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My First Library of Knowledge
Dinosaursand other prehistoric life
Orpheus
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EARTH is 4600million years old. Life
on our planet probablybegan about 3800 millionyears ago.The first lifeforms were microscopicthings, neither animalsnor plants. It took another3600 million years beforea certain kind of reptileappeared. Some of thesereptiles were the largestand fiercest creatures theworld has ever seen.They were the dinosaurs.
CONTENTS INTRODUCTIONFirst published in 2005 by Orpheus Books Ltd.,
2 Church Green,Witney, Oxfordshire, OX28 4AW
Copyright © 2005 Orpheus Books Ltd.
Created and produced by Rachel Coombs,
Nicholas Harris, Sarah Harrison, Sarah Hartley,
Emma Helbrough, Orpheus Books Ltd.
Text Nicholas Harris
Consultant Professor Michael Benton, Department of
Geology, Bristol University
Illustrated by Inklink Firenze, Nicki Palin,
Gary Hincks, Peter Dennis
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
written permission of the copyright owner.
ISBN 1 901323 XX X
A CIP record for this book is available from the
British Library.
Printed and bound in Singapore
4 HOW THE EARTHBEGAN
6 THE FIRST LIVINGTHINGS
8 THE FIRST FISH
10 COAL SWAMPS
12 THE FIRST DINOSAURS
14 JURASSIC DINOSAURS
16 PLANT-EATINGDINOSAURS
18 FLESH-EATINGDINOSAURS
20 DUCKBILLEDDINOSAURS
22 CRETACEOUSDINOSAURS
24 THE END OF THEDINOSAURS
26 PREHISTORIC BIRDSAND MAMMALS
28 THE FIRST HUMANS
30 DINOSAUR FOSSILS
32 INDEX
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Soon afterthe Earth hadformed another smallplanet (1) collided with it andexploded (2).
Allforms oflife need waterto survive. Life mayhave arisen in the Earth’swarm, shallow seas.
1
2
3
4
5
6
4 5
LIKE all the planets,the Earth was formed
about 4600 million yearsago. In its early years, ithad no water or life, justbarren rock. Meteorites(large boulders), raineddown from space. Lifeprobably arose 3500million years ago.
HOW THE EARTH BEGANThe fragments collected in orbit
round the Earth, which wasby now a ball of
melted rock(3).
To begin with, the Earth was a barren planet. Butvolcanoes blasted out gases from beneath its surface.
One of these gases was water vapour. Cloudsformed (5) and, later, rain fell. It rained
for millions of years until basinsfilled to become the
oceans (6).
THE SOLAR SYSTEMThe planets were once billionsof small rocks whirling roundthe Sun.They “snowballed”into large, rocky globes.
The Earth’s surfacelater cooled andturned back to solidrock. The orbitingfragments cametogether to form the
Moon (4).
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6 7
THE CAMBRIAN SEASThe first animals with hard parts—shells or bony skeletons—firstappeared about 540 million yearsago.This was at the beginning of atime in Earth’s history thatscientists call the Cambrian Period.
These animals lived in warm,shallow seas.They includedshellfish, corals, starfish, molluscsand sponges. Some very strange-looking animals swum in theCambrian seas! One, Opabinia,had five mushroom-shaped eyes.
THE F IRST L IVING THINGS
THE FIRST livingthings appeared not
on land, but in the oceans.They were very tiny life-
forms called bacteria.Thefirst animals were soft-bodied sea creatures, suchas jellyfish and worms.
One of the creatures of the Cambrian seas, called Pikaia, appearedto be half-worm, half-fish. It may have been an ancestor of allbackboned animals, including reptiles, birds and mammals.
Anomalocaris
TrilobiteJellyfish
Pikaia
Opabinia
Sanctacaris
Leanchoilia
Wiwaxia
Hallucigenia
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FISH WITH JAWS
Over millions of years,fish with fins appeared.Fins allowed them to steermore easily and swimfaster. Some fish also hadjaws and teeth.Theycould now feed on othersea creatures.
THE F IRST F ISH
THE FIRST fish hadno fins or jaws.
They swam with theirmouths open suckingin things to eat.
TRILOBITESTrilobites first appeared in theCambrian seas.They became verycommon animals for the next 250million years.Their bodies weredivided into three lengthwisestrips, or lobes.They used their legsto carry food to their mouths.Some kinds could roll themselvesinto a ball for protection.
A trilobite used its legs towalk on the sea floor, or topaddle through the water.
The first fish hadbony armour-plating to defendthem from attack.
Water scorpions were fierceanimals. They scuttled aroundon the sea floor hunting fish.They caught them in their claws.
Dunkleosteuswas a nine-metre-long seamonster.Instead of teethit had hugeplates of bonein its jaws.These actedlike slicerblades.
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COAL SWAMPS
ABOUT 350 millionyears ago, some
parts of the world werecovered by hot, steamyjungle. Giant dragonfliesflitted among the trees.Huge centipedes and
amphibians lurked in theswampy undergrowth.Thecoal we have today wasformed from peat, a darksoil that is produced fromlayers of rotting plantmatter in these swamps.
AMPHIBIANSSome kinds of fish, calledlobefins, had fleshy fins,which they used to heavethemselves on to land.Eventually, they spentmost their lives on land,returning to the wateronly to lay eggs.They were thefirst amphibians.
Dendrerpeton(ancient amphibian)
Giant dragonfly
Giantcentipede
Hylonomus(ancient reptile)
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THE F IRST DINOSAURS
SOME amphibiansbecame able to laytheir eggs on land,avoiding the need toreturn to water. Sincethey could live in dry
lands, these animals, thefirst reptiles, spread allover the world. Somekinds of reptile could runabout on two legs.Theywere the first dinosaurs.
WHAT IS A DINOSAUR?Dinosaurs were reptiles that livedon land in the Triassic, Jurassic orCretaceous Periods (250-65 millionyears ago).They walked uprightlike mammals or birds, notsprawling like other reptiles.Neither marine reptiles nor flyingreptiles (pterosaurs) were dinosaurs.
Coelophysis
Technosaurus
Pterosaur
A modern reptile(above) has legs atthe side of its body.A dinosaur (right)had straight,upright legs.
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JURASSIC DINOSAURS
THE first dinosaurswere flesh-eaters.
But by the Jurassic Periodthere were also manyplant-eating kinds.Theseincluded the long-necked
sauropods and thestegosaurs, dinosaurs withplates running down theirbacks.The 12-metre-longAllosaurus preyed onthese plant-eaters.
THE FIRST BIRDSThe first birdsappeared in theJurassic Period.They were probably descended
from small flesh-eating dinosaurs.Some of thesedinosaurs areknown to havehad feathers.
Ornitholestes
Allosaurus
Allosaurus
Camarasaurus
Stegosaurus
Diplodocus(long-necked sauropod)
Archaeopteryx
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FIGHTING BACK!No plant-eating dinosaur couldafford to be off its guard.A flesh-eater might launch an attack atany time.An Iguanodon wasneither quite large enough to putan attacker off, nor quick enoughto run away. Instead, it had sharpspikes for thumbs. If any dinosaurdared to attack it, the Iguanodonwould rear up on its back legsand jab a spike into thepredator’s body.
PLANT-EATING DINOSAURS
BRACHIOSAURUSwas a giant plant-
eating sauropod.Taller thana four-storey building, itssheer size protected it fromattack.Tiny Hypsilophodonlived in herds. It sprinted forsafety whenever threatened.
Brachiosaurus
Brachiosaurus
Hypsilophodon
IguanodonIguanodon
Acrocanthosaurus
MARINE REPTILESReptiles were also masters ofthe oceans. Ichthyosaurs lookedlike dolphins, while plesiosaurs,with their small heads and longnecks, resembled dinosaurs.
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prey, they used their clawsto slash through the hide,
fatally woundingtheir victim.
DINOSAUR PREDATORSThe flesh-eating dinosaurs, knownas theropods, all moved about ontwo legs, to keep their front limbsfree for grasping their prey.Large theropods hunted alone,while some smaller ones workedtogether in packs.
FLESH-EATING DINOSAURS
SOME plant-eatingdinosaurs had acovering of bony armourto protect them fromattack. Sauropelta wascovered in studs and
spikes. But a gang ofDeinonychus knew howto overcome its defences.On each of their feet theyhad a massive, curvedclaw. Rushing at their
Deinonychus
Deinonychus
Sauropelta
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DUCKBILLED DINOSAURS
THESE dinosaurslived in the
Cretaceous Period.Their snouts were wideand flat, and lookedquite like duck’s bills.
They had hundreds ofhard-wearing teeth intheir jaws.This allowedthem to feed on all kindsof plants, including leaves,ferns and pine needles.
HOLLOW CRESTSMany duckbills had crests on topof their heads. Parasaurolophushad a very long, backward-pointing one.These crests werehollow with tubes inside, and wereconnected to the noseand throat.
They probably helped to make thedinosaur’s warning calls to othermembers of its herd much louder
and deeper.
Edmontosaurus
Parasaurolophus
Corythosaurus
Lambeosaurus
Pteranodon
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KING OF DINOSAURSOne of the largest flesh-eatingdinosaurs, 12-metre-longTyrannosaurus rex had massive,
powerful legs and teeth as sharp assteak knives. It would charge at itsprey, bringing it down with thehuge claws on its feet.
CRETACEOUS DINOSAURS
TWO of the best-known dinosaurs
lived at the end of theCretaceous Period.Theplant-eater,Triceratops,
had three horns on itshead and a large neck frill.Tyrannosaurus was one ofthe few predators powerfulenough to attack it.
The first mammals appeared inthe Age of Dinosaurs. They weretiny creatures, emerging usuallyonly at night to feed.
While dinosaurs ruled onland, pterosaurs such asPteranodon, flew in the skies.Sheets of skin between thefourth finger and body madeup their wings. They usedtheir beaks for seizing fish.
Triceratops
Triceratops
Pteranodon
Tyrannosaurus
Ancientmammal
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THE END OF THE DINOSAURS
ATTHE END of theCretaceous Period,
all the dinosaurs suddenlydied out. No one knowswhy this happened. Itwas not only dinosaursthat became extinct.Pterosaurs and many
kinds of sea creaturesalso disappeared forever.The world may havebecome a bleak, colddesert for a time, whereonly a few kinds ofanimals could survive.
WHY DID THE DINOSAURSBECOME EXTINCT?Many scientists think that a giantasteroid (a rocky object in space)that crashed to Earth at this timewas the culprit. Millions of tonnesof rock and dust would have beenthrown up high into the sky by theexplosion.This would have blottedout the sun and changed theweather for years.The Earth wouldhave become a frozen world.
Tyrannosaurus
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GIANT BIRDSWhenTyrannosaurusbecame extinct, there wereno giant predators—for awhile.Then, massive, flight-less birds, three metres tall,took their place.These fierce,fast-running beasts preyed onsmall horses, crushing themto death in their huge,pointed beaks.
THE STORY OFMAMMALS
While the dinosaurs werearound, mammals were tiny,shrew-like creatures.Whendinosaurs disappeared, manykinds of mammals evolved(changed over time).Theyincluded the ancestors ofhorses, elephants, cats, whales,bats, monkeys—and humans.
PREHISTORIC B IRDSAND MAMMALS
BIRDS and mammalssurvived when the
dinosaurs were wiped out.Prehistoric kinds were verydifferent to modern ones.
Diatryma, aflightless bird,lived 60 millionyears ago.
Chriacus(a prehistoricmammal)
Hyracotherium(a prehistoric horse)
Diatryma
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NEANDERTHALSNeanderthal humans evolvedabout 400,000 years ago.Theywere named after the valley inGermany where their bones werefirst discovered. Short and stocky,they had low foreheads, thickridges above their eyes and widenoses.They hunted and fished,cooked their food over fires, builtshelters and buried their dead.Theylived until about 30,000 years ago.
THE F IRST HUMANS
THE FIRST human-like creatures lived in
Africa, probably morethanfour millionyears ago.They were
descended from apes, but,unlike apes, they walked
upright ontwo legs. Laterhumans spreadto all parts ofthe world.
APE-MENEarly humans lived together insmall groups.They were stillape-like in appearance.About2.5 million years ago, thesehumans were able to makesimple stone tools.They usedthem to kill and skin animals.
Neanderthalhunters
Woollymammothcaught in trap
The first tools usedby humans werestone blades. Theywere made bystriking one stoneagainst another tomake a sharp edge.
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HOW FOSSILS FORM
Fossils form when a deadanimal is buried in sediments(sand or mud). Its soft parts rotaway. Chemicals in water fillthe tiny spaces inside the hardparts such as bone, teeth orshell. Over millions of years, the
sediments turns to stone,leaving the shape of
the animal asa fossil.
EXCAVATION SITEThe fossil hunters use picks andshovels to clear the rock away.They use blades or toothbrushesto do careful work.After recordingthe exact size and position of theirfinds, they take away the bonesprotected by foam or plaster..
DINOSAUR FOSSILS
DINOSAURS mayhave died out 65
million years ago, but thesearch goes on today fortheir fossils (their remains,turned to stone). Scientistscan find out all aboutdinosaurs—what theyate, how fast theyran, how brainythey were—from studyingtheir fossils.
They look for fossils inrocks that were formedduring the Age ofDinosaurs. Besides bones,they may also find foot-prints or eggs.
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INDEXAAcrocanthosaurus16
Allosaurus 14-15amphibians 10-11,
12first 11
animals,backboned 7first 6-7sea 7, 24
Anomalocaris 6apes 28Archaeopteryx 15asteroid 25
Bbacteria 6birds,first 15prehistoric 26-27
Brachiosaurus 16-17
CCamarasaurus 15Cambrian Period 7,8
Cambrian seacreatures 6-7
centipedes, giant10-11
Chriacus 27climate change 25coal swamps 10-11Coelophysis 13Corythosaurus 21Cretaceous Period13, 20-21, 22-23,24
DDeinonychus 18-19Dendrerpeton 10Diatryma 26-27dinosaur, definitionof a 13
dinosaurs 12-25, 30Age of 22, 30armoured 18attacks by 16-17,18-19, 22-23
calls of 21duckbilled 20-21extinction of24-25, 26-27, 30
feathered 15first 12-13, 14flesh-eating 14-15,18-19, 23
plant-eating14-15, 16-17,18, 22
Diplodocus 15dragonflies, giant10-11
Dunkleosteus 9
EFEarth 4-5, 7formation of 4-5
Edmontosaurus 20fish 8-9, 11, 23first 8fossils 30-31
HHallucigenia 6horses, prehistoric26-27
humans, first 28-29Hylonomus 11Hypsilophodon16-17
Hyracotherium 26
IKLichthyosaurs 17Iguanodon 16-17jellyfish 6Jurassic Period 13,14-15
Lambeosaurus 21Leanchoilia 7life, origin of 4-5lobefin fish 11
MNmammals,evolution of 27first 22prehistoric 26-27
mammoths 29meteorites 4Moon, formation of4
Neanderthalhumans 29
Ooceans 6formation of 5
Opabinia 7Ornitholestes 14
PParasaurolophus20-21
Pikaia 7
planets 4Plesiosaurs 17Pteranodon 21, 23pterosaurs 13, 21,23, 24
Rreptiles 13first 11, 12marine 13, 17
rocks 4, 30-31
SSanctacaris 7Sauropelta 18sauropods, long-necked 14-15, 16
Solar System 4space 4, 25stegosaurs 14Stegosaurus 15Sun 4
TTechnosaurus 13theropods 19Triassic Period 13Triceratops 22trilobites 7, 8Tyrannosaurus rex22-23, 24
Wvolcanoes 5water scorpions 8water vapour 5Wiwaxia 6worms 6
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