SlideShare a Scribd company logo
1 of 8
Different kinds of Dinosaurs
       • Two main
         groups:
            – Saurischia
              (reptile-hipped)
            – Ornithischia
              (bird-hipped)



                                     Above: Edmontosaurus
     Left: Tyrannosaurus pelvis
                                     pelvis showing
     showing saurischian structure
                                     ornithischian structure
Saurischia: Theropods
• Two-legged meat eaters
• Evolved into birds!
Saurischia: Sauropodomorphs

• HUGE four-legged
  plant eaters with long
  necks and tails
Ornithischia: Ornithopods
• Two or four-legged
  plant eaters




                            cc. Arthur Weasley
Ornithischia: Ceratopsians, Ankylosaurs
            and Stegosaurs
• Four-legged plant eaters
  with pointy, knobbly bits!
Other animals in Mesozoic times…
 • In Mesozoic skies
   – Pterosaurs (Flying reptiles)




     cc. Arthur Weasley
Other animals in Mesozoic times…
 • In Mesozoic seas
   – Ichthyosaurs, Plesiosaurs, Mosasaurs




                                         cc. Fritz Geller-Grimm




                                        cc. Arthur Weasley
               cc. Arthur Weasley
Other animals in Mesozoic times…
 • Small Mammals

More Related Content

What's hot

Dinosaurs types
Dinosaurs typesDinosaurs types
Dinosaurs typesjoseklo
 
different primates all over the world
different primates all over the worlddifferent primates all over the world
different primates all over the worldKing_cute
 
Classification of mammals, M. Sc, Zoology, University of Mumbai.
Classification of mammals, M. Sc, Zoology, University of Mumbai.Classification of mammals, M. Sc, Zoology, University of Mumbai.
Classification of mammals, M. Sc, Zoology, University of Mumbai.Royston Rogers
 
Presentation on mammal`s
Presentation on mammal`sPresentation on mammal`s
Presentation on mammal`sHabibur Rahman
 
Reptiles 10-2 lora miro alexander
Reptiles 10-2 lora miro alexanderReptiles 10-2 lora miro alexander
Reptiles 10-2 lora miro alexanderMrJewett
 
Mesozoic Era, Dinosaurs, K-T Mass Extinction Event, Earth Science Lesson Powe...
Mesozoic Era, Dinosaurs, K-T Mass Extinction Event, Earth Science Lesson Powe...Mesozoic Era, Dinosaurs, K-T Mass Extinction Event, Earth Science Lesson Powe...
Mesozoic Era, Dinosaurs, K-T Mass Extinction Event, Earth Science Lesson Powe...www.sciencepowerpoint.com
 
Dinosaur face offs digital book
Dinosaur face offs digital bookDinosaur face offs digital book
Dinosaur face offs digital bookAnnmarie1020
 
Diversity In Living Organisms (Animalia)
Diversity In Living Organisms (Animalia)Diversity In Living Organisms (Animalia)
Diversity In Living Organisms (Animalia)Malthip
 
Dinosaur Ppt Project
Dinosaur Ppt ProjectDinosaur Ppt Project
Dinosaur Ppt Projectakrafft16
 
Dinosaurs
DinosaursDinosaurs
Dinosaursrieker9
 
Dinosaurs
DinosaursDinosaurs
Dinosaurscetatum
 
Primate Evolution
Primate EvolutionPrimate Evolution
Primate Evolutionnadpat05
 
Early Human Notes
Early Human NotesEarly Human Notes
Early Human Notesjsimoni1
 

What's hot (20)

Dinosaurs
DinosaursDinosaurs
Dinosaurs
 
Dinosaurs types
Dinosaurs typesDinosaurs types
Dinosaurs types
 
different primates all over the world
different primates all over the worlddifferent primates all over the world
different primates all over the world
 
Classification of mammals, M. Sc, Zoology, University of Mumbai.
Classification of mammals, M. Sc, Zoology, University of Mumbai.Classification of mammals, M. Sc, Zoology, University of Mumbai.
Classification of mammals, M. Sc, Zoology, University of Mumbai.
 
Hallie
HallieHallie
Hallie
 
Presentation on mammal`s
Presentation on mammal`sPresentation on mammal`s
Presentation on mammal`s
 
Dinosaurs
DinosaursDinosaurs
Dinosaurs
 
Reptiles 10-2 lora miro alexander
Reptiles 10-2 lora miro alexanderReptiles 10-2 lora miro alexander
Reptiles 10-2 lora miro alexander
 
Mesozoic Era, Dinosaurs, K-T Mass Extinction Event, Earth Science Lesson Powe...
Mesozoic Era, Dinosaurs, K-T Mass Extinction Event, Earth Science Lesson Powe...Mesozoic Era, Dinosaurs, K-T Mass Extinction Event, Earth Science Lesson Powe...
Mesozoic Era, Dinosaurs, K-T Mass Extinction Event, Earth Science Lesson Powe...
 
Dinosaur face offs digital book
Dinosaur face offs digital bookDinosaur face offs digital book
Dinosaur face offs digital book
 
A presentation on dinosaurs
A presentation on dinosaursA presentation on dinosaurs
A presentation on dinosaurs
 
Diversity In Living Organisms (Animalia)
Diversity In Living Organisms (Animalia)Diversity In Living Organisms (Animalia)
Diversity In Living Organisms (Animalia)
 
Dinosaur Ppt Project
Dinosaur Ppt ProjectDinosaur Ppt Project
Dinosaur Ppt Project
 
Dinosaurs
DinosaursDinosaurs
Dinosaurs
 
Dinosaurs
DinosaursDinosaurs
Dinosaurs
 
Primate Evolution
Primate EvolutionPrimate Evolution
Primate Evolution
 
Dinosaurs ppt with info
Dinosaurs ppt with infoDinosaurs ppt with info
Dinosaurs ppt with info
 
Dinosaur Facts Ppt
Dinosaur Facts PptDinosaur Facts Ppt
Dinosaur Facts Ppt
 
Dinosaurs
DinosaursDinosaurs
Dinosaurs
 
Early Human Notes
Early Human NotesEarly Human Notes
Early Human Notes
 

Similar to Dinosaurs1a (20)

Animalia...
Animalia...Animalia...
Animalia...
 
Taxonomy
TaxonomyTaxonomy
Taxonomy
 
Dinosaur and their extinction
Dinosaur and their extinctionDinosaur and their extinction
Dinosaur and their extinction
 
5 Primates
5 Primates5 Primates
5 Primates
 
ORIGIN MAMMALS.pptx
ORIGIN MAMMALS.pptxORIGIN MAMMALS.pptx
ORIGIN MAMMALS.pptx
 
Hexapoda
HexapodaHexapoda
Hexapoda
 
Invertebrates_Edtech101
Invertebrates_Edtech101Invertebrates_Edtech101
Invertebrates_Edtech101
 
Animal kingdom
Animal kingdomAnimal kingdom
Animal kingdom
 
Classification.ppt
Classification.pptClassification.ppt
Classification.ppt
 
Origin and Evolution of Mammals
Origin and Evolution of MammalsOrigin and Evolution of Mammals
Origin and Evolution of Mammals
 
World of insects
World of insectsWorld of insects
World of insects
 
Early Reptiles : Dinosaurs
Early Reptiles : DinosaursEarly Reptiles : Dinosaurs
Early Reptiles : Dinosaurs
 
Entomology
EntomologyEntomology
Entomology
 
Sauropods
SauropodsSauropods
Sauropods
 
Animals throughout the world
Animals throughout the worldAnimals throughout the world
Animals throughout the world
 
Origin and Evolution of Mammals.pptx
Origin and Evolution of Mammals.pptxOrigin and Evolution of Mammals.pptx
Origin and Evolution of Mammals.pptx
 
'The Big Lizards’
'The Big Lizards’'The Big Lizards’
'The Big Lizards’
 
Mammals
MammalsMammals
Mammals
 
Dinosaurs
DinosaursDinosaurs
Dinosaurs
 
The vertebrates
The vertebratesThe vertebrates
The vertebrates
 

More from angelabentley

Hydrographs tcm4 134116
Hydrographs tcm4 134116Hydrographs tcm4 134116
Hydrographs tcm4 134116angelabentley
 
The hydrological cycle
The hydrological cycleThe hydrological cycle
The hydrological cycleangelabentley
 
Organic chemical sedimentary_rockssmall
Organic chemical sedimentary_rockssmallOrganic chemical sedimentary_rockssmall
Organic chemical sedimentary_rockssmallangelabentley
 
Sedimentary structures smallas
Sedimentary structures smallasSedimentary structures smallas
Sedimentary structures smallasangelabentley
 
Sedimentary structures smallas
Sedimentary structures smallasSedimentary structures smallas
Sedimentary structures smallasangelabentley
 
Metamorphismpptpntn.ppt2
Metamorphismpptpntn.ppt2Metamorphismpptpntn.ppt2
Metamorphismpptpntn.ppt2angelabentley
 
Clastic sedimentary rockssmall
Clastic sedimentary rockssmallClastic sedimentary rockssmall
Clastic sedimentary rockssmallangelabentley
 
Classifying igneous rocks
Classifying igneous rocksClassifying igneous rocks
Classifying igneous rocksangelabentley
 

More from angelabentley (20)

AS Geology mapping
AS  Geology mappingAS  Geology mapping
AS Geology mapping
 
Dinosaurfootprints
DinosaurfootprintsDinosaurfootprints
Dinosaurfootprints
 
Dinosaursmodeoflife
DinosaursmodeoflifeDinosaursmodeoflife
Dinosaursmodeoflife
 
Hydrographs tcm4 134116
Hydrographs tcm4 134116Hydrographs tcm4 134116
Hydrographs tcm4 134116
 
The hydrological cycle
The hydrological cycleThe hydrological cycle
The hydrological cycle
 
Fossils
FossilsFossils
Fossils
 
Glacial landforms2
Glacial landforms2Glacial landforms2
Glacial landforms2
 
Glacial landforms
Glacial landformsGlacial landforms
Glacial landforms
 
Glacial features
Glacial featuresGlacial features
Glacial features
 
Organic chemical sedimentary_rockssmall
Organic chemical sedimentary_rockssmallOrganic chemical sedimentary_rockssmall
Organic chemical sedimentary_rockssmall
 
Sedimentary structures smallas
Sedimentary structures smallasSedimentary structures smallas
Sedimentary structures smallas
 
Sedimentary structures smallas
Sedimentary structures smallasSedimentary structures smallas
Sedimentary structures smallas
 
Metamorphismpptpntn.ppt2
Metamorphismpptpntn.ppt2Metamorphismpptpntn.ppt2
Metamorphismpptpntn.ppt2
 
Metamorphism intro
Metamorphism introMetamorphism intro
Metamorphism intro
 
Lava textures
Lava texturesLava textures
Lava textures
 
Igneousrockssmall
IgneousrockssmallIgneousrockssmall
Igneousrockssmall
 
Graphiclogs
GraphiclogsGraphiclogs
Graphiclogs
 
Graphiclogs
GraphiclogsGraphiclogs
Graphiclogs
 
Clastic sedimentary rockssmall
Clastic sedimentary rockssmallClastic sedimentary rockssmall
Clastic sedimentary rockssmall
 
Classifying igneous rocks
Classifying igneous rocksClassifying igneous rocks
Classifying igneous rocks
 

Recently uploaded

Advanced Test Driven-Development @ php[tek] 2024
Advanced Test Driven-Development @ php[tek] 2024Advanced Test Driven-Development @ php[tek] 2024
Advanced Test Driven-Development @ php[tek] 2024Scott Keck-Warren
 
Maximizing Board Effectiveness 2024 Webinar.pptx
Maximizing Board Effectiveness 2024 Webinar.pptxMaximizing Board Effectiveness 2024 Webinar.pptx
Maximizing Board Effectiveness 2024 Webinar.pptxOnBoard
 
How to Remove Document Management Hurdles with X-Docs?
How to Remove Document Management Hurdles with X-Docs?How to Remove Document Management Hurdles with X-Docs?
How to Remove Document Management Hurdles with X-Docs?XfilesPro
 
Unblocking The Main Thread Solving ANRs and Frozen Frames
Unblocking The Main Thread Solving ANRs and Frozen FramesUnblocking The Main Thread Solving ANRs and Frozen Frames
Unblocking The Main Thread Solving ANRs and Frozen FramesSinan KOZAK
 
Injustice - Developers Among Us (SciFiDevCon 2024)
Injustice - Developers Among Us (SciFiDevCon 2024)Injustice - Developers Among Us (SciFiDevCon 2024)
Injustice - Developers Among Us (SciFiDevCon 2024)Allon Mureinik
 
Neo4j - How KGs are shaping the future of Generative AI at AWS Summit London ...
Neo4j - How KGs are shaping the future of Generative AI at AWS Summit London ...Neo4j - How KGs are shaping the future of Generative AI at AWS Summit London ...
Neo4j - How KGs are shaping the future of Generative AI at AWS Summit London ...Neo4j
 
Understanding the Laravel MVC Architecture
Understanding the Laravel MVC ArchitectureUnderstanding the Laravel MVC Architecture
Understanding the Laravel MVC ArchitecturePixlogix Infotech
 
How to convert PDF to text with Nanonets
How to convert PDF to text with NanonetsHow to convert PDF to text with Nanonets
How to convert PDF to text with Nanonetsnaman860154
 
08448380779 Call Girls In Diplomatic Enclave Women Seeking Men
08448380779 Call Girls In Diplomatic Enclave Women Seeking Men08448380779 Call Girls In Diplomatic Enclave Women Seeking Men
08448380779 Call Girls In Diplomatic Enclave Women Seeking MenDelhi Call girls
 
Integration and Automation in Practice: CI/CD in Mule Integration and Automat...
Integration and Automation in Practice: CI/CD in Mule Integration and Automat...Integration and Automation in Practice: CI/CD in Mule Integration and Automat...
Integration and Automation in Practice: CI/CD in Mule Integration and Automat...Patryk Bandurski
 
#StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024
#StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024#StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024
#StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024BookNet Canada
 
Making_way_through_DLL_hollowing_inspite_of_CFG_by_Debjeet Banerjee.pptx
Making_way_through_DLL_hollowing_inspite_of_CFG_by_Debjeet Banerjee.pptxMaking_way_through_DLL_hollowing_inspite_of_CFG_by_Debjeet Banerjee.pptx
Making_way_through_DLL_hollowing_inspite_of_CFG_by_Debjeet Banerjee.pptxnull - The Open Security Community
 
Slack Application Development 101 Slides
Slack Application Development 101 SlidesSlack Application Development 101 Slides
Slack Application Development 101 Slidespraypatel2
 
Snow Chain-Integrated Tire for a Safe Drive on Winter Roads
Snow Chain-Integrated Tire for a Safe Drive on Winter RoadsSnow Chain-Integrated Tire for a Safe Drive on Winter Roads
Snow Chain-Integrated Tire for a Safe Drive on Winter RoadsHyundai Motor Group
 
Transforming Data Streams with Kafka Connect: An Introduction to Single Messa...
Transforming Data Streams with Kafka Connect: An Introduction to Single Messa...Transforming Data Streams with Kafka Connect: An Introduction to Single Messa...
Transforming Data Streams with Kafka Connect: An Introduction to Single Messa...HostedbyConfluent
 
Transcript: #StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024
Transcript: #StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024Transcript: #StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024
Transcript: #StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024BookNet Canada
 
Breaking the Kubernetes Kill Chain: Host Path Mount
Breaking the Kubernetes Kill Chain: Host Path MountBreaking the Kubernetes Kill Chain: Host Path Mount
Breaking the Kubernetes Kill Chain: Host Path MountPuma Security, LLC
 
Install Stable Diffusion in windows machine
Install Stable Diffusion in windows machineInstall Stable Diffusion in windows machine
Install Stable Diffusion in windows machinePadma Pradeep
 

Recently uploaded (20)

Advanced Test Driven-Development @ php[tek] 2024
Advanced Test Driven-Development @ php[tek] 2024Advanced Test Driven-Development @ php[tek] 2024
Advanced Test Driven-Development @ php[tek] 2024
 
Maximizing Board Effectiveness 2024 Webinar.pptx
Maximizing Board Effectiveness 2024 Webinar.pptxMaximizing Board Effectiveness 2024 Webinar.pptx
Maximizing Board Effectiveness 2024 Webinar.pptx
 
How to Remove Document Management Hurdles with X-Docs?
How to Remove Document Management Hurdles with X-Docs?How to Remove Document Management Hurdles with X-Docs?
How to Remove Document Management Hurdles with X-Docs?
 
Unblocking The Main Thread Solving ANRs and Frozen Frames
Unblocking The Main Thread Solving ANRs and Frozen FramesUnblocking The Main Thread Solving ANRs and Frozen Frames
Unblocking The Main Thread Solving ANRs and Frozen Frames
 
E-Vehicle_Hacking_by_Parul Sharma_null_owasp.pptx
E-Vehicle_Hacking_by_Parul Sharma_null_owasp.pptxE-Vehicle_Hacking_by_Parul Sharma_null_owasp.pptx
E-Vehicle_Hacking_by_Parul Sharma_null_owasp.pptx
 
Injustice - Developers Among Us (SciFiDevCon 2024)
Injustice - Developers Among Us (SciFiDevCon 2024)Injustice - Developers Among Us (SciFiDevCon 2024)
Injustice - Developers Among Us (SciFiDevCon 2024)
 
Neo4j - How KGs are shaping the future of Generative AI at AWS Summit London ...
Neo4j - How KGs are shaping the future of Generative AI at AWS Summit London ...Neo4j - How KGs are shaping the future of Generative AI at AWS Summit London ...
Neo4j - How KGs are shaping the future of Generative AI at AWS Summit London ...
 
Understanding the Laravel MVC Architecture
Understanding the Laravel MVC ArchitectureUnderstanding the Laravel MVC Architecture
Understanding the Laravel MVC Architecture
 
How to convert PDF to text with Nanonets
How to convert PDF to text with NanonetsHow to convert PDF to text with Nanonets
How to convert PDF to text with Nanonets
 
08448380779 Call Girls In Diplomatic Enclave Women Seeking Men
08448380779 Call Girls In Diplomatic Enclave Women Seeking Men08448380779 Call Girls In Diplomatic Enclave Women Seeking Men
08448380779 Call Girls In Diplomatic Enclave Women Seeking Men
 
Integration and Automation in Practice: CI/CD in Mule Integration and Automat...
Integration and Automation in Practice: CI/CD in Mule Integration and Automat...Integration and Automation in Practice: CI/CD in Mule Integration and Automat...
Integration and Automation in Practice: CI/CD in Mule Integration and Automat...
 
#StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024
#StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024#StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024
#StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024
 
Making_way_through_DLL_hollowing_inspite_of_CFG_by_Debjeet Banerjee.pptx
Making_way_through_DLL_hollowing_inspite_of_CFG_by_Debjeet Banerjee.pptxMaking_way_through_DLL_hollowing_inspite_of_CFG_by_Debjeet Banerjee.pptx
Making_way_through_DLL_hollowing_inspite_of_CFG_by_Debjeet Banerjee.pptx
 
Slack Application Development 101 Slides
Slack Application Development 101 SlidesSlack Application Development 101 Slides
Slack Application Development 101 Slides
 
Snow Chain-Integrated Tire for a Safe Drive on Winter Roads
Snow Chain-Integrated Tire for a Safe Drive on Winter RoadsSnow Chain-Integrated Tire for a Safe Drive on Winter Roads
Snow Chain-Integrated Tire for a Safe Drive on Winter Roads
 
Transforming Data Streams with Kafka Connect: An Introduction to Single Messa...
Transforming Data Streams with Kafka Connect: An Introduction to Single Messa...Transforming Data Streams with Kafka Connect: An Introduction to Single Messa...
Transforming Data Streams with Kafka Connect: An Introduction to Single Messa...
 
Transcript: #StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024
Transcript: #StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024Transcript: #StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024
Transcript: #StandardsGoals for 2024: What’s new for BISAC - Tech Forum 2024
 
Breaking the Kubernetes Kill Chain: Host Path Mount
Breaking the Kubernetes Kill Chain: Host Path MountBreaking the Kubernetes Kill Chain: Host Path Mount
Breaking the Kubernetes Kill Chain: Host Path Mount
 
Install Stable Diffusion in windows machine
Install Stable Diffusion in windows machineInstall Stable Diffusion in windows machine
Install Stable Diffusion in windows machine
 
Vulnerability_Management_GRC_by Sohang Sengupta.pptx
Vulnerability_Management_GRC_by Sohang Sengupta.pptxVulnerability_Management_GRC_by Sohang Sengupta.pptx
Vulnerability_Management_GRC_by Sohang Sengupta.pptx
 

Dinosaurs1a

Editor's Notes

  1. There are over 950 known species of dinosaur!! These can be divided into two groups: The SAURISCHIA (reptile hipped) dinosaurs - the flesh-eating THEROPODS and the long necked (usually large) plant-eating SAUROPODOMORPHS The ORNITHISCHIA (bird hipped) dinosaurs - all plant-eaters, including the two-legged ORNITHOPODS and the various armoured forms
  2. Theropods ranged in size from animals like Compsognathus, the size of a turkey, to the awesome Tyrannosaurus rex, weighing five tonnes or more - the largest meat-eating animal ever; the largest biped - just imagine the biggest elephant balanced up on two legs! They all ate meat, using their sharp teeth to tear the flesh. The teeth kept growing, so if a few snapped off, more grew up from below. They could grab and grapple with prey with their hands.
  3. The first sauropodomorphs were the prosauropods, known from the Late Triassic and Early Jurassic - such as Plateosaurus. These ranged from human-sized up to 7 metres long. Replaced by sauropods in the Early and Middle Jurassic - these were the real giants, some up to 30 metres (100 feet) long, and weighing 50 tonnes - such as Diplodocus, Apatosaurus, and the tall Brachiosaurus. Picture shows Diplodocus.
  4. Ornithoipods were all bipeds and all plant-eaters. Known from Early Jurassic to end of Cretaceous. The early ones, like Heterodontosaurus, were quite small. Early Cretaceous forms included Hypsilophodon (bottom right) and the large Iguanodon with its thumb spike. In the Late Cretaceous, hadrosaurs (duckbills) dominated - with huge herds of these 5-10 metre long dinosaurs munching aeverything thewy saw. They had multiple banks of teeth, up to 500 per jaw (2000 in all). Head crest of Parasaurolophus (left) is not a snorkel, but used as a resonating chamber - its breathing tubes ran up from the nostrils to the tip of the crest, and down the throat. Could puff air out through this making honking noise. Purpose: ?species recognition, mating? Males, females and juveniles all probably honked and tooted at different pitches.
  5. The armoured dinosaurs: Ceratopsians = ‘horned faces’ like Triceratops Ankylosaurs (knobbly skins and tail clubs - shown here) Stegosaurs such as Stegosaurus (plated backs) Best known from Jurassic (esp. stegosaurs) and Cretaceous (esp. ankylosaurs, ceratopsians)
  6. Pterosaurs are sometimes referred to in the popular media as dinosaurs , but this is incorrect. The term "dinosaur" is exclusively restricted to terrestrial reptiles with a unique upright stance (the superorder Dinosauria), and therefore excludes the pterosaurs Pterosaurs had their wing supported along the back of the arm and the extended fourth finger Their skin was covered with short hairs, especially over the back, so fully warm-blooded (high metabolic rate needed for flight) Could fly properly, just like a bird or bat We know they had a flight membrane - often preserved in exceptional specimens, made of elastic, strengthened skin
  7. These are also not dinosaurs, the marine reptiles: ichthyosaurs , plesiosaurs , and mosasaurs Three ichthyosaurs shown here (one fossil, top right) and two reconstructions (top left, bottom right). Huge eyes (vision in murky water), dolphin-like body, swam bt lateral beating of tail and body, and steered with paddles (modified legs). Produced live young at sea. Plesiosaurs (bottom left) had long necks (plesiosauroids) or short necks (pliosaurs; shown here). They came out on to land to lay eggs. Origin of Loch Ness Monster stories?
  8. The first mammals arose about 220 million years ago, about the time of the first dinosaurs Remained small, shrew-sized insect-eaters through the Mesozoic Some larger ones towards the end of the Cretaceous - maybe cat- or badger-sized