Images for Chapter 11 The Triassic Takeover

Diapsids

• Cladogram of diapsids. Figure 11.1.

Basal Diapsids

Lepidosauromorphs

• Squamata are the numerous and diverse smaller living reptiles, including lizards and snakes. Lizard skulls at the University of Texas CT scanning lab, with many more ready to browse.
• Sphenodontia are a sister group of the Squamata but include only one family with one living form, the tuatara Sphenodon.
  • Tuatara drawing from Lydekker. Figure 11.3.
  • Photo of living tuatara
  • Closeup of living tuatara

Archosauromorphs

Mesosaurus

• Drawing of Mesosaurus. Figure 11.5.
• Mesosaurus
• Another specimen of Mesosaurus
• Mesosaurus. South African Museum.
• Reconstruction of Mesosaurus.

The Triassic Diapsid Takeover

Respiration, Metabolism, and Locomotion

• Amniote postures. Paul Olsen's Earthscape site.
• Lizard locomotion. Figure 11.6, based on David Carrier's work.
• A running cat. Figure 11.8a.
• A bouncing wallaby. Figure 11.8b.

The Komodo dragon

• The Komodo dragon.

Archosauromorphs

• Image of Late Permian predatory animal Archosaurus
• The lion-sized Garjainia
• Chasmatosaurus skull. Very early archosauromorph. South African Museum.
• The rhynchosaur Scaphonyx.
  • Scaphonyx. Figure 11.9b.
  • Scaphonyx skull. Figure 11.9a.

Orthosuchus, a Lower Jurassic crocodilian.

• Orthosuchus skeleton photo. South African Museum.
• Orthosuchus drawing. South African Museum.

Dinosaur ancestors or close relatives

• Cladogram of Archosauria. Figure 11.12.
• Euparkeria could have been the ancestor of both pterosaurs and dinosaurs later in the Triassic.
• Skull of Euparkeria. Figure 11.11.
• Euparkeria. South African Museum.
• Dynamic image of the anatomy and posture of Euparkeria
• Postosuchus drawing. Paul Olsen's Earthscape site.
• Postosuchus skull. Paul Olsen's Earthscape site.
• Ornithosuchus. Paul Olsen's Earthscape site. drawings
• Ornithosuchus skull. Figure 11.13.
• Fast-running early terrestrial crocodile. Figure 11.15
• Phytosaur. Paul Olsen's Earthscape site.
• Little aetosaur, Stegomus. Paul Olsen's Earthscape site.

The first dinosaurs

• Press release: these are Middle to Late Triassic, from Madagascar, very slightly older than than the Argentine ones, perhaps 230 Ma. We are not talking scientific breakthrough here. 22 October 1999.

Page last updated October 28, 2004.

Links last checked August 27, 2004.

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