMTenontosaurus (above) was oncebelieved to be a very large memberof the Hypsilophodon family. Nowscientists think it is a more distantrelative. Its fossil remains werediscovered along with fossils ofseveral Deinonychus, which areknown to have hunted in packs.Poor Tenontosaurus was mostlikely the victim of an ambush bythese fierce pack-hunters.

LIVED AND DIED TOGETHER Hypsilophodon means “high ridgetooth.” It is named for its high-crowned, grooved cheek teeth. The remains of 24 Hypsilophodon wereonce found in the same place. This probablymeans that an entire herd died togetherafter becoming stuck inquicksand.

Camptosaurus(above) was a 20-ft(6 m) longornithopod. It wasan ancestor of theHypsilophodonfamily.

17

Ear ly Cretaceous Europe and North America, 120 mi llion years ago

Under threat fromits enemies,Hypsilophodon’s only choice was torun, and run fast.

Hypsilophodonsheared off leaves or

plants with its beakand stuffed them into its

cheek pouches. When old teethwore out, new ones grew in.

HYPSILOPHODON was like amodern mammal: a gazelle.It could run very fast on its

two long, slender legs. It had verylarge eyes, good for keeping a lookoutfor predators. Its two short arms eachhad five clawed fingers. It also had along, stiff tail that probably helped itbalance as it sprinted away fromtrouble at high speed.

KEEP ING WATCHHypsilophodon gathered in herds and spent theirdays nibbling low-growing plants on open plains.While most ate, some kept watch for danger.

16

hip-suh-LOF-uh-don



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Euoplocephalus was 20 ft (6 m)long and 7 ft (2m) tall.

Ankylosaurus(left) was an

armored dinosaurknown for itsclubbed tail and thesmooth, roundedknobs of bonecovering its back.

18

Ankylosaurs like Euoplocephalus,Ankylosaurus, Saichania (above),and Talarurus (below right) all had adefensive weapon: a large ball ofbone at the ends of their tails. Theyused it to swing at their enemies,such as Tarbosaurus (below left).

19

Euoplocephalus

Unlike Ankylosaurus,Euoplocephalus (left)had sharp spikesaround its head andshoulders. Both hadclubbed tails.

EUOPLOCEPHALUS was anarmored dinosaur. It had astocky, low-slung body, stout

legs, and clawed feet. Plates ofspiked, bony armor were found inthe skin on its neck, back, tail, andeven in its eyelids! It had largespines on its shoulders and a heavyclub at the end of its tail.

CLUBS AND ARMOREuopleocephalus means “well-armored head.” It got this namebecause of the bony spikes on its head.Even though it was nearly fully armored, itwas still vulnerable to attack from predators. So it most likely roamed in herds for safetyin numbers.

BIG TAIL, BIG NOSEThe name Talarurus means “basket tail,” sonamed for the shape of its tail club.Talarurus had large nostrils that met at thefront of its face to form one large opening.This probably helped it keep cool in thedeserts where it lived.

Late Cretaceous North America, 85-65 mi llion years agoyoo-op-luh-SEF-uh-lus



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Styracosaurus was 18 ft (5 m)long and 6 ft (1.8 m) tall.

STYRACOSAURUS had a longnose horn on its toothlessbeak and small horns on each

cheek. Its stocky body was like arhinoceros’s. Six long spikes andsome smaller knobs of bone stuckout from the edge of its neck frill.This frill helped keep the dinosaur’sbody temperature low. It probablyalso looked quite scary to itsenemies. The colors on the frill’sskin may have helped attract a mate.

All ceratopsians likeStyracosaurus had a similar body shape: massive headwith horn or horns, toothless beaks, neck frills andsturdy, pillar-like legs.

Styracosaurus’sfrill was not solidbone but had wideopenings covered in skin. Styracosaurus

PachyrhinosaurusAnchiceratops

Centrosaurus’s skeleton showstypical ceratopsian features:a gapped frill, a stocky body,and hoofed feet.

ON GUARD Protoceratops was a 7ft- (2 m) longceratopsian fromMongolia. Its teethwere perfect for slicingup semi-desert plants.It laid its sausage-shaped eggs in a nest,up to 18 at a time. Theeggs were about 8inches (20 cm) long.Protoceratops was veryprotective of its eggs.

CALL ME “SPIKE” The name Styracosaurus means “spikedlizard.” It was named for the spikes onits frill. The longest was 20 inches (51cm) long, about the length of an adulthuman’s arm. The frill may havechanged color during courtship.

THE LAST DINOSAURS Ceratopsians were one of the lastgroups of dinosaurs to evolve beforeall dinosaurs became extinct atthe end of the Cretaceousperiod. They had chopping

teeth, good forchewing thetoughest plants.Like elephants

and rhinos today,they may have been able togallop away from danger.

Scientists think they also livedtogether in herds for safety.

Psittacosaurus, or“parrot dinosaur,”was an earlyAsian ceratopsian.It was named forits bony, toothlessbeak.

sty-rak-uh-SAWR-us

21

Styracosaurus Late Cretaceous North America, 77-75 mil lion years ago

20



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PARASAUROLOPHUSwas a duck-billed dinosaur

(hadrosaur). It had a long face, a flatsnout, and a toothlessbeak. It walked on itstwo strong hind legs.Parasaurolophus’smost distinctive feature was its long,bony, hollow crest. Its skull alone was 6 ft(1.8 m) long, the height of an adult human!

A CREST IS GOOD FOR . ..Getting attention, mainly. It hadhollow tubes inside linked to thenose and could make deepbellowing sounds. These weregood for impressing mates,warning off rivals, or sounding analarm when danger appeared.Thecrest may also have helped thedinosaur keep a cool head byletting off heat from the brain.

Parasaurolophus fedon conifer needles andmagnolia leaves.

Parasaurolophus was 30 ft (9 m)long and 10 ft (3 m) tall.

22

Likeother

duckbills,Parasauro-

lophus had abony beak withstrong teeth inits cheeks forchewing leaves.It lived in herdsand migrated tohigher ground to build its nestand lay eggs.

This cross-section (above)shows Parasaurolophus’scheek teeth, large eyesockets, and nasal tubes

inside its longcurved crest.

YOU REM IND ME OF SOMEONE . ..Parasaurolophus means “near hollow lizard.”When scientists discovered it, they thought itlooked like another known dinosaur,Saurolophus, or “hollow lizard,” so they gave it“nearly” the same name. The crests of male Parasaurolophus may

have been longer than those of females with abrightly colored frill between the crest and theback of the neck. This could have helped themales make an impressive display whencourting females, just as many malebirds do today.

23

par-uh-sawr-uh-LOF-usParasaurolophus Late Cretaceous North America, 76-75 million years ago



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LAMBEOSAURUS was a typeof duck-billed dinosaur(hadrosaur). It had a flat,

tootless beak and a U-shapedneck. It walked through swampywoodlands on its long hind legs,feeding on leaves. Its short frontlegs had fleshy padded hooves. Itstail was wide and stiff. Differentspecies of Lambeosaurus haddifferent crest shapes: some werehatchet-shaped, while others werehigh and round.

Lambeosaurusmagnicristatus (above) had ahollow crest shaped like a high roundeddome. The crest may have amplified itsbellowing warning calls.

24

SNORKELS .. .Lambeosauruswas named forthe Canadiangeologist, LawrenceLamb, who was the firstperson to study it. It was once thoughtthat crested hadrosaurs like Lambeosauruswere aquatic animals that used their crests like snorkels or oxygen tanks to breathe underwater.

. .. AND HELMETSThe name Corythosaurus means “helmet lizard,” sonamed for the shape of its crest. Like Lambeosaurus,its crest contained nasal tubes that may have allowedit to make loud, deep warning or mating calls.

Hadrosaurs hadhundreds of teeth. Whenold, worn teeth fell out,new ones grew in.Hadrosaurs could chewup tough plants very welland had long twistedintestines (above), whichhelped digestion.

lam-bee-uh-SAWR-us

25

Lambeosaurus

Lambeosauruslambei

Lambeosaurus lambei’s crest was hatchet-shaped. Corythosaurus’s was curved.

Late Cretaceous North America, 76-75 million years ago

Baby hadrosaurshatch out oftheir eggs.They are likeminiatureadults, ableto walkimmediately.

Lambeosaurus was 30 ft (9m)long and 10 ft (3 m) tall.



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MAIASAURA was a duck-billeddinosaur (hadrosaur). It had along snout, a toothless

beak, and crests above its eyes.Inside its cheeks were many self-sharpening teeth, perfect forgrinding up plants, berries,leaves, and seeds. Its scaly skinwas covered with warts. Likeother hadrosaurs, it walkedsometimes on two legs, other timeson all fours. Its back legs were longerand stronger than the front ones. Its toeshad fleshy pads on their undersides.

Maiasaura was 30 ft (9 m)long and 10 ft (3 m) tall.

26

Maiasaura

DINOSAUR ASTRONAUT Maiasaura means “good mother lizard.” Itwas so named because of the evidence that itreared its hatchlings. Maiasaura was the first dinosaur in space!

A fragment of bone and a piece of eggshellflew with American astronaut Loren Acton onan eight-day shuttle mission in 1985.

LAST MEAL Edmontosaurus (left) was a close relative of

Maiasaura. Scientistshave discovered howthis hadrosaur livedby studying its fossilized skinand the food insideits stomach when itdied.

Maiasaura may have migrated in order to look forfood. As they marched across the plains,they kept their young in the centerof the herd so that they wouldbe safe from predators.

my-uh-SAWR-uh

27

Late Cretaceous North America, 74 mi llion years ago

Fossil remains ofMaiasaura werediscovered along

with those of nests, eggshells,and hatchlings. Thehatchlings’ cute appearance(large head and eyes) madethe mother Maiasaura feelmaternal towards her brood!

To lay its eggs,Maiasaura dug ahole in soil withits feet. It laid30-40 largeeggs in a spiral.Then it built a

wall aroundthem with its snout. Tokeep the eggs safeand warm, itcovered them with

leaves. Themother guarded

the nest untilthe eggshatched.Maiasaura feeds her babies.



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PACHYCEPHALO-SAURUS walked on itshind legs. Its thick,

stiff tail helped its balance. Ithad short, stubby arms withclawed fingers. Its smooth,domed skull had bony knobsjust above its stocky neck.There were also short, bonyspikes on its snout. Itchewed leaves and fruit withits tiny cheek teeth.

Pachycephalosaurus was15 ft (5 m) long and 7 ft(2 m) tall.

Just as rams and billy goats use their horns forfighting today, the thick, domed skulls ofPachycephalosaurus and its relatives may havebeen used for contests between rival malesduring the breeding season.

28

pak-ee-sef-uh-luh-SAWR-us

29

Pachycephalosaurus Late Cretaceous North America, 67-65 mi llion years ago

Stegoceras—no, notStegosaurus—was a close relativeof Pachycephalosaurus, only itwas about half the size of itscousin. As Stegoceras (above)grew older, the dome on its headgrew over the bony rim around

the sides and back of its head,just like a top hat.

THICK BUT SENSITIVE Pachycephalosaurus means“thick-headed lizard.” It wasnamed for its domed skull.Scientists think it probably had a verygood sense of sight and smell. These helped itspot predators in time to make its escape. It ranon two legs, leaning forward with its head andheavy tail held level.

YOUR NAME IS — WHAT?!Fossil remains of Stygimoloch (below) were firstfound among the Hell Creek rock formations inMontana. Its name means “horned devil from theriver of death.” It was named for where it was found,and for the scary 6-inch (15 cm) spikes onits head.

Triceratops was 30 ft (9 m)long and 8 ft (2.4 m) tall.

P IECE BY PIECE The name Triceratops means “three-hornedface.” What we know about Triceratops hasbeen pieced together from hundreds offossil pieces. A complete skeleton hasnever been found.

HEAVY FRILL Only Triceratops had a frill that was madeof solid bone. Its relatives had gaps intheir frills covered with skin, which madethem lighter. Triceratops’s neck frill wasover 6 feet (1.8 m) long. Together with itssnout, its colossal head was more thanone-third the length of its whole body.

try-SER-uh-tops

30 31

Triceratops

Threatened by attack from a Tyrannosaurus,Triceratops stood its ground andtried to look as mean and fiercepossible. It lowered its headto show off its neck frilland horns.

TRICERATOPS had amassive head with a longsnout. Its neck frill was

made of solid bone. It had twolong horns over its eyes and oneshorter one just behind itsparrot-like beak. Inside its mouthwere hundreds of sharp teethused for grinding down toughplants and leaves. The skincovering its huge body wastough. Triceratops was so bigthat most predators would haveshied away from attacking it.

Late Cretaceous North America, 65 million years ago

Two Triceratopstake a drink.



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32

IndexPage numbers in bold refer toillustrations

AAbydosaurus 12Acrocanthosaurus 14, 15Albertaceratops 20Allosaurus 10Amargasaurus 8, 9Amphicoelias 8Anchiceratops 20, 30ankylosaurs 5, 18, 19Ankylosaurus 18, 19Apatosaurus 8Argentinosaurus 13Arrhinoceratops 30Astrodon 12Avaceratops 20

BCBarosaurus 8, 9Brachiosaurus 12-13Brachylophosaurus 26Camptosaurus 14, 16, 17Cedarosaurus 12Centrosaurus 20, 21, 30ceratopsians 20-21Ceratosaurus 12Charonosaurus 22, 24Chasmosaurus 30Corythosaurus 22, 24, 25crest 22, 23, 24, 25

DEDeinonychus 17digestion 5, 11Diplodocus 8-9, 13Dryosaurus 14, 16duckbills see hadrosaursEdmontosaurus 26, 27eggs 21, 23, 25, 26-27Einiosaurus 20Euoplocephalus 18-19

GHIgastroliths 11Giraffatitan 12hadrosaurs (duckbills) 22-27hatchlings 25, 26-27Homalocephale 28Huayangosaurus 10Hypsilophodon 16-17Iguanodon 14-15, 16iguanodonts 16

KLMKentrosaurus 10Lambeosaurus 22, 24-25Lexovisaurus 10Lufengosaurus 6Lusotitan 12Maiasaura 26-27Massospondylus 6, 7Mussaurus 6, 7Muttaburrasaurus 14

NOneck frill 20, 21, 30, 31nest 23, 25, 26-27Olorotitan 22, 24ornithopods 5, 14, 16-17Ornithosuchus 6Ouranosaurus 14

PRPachycephalosaurus 28-29Pachyrhinosaurus 20Parasaurolophus 22-23, 24Pentaceratops 30Pinacosaurus 18Plateosaurus 6-7Prenocephale 28prosauropods 5, 6-7Protoceratops 21Psittacosaurus 21Riojasaurus 6, 7

SSaichania 18, 19Saurolophus 23, 26sauropods 5, 8-9, 12-13, 25Sauroposeidon 12Scutellosaurus 11scutes 11Sellosaurus 6Shantungosaurus 26Shunosaurus 9Sonorasaurus 12Stegoceras 28stegosaurs 5, 10Stegosaurus 10-11Stygimoloch 28, 29Styracosaurus 20-21, 30Supersaurus 8, 13

Ttail club 9, 18, 19Talarurus 18, 19Tarbosaurus 19Tenontosaurus 16, 17thumb spike 14, 15thumb-claws 6, 7titanosaurs 13Torosaurus 30Triceratops 30-31Tsintaosaurus 22, 24Tuojiangosaurus 10Tyrannosaurus rex 30

UWXYUnaysaurus 6Wuerhosaurus 10Xiaosaurus 16Yunnanosaurus 6


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