The Early Dinosaurs-2/8/23

Who are the earliest ancestors of dinosaurs?

Suggest that it was an ornithodiran archosaur

Amniote skull types:

Anapsid, Synapsid, Diapsid, Archasaur

Curotarson ankle:

At an angle relative to the longer bones, this helps with a sprawling stance

Ornithordiran ankle:

Perpendicular to the long bones, this helps with an erect stance

Within ornithidira are the:

Dinosaurmorphs

What is the difference between dinosaurs and dinosaurmorphs?

The perforate acetabulum (hole in the hip socket)

Dinosaurmorphs were?

Small, bipedal, lightly built, carnivorous or inscetivours

The Ischigulasto Formation is where, and from when?

Argentina, 229 MA

The Santa Maria Formation is where, and from when?

Brazil, 233 MA

Dinosaurs in the Early Late Triassic were?

Sparsely distributed on earth

Dinosaurs in the later part of the late Triassic were?

Globally distributed and there were many different types

The two dinosaur groups are?

Saurischian and ornithischian

Saurischian pelvis bone is:

Pubis points are facing forward (lizard like)

Ornithischian pelvis bone is:

Pubis points are facing backwards (bird like)

Feathers are present in both dinosaur groups?

yes, they are present

Feather evolution/Sensory:

Feathers function as whiskers

Feather evolution/display:

Feathers were use for displays, probably very colorful

Feather evolution/insulation:

Developed for warmth because of possible cold bloodiness

Feather evolution/flight:

Pennaceous feathers could have introduced flight