Archosauromorphs include the extinct Sauropterygia and the living Testudines
Archosaurs include the Crocodylomorpha, Pterosauromorpha, and Dinosauromorpha
Dinosaurs are not extinct!
Still 10,000 species alive
…
Summary
Archosauromorphs include
extinct Sauropterygia and the living Testudines
Summary
Archosaurs include the
Crocodylomorpha, Pterosauromorpha, and Dinosauromorpha
Summary
Dinosaurs are not extinct!
Still 10,000 species alive
What is a reptile
Previous deck
Archosaurs
3 points
- Arose in the Early Triassic period, 250 Mya
- Definition
The clade that includes the most recent common ancestor of living birds and crocodilians
Pseudosuchia: crocodiles and their extinct relatives
Pterosauromorpha: pterosaurs
Dinosauromorpha: dinosaurs, including birds
- more inclusive Archosauromorpha
Sauropterygia: plesiosaurs and pliosaurs
Testudines: turtles and tortoises
What is an archosaur?
7 points
- A sauropsid amniote
- Sauropsida
- Parasagittal gait
- Reduction / loss of sternum
- Thecodont dentition [teeth fit in to sockets]
- Single penis
- Bony scutes derived from the dermis
Sauropterygia [division from Archosauromorpha]
3 points
- Extinct taxon of aquatic reptiles, dating from approx. 250 Mya
- Descended from terrestrial ancestor
- Two main body forms
Plesiosauromorph: long neck, small head [smaller prey e.g. small fish]
Pliosauromorph: short neck, large head [larger prey]
These are no longer considered taxonomic
Testudines [division from Archosauromorpha]
3 points
- Turtles, tortoises, terrapins (L. “tortoises”)
- Exact affinities are uncertain
Originally placed as descending from basal amniote ancestor
Now known to be diapsids, and more related to archosaurs than lepidosauriformes [controversy about this] (snakes and lizards)
- Shell composed of a carapace (upper) and plastron (belly)
Carapace composed of vertebrae, ribs and possibly scapulae [shoulder?] and pelvis
Supported by cartilage
May be covered in skin scutes / scales made of keratin
Pseudosuchia [division of crocodylomorpha]
- All living crocodilians and all archosaurs more closely related to them than birds
- Wide range of forms; dominant vertebrates in some eras [large variety of different forms]
Crocodilia [division of psuedosuchia]
7 points
- Arose 83.5 Mya [mid to end of dinasours]
- 1-7 metres long, elongated snouts and [laterally] flattened tails
- Adaptions for amphibious lifestyle [eyes on top of head (in water)]
- 2 gaits
Low walk with sprawling limbs [evolved to live in shallow water. Eating terrestrial animals]
High walk for speed [when want to run. Parasatgital gait. Turn elbows in]
- Alligatoridae: 8 species of alligators and caimans
- Crocodylidae: 14 species of crocodiles
- Gavialidae: 1 species of gharial
Ornithodira
[division from archosauromorpha]
3 points
- Characterised by an advanced ankle allowing for better mobility
- Ancestrally upright and bipedal posture
- Two divisions
Pterosauromorpha
Dinosauromorpha
Pterosauromorpha [division of Ornithodira]
4 points
- Earliest vertebrates to develop winged flight 228 – 66 Mya
- Elongated 4th finger and membrane of skin?
- Covered in hair-like filaments called pycnofibres [makes us think they are warm blooded. Need a lot of energy to fly which cant be produced by cold blooded]
- Wide variety of ecological niches
Terrestrial predators of vertebrates
Insectivores
Piscivores, either aerial dip
feeders or plunge-divers
Filter feeders (akin to flamingos)
Dinosauria
4 points
- Slightly more restrictive grouping than the
- Highly diverse group including the largest and (one of) the smallest non-marine vertebrates
- Active animals with elevated metabolisms and adaptations for social interactions
- Ancestrally bipedal
Ornithischia [division of diosauromorpha]
3 points
- Adaptations of jaw for herbivorous diet
Predentary bone [main jaw bone in most amniotes. Front of jaw.]
Toothless premaxillary bone for the attachment of a beak
- Thyreophora
Stegosauria
Ankylosaura - Neornithischia
Ornithopoda
Pachycephalosauria
Ceratopsia
just remember that birds are put in group with
lizard like hips. Point of confusion]
Sauropodomorpha [ division of dinosauromorpha]
4 points
- Long-necked herbivorous dinosaurs, include largest ever land animals
- Early “prosauropods” could be bipedal
- Small skull on long neck
May have had a beak
Some believe they might have had a proboscis (like an elephant’s trunk)
- Two major radiations
Diplocodoidea: Apatosaurus, Diplodocus, etc.
Macronaria: Brachiosaurus, Camarosaurus, etc.
Theropoda [ division of dinosauromorpha]
5 points
- Crown group that includes all descendants of the common ancestor of Herrerasaurus and Passer
- “lizard-hipped”
- Ancestrally carnivorous and bipedal
- Supinated hands (clapping, not playing the piano) [unable to turn wrists. Palms not down. Not using to walk]
- Feathers
In non-coelurosaurs possibly confined to the young or certain body areas
Aves (birds) [ division of therpoa
6 points
- Warm blooded
- Toothless beaks
Feathers - Hard shelled eggs
- Four-chambered heart
- Flight (ancestral)
- Complex behaviour
