III. Mesozoic Era A. Triassic Period ( mya)
III. Mesozoic Era A. Triassic Period ( mya) - climate: Dry; low sea levels; one large supercontinent beginning to break up
III. Mesozoic Era A. Triassic Period ( mya) - inverts: - marine communities - gastropods and molluscs begin to dominate in these initially depauperate faunas... the 'modern marine fauna', including modern reef-builders
III. Mesozoic Era A. Triassic Period ( mya) - Plants: - recovery from the mass extinction is slow; lycopsids dominate early, but soil formation is very slow... - dry climate selects for seed plants with pollen; the Gymnosperms... Petrified Forest N. P.
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - Medium sized therapsids dominate early... like Lystrosaurus
Triassic survivors Mammals Gorgonopsids Therapsids Pelycosaurs Dicynodonts Cynodonts
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - Medium sized therapsids dominate early... like Lystrosaurus - Temnospondyls resurgent (Mastodonosaurus - 6m)
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - radiation of the diapsids, but only Ichthyosaurs abundant early Diapsida Younginiformes Ichthyosaurs Lepidosaurs: Lizards, Snakes, Sphenodonts, Plesiosaurs) Archosaurs: Dinosaurs, Pterosaurs, Crocodilians, Birds
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - the opening of the shallow Tethys Sea between Laurasia and Gondwanaland created a very productive marine environment, which was exploited by a diverse group of evolving marine reptiles in the three major diapsid groups:
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - marine reptiles: Ichthyosaurs Placodonts Archeosaurs: Tanystropheus Lepidosaurs: Nothosaurus
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - marine reptiles: Lepidosaurs: Nothosaurus Shonisaurus - 21m (Blue Whale = 33m, 110 ft)
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - As the Triassic proceeds, the Archosaurs displace the Therapsids. Crocodylomorphs (Ornithosuchans and Phytosaurs) Pterosaurs Dinosaurs crucrotarsi Ornithodira (Marasuchas)
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - As the Triassic proceeds, the Archosaurs displace the Therapsids. - Crocodylomorphs:
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - As the Triassic proceeds, the Archosaurs displace the Therapsids. - In the late Triassic, the first Dinosaur radiations occur. Ornithichians Prosauropods Sauropods Theropods Saurichians
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - As the Triassic proceeds, the Archosaurs displace the Therapsids. - In the late Triassic, the first Dinosaur radiations occur. Ornithichians Prosauropods Sauropods Theropods Ornithischians
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - As the Triassic proceeds, the Archosaurs displace the Therapsids. - In the late Triassic, the first Dinosaur radiations occur. Ornithichians Prosauropods Sauropods Theropods Saurischian s
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - As the Triassic proceeds, the Archosaurs displace the Therapsids. - In the late Triassic, the first Dinosaur radiations occur. Oldest Dinosaurs are the Theropod-like Eoraptor
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - As the Triassic proceeds, the Archosaurs displace the Therapsids. - In the late Triassic, the first Dinosaur radiations occur. The first radiation of large dinosaurs were the herbivorous Prosauropods By the late Triassic, all large herbivores were Sauropodomorphs.
III. Mesozoic Era A. Triassic Period ( mya) - Verts: - the first mammaliforms... Morganucodontids
III. Mesozoic Era B. Jurassic ( mya) - Climate: A global greenhouse - lush tropical habitats and rich shallow seas lead to the period of maximum Dinosaur domination.
III. Mesozoic Era B. Jurassic ( mya) - Marine Reptiles: Ichthyosaurs still present...
III. Mesozoic Era B. Jurassic ( mya) - Marine Reptiles: but now joined by Plesiosaurs and Pliosaurs (both Lepidosaurs)
III. Mesozoic Era B. Jurassic ( mya) - Marine Reptiles: and marine crocodylians....
III. Mesozoic Era B. Jurassic ( mya) - Herbivores: Ornithichian Stegosaurs
III. Mesozoic Era B. Jurassic ( mya) - Herbivores: Sauropods - the first of the real giants 1, small head and peg-like teeth (and elongated cervical vertebrae) 2, addition of extra cervical vertebrae to the neck 3, apron-like pubis 4, fore limbs as long as or longer than hind limbs, making the back slope posteriorly 5, teeth restricted to front of mouth 6, armor.
III. Mesozoic Era B. Jurassic ( mya) - Herbivores: Sauropods - the first of the real giants Ultrasaurus (maybe a Brachiosaurus) stood 98 ft long, 140 tons
III. Mesozoic Era B. Jurassic ( mya) - Herbivores: Sauropods - the first of the real giants Diplodocus - 90 ft long 11 tons
III. Mesozoic Era B. Jurassic ( mya) - Carnivores: 1. three-toed foot 2. digits IV and V lost on hand 3. long arms 4. semilunate carpal 5. fused pelvis 6. large hole in lacrimal bone in skull 7. ?no unique derived characters? 8. giant, hook-like claw on digit II of pes 9. flight feathers
III. Mesozoic Era B. Jurassic ( mya) - Carnivores: - Ceratosaurs Ceratosaurus
III. Mesozoic Era B. Jurassic ( mya) - Carnivores: - Carnosaurs Allosaurus
III. Mesozoic Era B. Jurassic ( mya) - Carnivores: - Avialae Archaeopteryx
III. Mesozoic Era B. Jurassic ( mya) - Carnivores: - Avialae Archaeopteryx First fossil a flight feather (asymmetrical)
The 'London' Specimen The 'Berlin' Specimen
10th specimen described in shows intermediately rotated halux
10th specimen described in shows intermediately rotated halux and hyperextended 2nd digit (like Deinonychosaurs - their sister clade)
A. Herrerasaurus- five digits are present, Digit V shaded yellow and hidden on other side of hand. B. Coelophysis. Note that digit V is gone. C. Deinonychus. Note loss of both digits V and IV D. Archaeopteryx. Note very close correspondence in proportions and relative lengths of bones to Deinonychus. E. Hoatzin embryo. Number of bones reduced in digit III. F. Hoatzin adult. Most of the bones of the hand fused Hand Morphology
Ornitholestes (theropod dinosaur) Archaeopteryx Sinornis (a Cretaceous bird) Modern chicken Another Set of Examples Archaeopteryx Chicken
III. Mesozoic Era B. Jurassic ( mya) - Pterosaurs They were present in the Triassic, but reached their greatest diversity in the Jurassic, with over 80 species recorded. However, they would attain their greatest size in the Cretaceous.
III. Mesozoic Era B. Jurassic ( mya) - Pterosaurs They were present in the Triassic, but reached their greatest diversity in the Jurassic, with over 80 species recorded. However, they would attain their greatest size in the Cretaceous.
III. Mesozoic Era B. Jurassic ( mya) - Mammals: Docodonts.... a group of beaver-like animals... the most impressive fossil of the group was found in Feb oldest animal with fur - demonstrates that mammals were radiating into a variety of habitats
III. Mesozoic Era A. Triassic Period ( mya) B. Jurassic ( mya) C. Cretaceous ( mya)
III. Mesozoic Era A. Triassic Period ( mya) B. Jurassic ( mya) C. Cretaceous ( mya) - the warming trend of the Jurassic continues, and results in very high sea levels and the expanse of shallow seas over significant portions of continents
III. Mesozoic Era A. Triassic Period ( mya) B. Jurassic ( mya) C. Cretaceous ( mya) - Plants: Evolution of Angiosperms Initially in low abundance Come to dominate by end of Cretaceous Gymnosperms
III. Mesozoic Era A. Triassic Period ( mya) B. Jurassic ( mya) C. Cretaceous ( mya) - Plants: Evolution of Angiosperms Initially in low abundance Come to dominate by end of Cretaceous Gymnosperms Angiosperms
Archaefructus sinensis Science 2002
III. Mesozoic Era A. Triassic Period ( mya) B. Jurassic ( mya) C. Cretaceous ( mya) - Plants: Evolution of Angiosperms Initially in low abundance Come to dominate by end of Cretaceous Gymnosperms
III. Mesozoic Era A. Triassic Period ( mya) B. Jurassic ( mya) C. Cretaceous ( mya) - Plants: Evolution of Angiosperms Initially in low abundance Come to dominate by end of Cretaceous Gymnosperms
III. Mesozoic Era A. Triassic Period ( mya) B. Jurassic ( mya) C. Cretaceous ( mya) - Inverts: radiation of pollinators radiation of pollinators and herbivores ground beetles do not
C. Cretaceous - Verts: -Crocodylians Sarcosuchus 11m
C. Cretaceous ( mya) - Inverts: - Verts: Ornithischians: Stegosaurs give way to a variety of new Ornithischian groups:
Ornithischians: Ankylosaurs
Ornithischians: Ceratopsians
Ornithischians: Iguanodonts
Ornithischians: Hadrosaurs
Ornithischians: Pachycephalosaurs
C. Cretaceous ( mya) - Inverts: - Verts: Ornithischians: Saurischians - Sauropods The Titanosaurs (and they were still big)
The Titanosaurs Andesaurus 40m (?) 80 tons (?) incomplete skeleton
The Titanosaurs Argentinasaurus Largest one known with confidence, but there are bigger single bones m tons incomplete skeleton but a hip girdle, vertebrae, and tibia
C. Cretaceous - Theropods: carnivores get big!! Carnosaurs - Giant Allosaur cousins like: Giganotosaurus Longer than the largest Tyrannosaurus rex by 2m ft... from Argentina (1995)
C. Cretaceous Carnosaurs - Giant Allosaur cousins like: Carcharodontosaurus 40 ft - slightly smaller than T. rex from Niger (1927)
C. Cretaceous Carnosaurs - Tyrannosaurs: - Albertosaurus
C. Cretaceous Carnosaurs - Tyrannosaurs: - Gorgosaurus
C. Cretaceous Carnosaurs - Tyrannosaurs: - Tyrannosaurus (3 sp.)
C. Cretaceous Carnosaurs - Tyrannosaurs: - Tyrannosaurus (3 sp.)
C. Cretaceous Carnosaurs - Tyrannosaurs: - Tyrannosaurus (3 sp.) Soft tissue from a femur? Yup! t-rex-soft-tissue.html
C. Cretaceous Carnosaurs - Tyrannosaurs: - Dilong paradoxicus Feathered
C. Cretaceous Carnosaurs - Tyrannosaurs: - Spinosaurs - Spinosaurus – largest land carnivore? ft?
C. Cretaceous - Deinonychians Deinonychus Velaciraptor
III. Mesozoic C. Cretaceous - theropods (still) - Deinonychians Velociraptor
C. Cretaceous - non-bird feathered dinosaurs: Sinosauropteryx prima (1996) first non-bird dinosaur with feathers... a Cretaceous contemporary of birds
- Protobirds
- Protobirds: Sinornithosaurus (Jurassic)
- Protobirds: Microraptor (Cretaceous)
Protobirds: - Deinonychians Velociraptor
- Protobirds: Unenlagia (Cretaceous)
- Protobirds: Caudipterxy (Cretaceous)
- Protobirds: Protarchaeopteryx (Cretaceous)
- Protobirds: Eoalulavis (Cretaceous)
- Pterosaurs:
Pteranodon - wingspan 7.5 m
- Pterosaurs: Quetzalcoatlus - largest ptersaur; 40 ft wingspan....
- Quetzalcoatlus - largest flying animal Quetzalcoatlus - largest ptersaur; 40 ft wingspan....
- Mammals...
- Multituberculates Dominate in Cretaceous - over 200 species
The K-T Boundary
hmm... a new star in the constellation of Orion... THAT'S weird...
The K-T Boundary
WHAT THE HELL!!! It's the Ceratopsians... they're attacking...!!!
The K-T Boundary