Life in the Mesozoic

The Age of Dinosaurs

Mesozoic Life Highlights

• Oceans repopulated with “Modern Fauna”

• Dominant land animals - Dinosaurs• First Flowering Plants & Social Insects

• First Mammals• First Birds• Two Mass Extinctions(end-Triassic and end-Cretaceous)

What’s Happening in the Oceans?

PhytoplanktonErupt

Paleozoic vs. Mesozoic

Rugosa & Tabulata Corals

Hexacorals

Reefs - Hexacorals

Reefs - Rudists

Paleozoic vs. Mesozoic

Brachiopods Bivalves & Gastropods

Inoceramids

Paleozoic vs. Mesozoic

Crinoids Echinoids (Sea Urchins)

Paleozoic vs. Mesozoic

Trilobites Crustaceans

Life was Adapting to Major Marine Predators

Ammanoids - Parapuzosia

Bony Fish - Xiphactinus

Marine Reptiles

Placodonts

Plesiosaurs:

Elasmosaurus

Kronosaurus

Ichthyosaurus

Mosasaurus

Largest-150 ft long!

Marine Reptile Relatio

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Giant Sea Turtles

The “Green Report”

Flower Power Add Color to the Earth

Angiosperms

First Flowers

Magnolia

Cretaceous Flower

Flowers and Insects

Cretaceous

Paleozoic vs. Mesozoic

Large Amphibians Frogs and Salamanders

Paracyclotosaurus

Triassic Frogs

Mesozoic Reptiles

Synapsids(Mammals)

Anapsids(Turtles)

Diapsids

Lizards& Snakes

Crocodiles

Pterosaurs

MarineReptiles

Dinosaurs& Birds

Archosaurs

Archosaurs:

Early Diapsids

Big Dinosaur Questions

• What are Dinosaurs?• How do we understand Dinosaur behavior?

• Where dinosaurs warm-blooded (endotherms) or cold-blooded (ectotherms)?

• Did birds evolve from dinosaurs?• What caused the extinction of the dinosaurs?

Dinosaurs vs. “Reptiles”

1.Upright posture Legs beneath the body rather than to the side

2.Unique arrangement of ankle hinge (and other skeletal differences)

The 2 Major Lines of Dinosaurs

Critters Gallery

critters.pixel-shack.com

Russel Gooday & John Hughes

Ornithischia“Bird-Hipped Dinosaurs”

1.Stegosaurs2.Hadrosaurs3.Ankylosaurs4.Pachycephalosaurs5.Ceratopsids

All Herbivores

Hadrosaurs - “Duck-billed Dinosaurs”

Ouranosaurus

Hadrosaurs

Parasauralophus

Hadrosaurs

Maiasaurus

Laellynasaura

Stegosaurs

Stegosaurus

Ankylosaurids - Natures Tanks

Euoplocephalus

Ankylosaurids

ankylosaurus

Pachycephalosaurs - “Bone Heads”

Pachycephalosaurus

Ceratopsids

“Horned Dinos”

Torosaurus

Ceratopsids

Triceratops