LIFE ON EARTH ON THE LAND THE DIAGRAM GROUP Life On Earth: On the Land Copyright © 2004 by The Diagram Group Written, edited, and produced by Diagram Visual Information Ltd Editorial director: Denis Kennedy Editors: Bender Richardson White, Gordon Lee Contributor: John Stidworthy Indexer: Martin Hargreaves Art director: Roger Kohn Senior designer: Lee Lawrence Designers: Anthony Atherton, Christian Owens Illustrators: Julian Baker, Pavel Kostal, Kathleen McDougall, Coral Mula, Graham Rosewarne Picture researcher: Neil McKenna All rights reserved No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval systems, without permission in writing from the publisher For information contact: Facts On File, Inc 132 West 31st Street New York NY 10001 For Library of Congress Cataloging-in-Publication Data, please contact Facts On File, Inc ISBN 0-8160-5047-3 Facts On File books are available at special discounts when purchased in bulk quantities for businesses, associations, institutions, or sales promotions Please call our Special Sales Department in New York at 212/967-8800 or 800/322-8755 You can find Facts On File on the World Wide Web at: http://www.factsonfile.com Printed in the United States of America EB Diagram 10 This book is printed on acid-free paper Contents Introduction THE LAND Land Climatic zones 10 Life on land 12 Mass extinctions FOSSILS 14 Becoming a fossil 16 Dating fossils 18 Fossil fuels ANIMALS WITHOUT BACKBONES 20 Snails and worms 22 Spiders and scorpions 24 Millipedes and centipedes 26 Invertebrates AMPHIBIANS AND REPTILES 28 Frogs and toads 30 Salamanders 32 Early reptiles 34 Rise of the dinosaurs 36 Dinosaurs in variety 38 Tortoises and tuataras 40 Lizards 42 Snakes MAMMALS 44 First mammals 46 Egg-laying mammals 48 Ancient marsupials 50 Carnivorous marsupials 52 Plant-eating marsupials 54 Primitive placentals 56 Insectivores 58 60 62 64 66 68 70 72 74 76 78 80 82 84 Edentates Primates Rabbits and rodents Squirrels Mice and guinea pigs Carnivores Ancient carnivores Modern carnivores Primitive hoofed mammals South American hoofed mammals Odd-toed hoofed mammals Even-toed hoofed mammals Ruminants Elephants BIRDS 86 Running birds BIOMES 88 Tropical rainforest 90 Temperate woodland 92 Boreal forest 94 Tropical grassland 96 Temperate grassland 98 Desert 100 Mountains 102 The polar regions 104 Timeline 106 Glossary 109 Websites to visit 111 Index Introduction T his book is a concise, illustrated guide to living things that evolved on, and now inhabit, the land Texts, explanatory diagrams, illustrations, captions, and feature boxes combine to help readers grasp important information A glossary clarifies the more difficult scientific terms for younger students, while a list of websites provides links to other relevant sources of additional information Chapter 1, The Land, looks at the living conditions that animals face on land, and briefly reviews the course of evolution among land animals It also covers the topic of mass extinctions throughout the Earth’s history Chapter 2, Fossils, tells how fossils are formed, how they are dated, and how some are important to us as fuels Chapter 3, Animals without Backbones, gives an outline of the main groups of invertebrates, both living and extinct, that have taken to life on land These include snails, worms, and various groups of arthropods—animals with jointed legs Chapter 4, Amphibians and Reptiles, looks at the evolution of these two groups of vertebrates, with examples of their modern species Chapter 5, Mammals, is the longest section, examining the ancient history of mammals, and then taking a closer look at the various main groups, or orders, that make up this important group of land animals Chapter 6, Birds, describes those birds that have forsaken flying, to parallel the lifestyle of the running mammals Chapter 7, Biomes, looks at the various main habitats on Earth, and how living things are adapted to them, with examples of characteristic species On the Land is one of six titles in the Life On Earth series that looks at the evolution and diversity of our planet, its features, and living things, both past and present The series features all life-forms, from bacteria and algae to trees and mammals It also highlights the infinite variety of adaptations and strategies for survival among living things, and describes different habitats, how they evolved, and the © DIAGRAM communities of creatures that inhabit them Individual chapters discuss the characteristics of specific taxonomic groups of living things, or types of landscape, or planetary features Life On Earth has been written by natural history experts, and is generously illustrated with line drawings, labeled diagrams, and maps The series provides students with a solid, necessary foundation for their future studies in science Land Biomes These are areas of similar climatic conditions where comparable types of vegetation occur T HE MAIN CONTINENTAL BLOCKS have not always been arranged as they are today Over millions of years, slow geological processes have gradually shifted the “plates” of the Earth’s crust that carry the continents At various times in the past they came together in different ways For example, Australia, Antarctica, and South America were once connected The geography of the past had great influence on the evolution of various animal and plant groups, and governed their ability to spread Continental movements led to collisions that sometimes crumpled the edges of the main continental blocks slowly over millions of years The Himalayas are the result of India moving up from the south, and colliding with the main block of Asia The Andes have been thrust up where the Pacific Ocean plate meets South America The Himalayas and Andes are “young” mountains, and contain many of the world’s Land makes up about 30 percent of the Earth’s surface It is a vast area of 57.5 million square miles (149 million sq km) Two-thirds of the land area in the present world is in the Northern Hemisphere, with Australia, most of South America, part of Africa, and some outlying islands of Asia in the Southern Hemisphere Biomes ON THE LAND THE LAND highest peaks Older mountains, such as those in Scotland, have been worn down over hundreds of millions of years, and are relatively low The average height of the continents above sea level is about 2,756 feet (840 m), but there is a huge variation in height from the tallest mountain, Everest, at 29, 140 feet (8,882 m), to some parts of the land, such as the shore of the Dead Sea, that are as much as 1,299 feet (396 m) below sea level The land contains some areas, such as parts of Australia, or Eastern Europe, with flat plains stretching far and wide The enormous variation in landforms entails a similar variation in the adaptations of the animals that live there This is one reason for the existence of a huge range of animals in the modern world, and throughout the many millions of years that animals have lived on the land Tropical forest biome Found near the equator where conditions are warm and very wet ! IT’S A FACT The world’s continents, in order of size (1,000 millions), are as follows: Continents a Asia b Africa c North America d South America e Antarctica f Europe g Australia Sq mi 17.5 12 9.5 5.2 3.0 The world’s continents a b c d Desert biome Very dry, often hot, and with few plants Covers one fifth of the land Coniferous forest biome Forests with long winters and short summers Grassland biome Warm or temperate, but with not enough water f0r trees to grow Temperate forest biome Temperate, with enough water for tree growth Many trees drop their leaves in winter Tundra biome Frozen for much of the year with dwarf plants e f g Sq km 44 31 24 18 13 10 8 Climatic zones The world has a series of marked climatic zones Equatorial regions are warmed by sunlight throughout the year Temperatures are lower toward the Poles, where sunlight has to penetrate a thicker layer of atmosphere before reaching the surface B ECAUSE OF THE TILT of the rotating Earth, the North and South Poles are plunged into darkness in the middle of their winters The circulation of winds and ocean currents also affects climate, but the basic pattern is clear The tropics are very warm throughout the year At higher latitudes there is a temperate zone, with warm summers but cooler winters At the highest latitudes, near the Poles, there is a cold climate all year with, at most, a brief summer during which some ice may melt It is not surprising that, in general, life is more abundant and varied in the warm parts of the world, January Temperature belts in January and July Seasonal temperatures differ more the greater the distance from the equator (Temperatures are given below in both Fahrenheit and Celsius.) July Below -30 F -34 c 0 -34 c to c 0 -1 c to 10 c -30 F to 30 F 30 F to 50 F 0 50 F to 70 F 0 70 F to 90 F Over 90 F 0 0 0 10 c to 21 c 0 21 c to 32 c Over 32 c ON THE LAND THE LAND Age of dinosaurs At his time the world enjoyed a warm climate as long as there is water available The icy wastes of Antarctica are least likely to support life, but there are no places on the Earth entirely devoid of living things In mountains, temperature drops with height, so different climatic zones are found at different heights On the highest mountains the summits tend to have an Arctic feel The world can be divided into a number of “biomes,” defined by climate and rainfall Each has its own typical vegetation and animal life, although the species may not be the same on different continents But it was not always warm in the past There is evidence of great ice ages 445 million years ago, and again about 300 million years ago It is only recently, geologically speaking, that the world emerged from an ice age Ice cover disappeared from North America about 11,000 years ago Some people believe that we are now in a short, warm period within this ice age ! IT’S A FACT It cannot be assumed that today’s climates are typical of the past For much of the Cretaceous period (144 to 65 million years ago) the Earth had a warm climate Even near the Poles it was warm, so that temperatures were far more even across the world than now This was the heyday of the dinosaurs and pterosaurs, and they lived from the equator to the Antarctic, even though the polar winters must have been dark © DIAGRAM Cretaceous period At the end of this period continents had not reached their present positions ON THE LAND BIOMES Dry eroding hill Rocky landscape with few plants Shifting sand dunes Desert (above and below) In a desert, rocks and hills are continually eroded In some places sand forms and wind produces huge, shifting sand dunes ! IT’S A FACT Camels cannot avoid the Sun, but achieve some insulation from its rays from their fur, and the fatty humps on their backs When short of water, a camel may not sweat until its temperature is 140ºF (40ºC), a little above its normal level It allows its temperature to drop below normal in the cool night, so takes longer to warm up in the morning It can become much more dehydrated than a human before becoming distressed When really thirsty, camels can drink more than 60 pints (35 liters) of water Camels have nostrils which can be closed, long eyelashes, and fur in the ears to keep sand out They have pads on their toes to stop them sinking in soft sand Their adaptation for desert life is superb © DIAGRAM use of tiny amounts of dew forming at night Reptiles also lose water slowly through their dry scaly skins Even so, they have to hide in rock crevices, or under sand, to avoid the extreme heat which occurs during the middle of the day Small mammals usually hide from daytime heat and emerge in the cool of the night Some, like the kangaroo rat, survive without drinking at all They extract water from the dry seeds they eat, and only produce minute amounts of very concentrated urine 99 100 Mountains Mountains have their own climates and provide a unique habitat for a range of wildlife Climates on a single mountain may vary to a great extent Snow leopard This animal hunts high in the mountains of central Asia O N MOUNTAINS the temperature drops by about 34°F (1°C) with every 500 feet (150 m) of altitude ascended Near the summits of high mountains the air is noticeably thinner, which means less oxygen is available than at sea level The Sun’s radiation may be fierce, but the thin atmosphere does not trap the heat, and the ground may warm up more than the air Nights are cold, and winds often blow furiously around the mountaintops Even at the equator, a high mountain like Kilimanjaro may have a permanent snowcap In between the mountaintop and the plain below is a succession of zones The zones on a mountain mimic those you might pass through as you moved from equator to pole at sea level There may be broadleaved Yak This animal lives higher than any other ox, and has been turned into a valuable domestic animal in Tibet Mountains ! ON THE LAND BIOMES Himalayas These are the highest mountains on Earth Mt Everest is the tallest peak at 29,140 feet (8,882 m) IT’S A FACT High altitude mammals often have increased oxygen-carrying capacity in the blood The vicuña has nearly three times as many red blood cells per pint (0.6 l) of blood as humans © DIAGRAM forest at the base, with a band of conifers above These stop at the “treeline,” where the average monthly temperature is 50°F (10°C) Above this are alpine meadows, changing higher up into vegetation resembling that of Arctic tundra Above this may be permanent snow Few animals can live near the mountaintops, but there may be a few insects and mites in sheltered spots Most insects keep low to the ground when they fly to avoid being carried away by wind Even so, many insects, seeds, and pieces of plant, are blown up onto the snowfields, where a small number of birds, including choughs, eat them Most high mountain plants hug the ground They may have big roots below, but above ground they are flattened or cushionshaped Hairs may help them to trap heat Some large mammals survive well on mountains The yak lives high on the Himalayas, feeding on small plants, such as mosses and lichens in the winter Its fur is so thick that it can survive subzero temperatures Various types of wild sheep, goats, and antelope also live on these high mountains, but may move to lower slopes in winter Marmots stay high in the meadows and rocks, but hibernate during winter Some species of vole are adapted to the heights Pikas in Tibet are one of the highest permanent residents, with burrows at 18,045 feet (5,500 m) 101 102 The polar regions O N MOUNTAINS Lemmings above the ice These are one of the few some lichens grow One or two species rodents that are able to survive in the Arctic of insect and mite have been also been found But it is really only the fringes of Antarctica that are home to animals—mostly seabirds and mammals that are resting or breeding Seals haul themselves out of the ice to have their young Emperor penguins also incubates their eggs and chicks on the sea ice that is stuck to the land The Arctic, although extremely cold, is more hospitable to life The central part is ocean, frozen in the winter, but melting at the edges in high summer Within the Arctic Circle are the northernmost parts of the landmasses of North America and Eurasia In winter the ground is covered by snow and ice, and for months there is darkness In summer the days are long and the surface melts, but the subsoil is still frozen A vegetation of low tundra plants is then exposed Many are lichens or mosses, but there are also dwarf trees of birch and willow only a few inches (cm) high Some flowers also bloom in the very brief summer from June to September The continent of Antarctica lies in the southern polar region It is a barren land, permanently covered with ice, with high winds and temperatures that can drop to -126°F (-88°C) Conditions are too extreme for most life forms Polar bear This is the top predator in the Arctic, moving over the ice on its furry pads Arctic Circle South Pole North Pole Sea ice Antarctic Circle Ice sheet The Arctic Antarctica ON THE LAND BIOMES Many birds, including waders and geese, nest on the tundra in the light Arctic summer, then migrate once the young are reared Lemmings are permanent residents in the Arctic, staying under the snow in winter Ptarmigan, hares, voles, and ground squirrels are other plant-eaters that inhabit this area Arctic foxes, snowy owls, and hawks prey upon them The biggest plant-eaters on the tundra are musk oxen, which live in herds for protection Overall, few species live in the Arctic Food chains are short, and populations wax and wane over the years, never really reaching a stable equilibrium as they in more complex ecosystems Icebergs In the summer, these break off from the polar ice sheets and drift in the sea Animals are often carried with them ! IT’S A FACT Most small mammals find it difficult to keep warm at low temperatures However, the Arctic fox, with a head and body measuring feet (60 cm) long, and weighing only 11 pounds (5 kg), has such a dense undercoat that it can sleep on the surface of the snow at -58°F (-50°C) without coming to harm Its short ears and bushy tail—which it wraps around its face when sleeping—help the fox to conserve a large amount of heat © DIAGRAM Snowy owl (left) The male of this species is almost completely white, The female sits on a nest on the ground and, in contrast, is speckled with black 103 104 Timeline Million years ago Events 5,000–4,000 4,550 Formation of the Earth 4,000–2,000 3,600 Origins of life 2,000–400 1,400 First multicellular organisms 700 Ice age 560 First multicellular animals forming communities in the sea 545 Explosion of life in shallow seas; first shelled animals 455 First land plants 445 Ice age Centipede 417 First land animals 400–100 400 Centipedes in existence 375 First spiders; millipedes in existence 360 First “amphibians” 325 First reptiles 300 Ice age; most land forms a single landmass—Pangaea Early “amphibian” 250 Extinction of pelycosaurs 230 First dinosaurs 210 First mammals 205 Beginning of the age of dinosaurs 200 First frogs Pelycosaur 130 Early snakes 100–now 65 Impact of huge meteorite in Gulf of Mexico; extinction of dinosaurs 55 Early primates 50 First shrews 25 Saber-toothed cats come to prominence Early primate First mice Extinction of many South American mammal families Ice age Humans evolve Shrew ON THE LAND TIMELINE 105 Fossils help scientists determine when different kinds of plants and animals first appeared Era Millions of years ago Proterozoic Eon 2,500–543 Proterozoic periods bacteria, simple animals, and plants exist Paleozoic 543–490 Cambrian sea animals without a backbone flourish 490–443 Ordovician early fish appear 443–417 Silurian land plants and land arthropods appear 417–354 Devonian insects and amphibians appear 354–290 Carboniferous reptiles and flying insects live in forests 290–248 Permian reptiles dominate 248–206 Triassic dinosaurs dominate, mammals appear 206–144 Jurassic birds appear and pterosaurs flourish 144–65 Cretaceous flowering plants appear 65–1.8 Tertiary dinosaurs die out, mammals spread 1.8–present Quaternary humans dominate Cenozoic Main events © DIAGRAM Mesozoic Period 106 Glossary Amber Amphibian Caecilian Coprolite abdomen The posterior part of the body that contains the intestines in a backboned animal: the rear of three body sections in insects and crustaceans alpine Living in mountains amber The fossilized resin of pine trees amphibian Member of group of animals which may live on land as adults, but lay eggs in water that develop through a larval (tadpole) stage antennae The feelers on the head of jointed-legged animals aquatic Living in water arthropod An animal with an exoskeleton and jointed limbs and body artiodactyl An animal in the group of hoofed mammals with an even numbers of toes atmosphere The layer of gases above the surface of a planet or moon, and what we often call the air biome One of the major regions of the Earth providing particular climatic conditions for plant and animal life—e.g., tropical rainforest, temperate grassland boreal Northern—particularly used to describe northern coniferous forests broadleaved Trees that are not conifers caecilian A type of limbless, wormlike amphibian canine Doglike; describes the teeth behind the incisors in the jaw, usually enlarged as conical stabbing teeth in meat-eaters canopy A layer in a forest formed by the interlocking upper branches of trees carnassial teeth Teeth at the side of a carnivore’s jaw that are adapted to slicing through meat carnivore An animal that eats meat carrion The flesh of dead animals, found rather than killed by the animal eating it cecum The pouch at the start of the large intestine club moss A type of primitive plant, with small living species, that was often tree-sized 300 million years ago coprolite Fossilized waste matter cud Food regurgitated into the mouth from the stomach for a second chewing by a ruminant dehydrated Containing less water than is needed to function properly diaphragm A muscular membrane between the chest and the abdomen in a mammal diapsid A skull with two window-like openings at the sides (other than those openings for eyes, ears, and nose) diversity A number of different animals, or habitats, in an area ecosystem The animals, plants, and other organisms that form an interactive community with their physical surroundings embryo A developing young animal before birth or hatching equilibrium A point of balance erosion The combination of factors—physical and chemical—that break down bedrock until it eventually becomes particles of soil ON THE LAND GLOSSARY Marsupial Mollusk Perissodactyl © DIAGRAM evolution The process of gradual change by which one type of living thing gives rise to another fossil The remains or traces of an ancient organism, preserved in rocks by the geological process of fossilization gastropod A snail or similar mollusk that walks on a muscular “foot,” and has a hard shell over the body gestation period The period between mating and the birth of a young mammal Gondwana The large southern landmass that existed hundreds of millions of years ago, which has since separated into the continents of the Southern Hemisphere herbivore An animal that eats plants hibernate To go into a resting state for the winter hypodermic Beneath the skin A hypodermic syringe injects below the skin igneous Rocks that have been produced by volcanic processes incisor teeth The teeth across the front of the mouth in a mammal insectivore An insect-eater, particularly one of the group of mammals that includes shrews and hedgehogs isopod A crustacean of the group that includes woodlice, and also many freshwater, deep-sea, and parasitic creatures Jacobson’s organ A sense organ in the roof of the mouth of vertebrates that can detect chemicals and odors It is especially well developed in snakes and lizards keratin The chemical that makes up horn, hooves, claws, and hair latitude A measure of distance from the equator mammal A warm-blooded animal that feeds its young on milk Mammals usually have hair marsupial One of the group of mammals that gives birth to very immature young, which are then kept in a pouch of skin on the mother for a while mollusk Invertebrate animal such as a snail or clam, with a soft unsegmented body, usually protected by one or two hard shells monotreme A member of a mammals’ group that lays eggs rather than having young born alive multituberculate A member of an extinct group of plant-eating mammals mummification Preservation of the body by a process of drying nocturnal Active at night omnivore An animal that eats both meat and plants opposable Capable of being placed opposite, like the human thumb to the rest of the fingers ornithischian A dinosaur belonging to the group with “birdlike” hips This group were all plant-eaters palate The roof of the mouth pampas A grass-covered plain in temperate South America parasite An animal that lives on, or inside, another and feeds upon it while the host animal is still alive perissodactyl An animal in the group of hoofed mammals with odd numbers of toes 107 108 Glossary Proboscidean Ratite Ruminant placenta A plate of tissue, through which oxygen and other substances can be exchanged, that joins a baby mammal in the womb to its mother placental A mammal in which the young are nourished inside the mother before birth through a blood-filled organ called the placenta prairie Extensive grassland, especially temperate grassland in North America predator An animal that catches and kills other animals for food primitive An early member of a group of animals, or one showing characteristics believed to be similar to those of early animals proboscidean An elephant, or relative in the same order of mammals, socalled because most have a long nose (proboscis) that helps in feeding pterosaur One of the flying reptiles, with a wing of leathery skin, that lived in the time of the dinosaurs radioactive Elements in which some nuclei spontaneously disintegrate (“decay”), giving off energetic particles ratite A flightless, running bird, such as an ostrich resin A thick liquid, becoming solid, that exudes from trees such as pine, particularly where bark is damaged ruminant An animal with a complex stomach in which the stomach contents are returned to the mouth for a second chewing saurischian A dinosaur belonging to the group with “lizardlike” hips This group included plant-eaters and meat-eaters sauropod A plant-eating dinosaur of the saurischian group that walked on all fours and often grew to great size savanna A tropical grassland sediment The particles deposited by wind or water spinnerets The organs from which spiders produce silk steppe Dry grassland, particularly on the plains of eastern Europe or Asia stratum A layer synapsid A reptile with a single single pair of openings at the sides of the skull Synapsids are extinct, but gave rise to mammals temperate Moderate: used to describe parts of the Earth that not have extreme temperatures terrestrial Living on land territorial An animal that defends a particular area for itself or its group against others of its kind tundra A treeless, cold area with low vegetation in polar regions, or at mountain tops ungulate A hoofed mammal venom Poison produced by an animal for killing prey, or for defense vestige A small relic, or remnant, of an organ that is no longer functional vocal sac A balloonlike organ in the throat that amplifies sound production in frogs Websites to visit 109 There is a lot of useful information on the internet There are also many sites that are fun to use Remember that you may be able to get information on a particular topic by using a search engine such as Google (http://www.google.com) Some of the sites that are found in this way may be very useful, others not Below is a selection of websites related to the material covered by this book Most are illustrated, and they are mainly of the type that provides useful facts Facts On File, Inc takes no responsibility for the information contained within these websites All the sites were accessible as of September 1, 2003 Amphibians Links to many sources on amphibians of all kinds http://www.herper.com/amphibians.html Australian Wildlife: Marsupials An introduction to marsupials http://www.australianwildlife.com.au/features/marsupials.htm BBC Education: Evolution: Extinctions An account of mass extinctions throughout the Earth’s history http://www.bbc.co.uk/education/darwin/exfiles/massintro.htm BBC Walking With Beasts: Fossilization An animated explanation of some fossilization processes http://www.bbc.co.uk/beasts/fossilfun/makingfossils/ Caecilians Photographs and information about caecilians http://www.caecilian.org California Turtle & Tortoise Club Links to various sites about tortoises and turtles http://www.tortoise.org/cttclink.html © DIAGRAM GeoZoo: Mammals An excellent index of introductions to groups of living mammals http://www.geobop.com/Mammals/ 110 Websites to visit Open Directory Project: Paleontology A comprehensive listing of internet resources http://dmoz.org/Science/Earth_Sciences/Paleontology/ Palaeos: Aves Scholarly classification of flightless birds http://www.palaeos.com/Vertebrates/Units/350Aves/900.html Primates.com Photographs and detailed facts about primates http://www.primates.com The Talk Origins Archive: Radiometric Dating and the Geological Time Scale A thorough explanation of how rocks—and hence fossils within—are dated http://www.talkorigins.org/faqs/dating.html UCB, Museum of Paleontology: Biomes Factual website giving information on biomes http://www.ucmp.berkeley.edu/glossary/gloss5/biome/ UCB, Museum of Paleontology: Introduction to Pareiasauria Some information on pareiasaurs, with links to other primitive reptiles http://www.ucmp.berkeley.edu/anapsids/pareiasauria.html University of Manchester, Earth Sciences: Mesozoic Arachnids Fascinating photographs of fossil spiders http://www.earth.man.ac.uk/research/projects/1/site/photos.html University of Michigan, Museum of Zoology: Metatheria Scholarly facts about marsupials http://animaldiversity.ummz.umich.edu/chordata/mammalia/metatheria.html University of Michigan, Museum of Zoology: Monotremes Scholarly facts about egg-laying mammals http://animaldiversity.ummz.umich.edu/chordata/mammalia/monotremata.html Index 111 creodonts 70 cuscuses 53 B bandicoots 51 bears 72 binturong 73 biomes 6–9 birds 86–87, 95 bison 96 brontotheres 74–75 E earthworms 21 echidna 46–47 edentates 58–59 egg-laying mammals 46–47 “elephant birds” 86 elephants 84–85 elk 93 emus 87 extinctions 12–13 C camels 81, 99 capybaras 67 Carboniferous period 18 carnivores 68–73 cassowaries 86–87 cat family 68–73 centipedes 24–25 chameleons 41 cheetahs 95 chevrotains 82 chinchilla 67 chipmunks 64–65 climatic zones 8–9 continents 6–7 coyotes 97 crabs 26 D deer 82 deermouse 66 deserts 98–99 dinosaurs 9, 12–13, 34–37 dog family 68–69, 72 duck-billed platypus 47 F fleas 27 fossil fuels 18–19 fossils 14–17 frogs 28–29 G gaurs 83 geckos 41 gerenuk 94 gibbons 61 giraffes 82–83 goliath beetles 89 gophers 64–65 gorillas 61 grassland 94–97 guinea pigs 66 H hares 63 hedgehogs 56 hoofed mammals 74–81 horses 79, 96 hyenas 73, 95 hyraxes 74–75 I ibex 83 iguanas 40–41 insects 26, 101 isopods 27 J jack rabbit 62 jerboas 66 K kangaroo rats 99 kangaroos 48–49, 52–53 kinkajou 73 kiwis 86–87 koalas 53 Komodo dragon 40 kowaris 51 kudu 82 L lemurs 60 lions 68 litopterns 77 lizards 40–41 © DIAGRAM A aardvarks 75 amphibians 10, 29 ankylosaurs 37 anteaters 58 antelope 97 arachnids 22–23 armadillos 58–59 artiodactyls 80–82 astrapotheres 77 112 Index M mammoths 85 marmots 64–65 marsupials 48–53 mastodonts 84 miacids 71 mice 62, 66 millipedes 24–25 moas 86 moles 56–57 mongooses 73 monkeys 60–61 monotremes 47, 54 moose 82, 92–93 mountains 6–7, 100–101 N notoungulates 76 O oil, formation of 19 okapi 82 ornithischians 36–37 ostriches 86–87 P pandas 72 pangolins 69 peccaries 81 pelycosaurs 33 perissodactyls 78 pig family 80 pikas 63, 101 placental mammals 54–55 porcupines 66–67 possums 53 primates 60–61 pterosaurs 12 pyrotheres 76–77 Q queleas 95 R rabbits 62–63 radiometric dating 16–17 ratites 87 red river hogs 80 reptile, early forms of 10, 32–33 rheas 86–87 rhinoceroses 78–79 rodents 62, 64, 66, 96 roundworms 21 ruminants 81–83 S salamanders 30–31 saurischians 35 scorpions 10, 22–23 shrews 56–57 sloths 58–59 snails 21 snakes 42–43, 98 snow leopards 100 solenodons 57 spider monkey 61 spiders 22–23 springhares 65 squirrels 64–65 stoats 73 striped hyena 73 striped tenrec 57 T tamanduas 59 Tamil loris 60 tapirs 78 tarsiers 61 Tasmanian devil and Tasmanian wolf 50–51 temperature belts thylacines 51 toads 28–29 tortoises 38–39 tree frogs 88 tuataras 39 V Virginia opossum 50 W wombats 52 Y yaks 100–101 Z zebra 79, 94 .. .LIFE ON EARTH ON THE LAND THE DIAGRAM GROUP Life On Earth: On the Land Copyright © 2004 by The Diagram Group Written, edited, and produced by Diagram Visual Information Ltd Editorial... periods Liverwort No life on the land No life on the land © DIAGRAM Millions of years ago 11 12 Mass extinctions Uintatherium (left) A large mammal, it evolved after the extinction of the dinosaurs... looks at the living conditions that animals face on land, and briefly reviews the course of evolution among land animals It also covers the topic of mass extinctions throughout the Earth? ??s history