Dino Notes - Dino Notes Dinosaurs Group of land living,...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Dino Notes Dinosaurs Group of land living , extinct reptiles lived from 230 to 65 million years ago during Mesozoic era ranged in size from small chicken to giant Argentinosaurus some quadruped (walked on 4 feet), some biped (walked on 2 hind limbs), though primitively bipedal lived all over world most dinos can’t chew, except hadrosaurs (swallowed food whole) est that 1,900 genera of dinos lived during Mesozoic era, 530 valid genera , 60% known from single individual only Reptiles tetrapod (4 feet), vertebrate that: breathes air, scaly skin, short legs relative to body size, relatively small brain, 3-chambered heart, cold blooded, soft-shelled amniotic eggs Cold blooded Warm Blooded -animal has same temp as surrounding -soaks up heat in sun to be active, if cold sluggish -called ectothermic -animal maintains its own temp by metabolic means -expands a lot of energy (from food) to keep temp constant & ready for activity at all times -called endothermic or homothermics 4 fundamental groups 1. Basal or stem reptiles a. No fenestra 2. Anapsida – only turtles a. No fenestra 3. a. b. Extremely sucessful 4. Synapsida – group of extinct reptiles that gave rise to mammals
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
a. One fenestra Archosauria 2 nd node Compared with other diapsid groups, reduced number of individual skull bones (fusion of multiple bones) & opening of fenestrae in the skull Three new characteristics 1. 2. Presence of serrated teeth set in sockets 3. A large proves on the shaft of the femur, trochanter, served as the attachment pt for major thigh retracting muscles Divided into 2 clades 1. Croc like group a. Ankle structure – v. flexible 2. rd node a. b. Dinosauria
Background image of page 2
Defined by characteristics that are associated w/ upright stance & some skull characteristics 1. At least 3 (but most commonly 5) fused vertebrae forming sacrum 2. Expanded ilium of pelvic girdle to attach to the sacrum 3. Pelvic girdle with acetabulum 4. Femur with angled ball joint to fit acetabulum 5. Ribs with 2 heads (attachment to vertebrae) 6. Complex forward facing shoulder girdle Divided into two clades based on arrangement of the 3 hip bones o Ornithischia All herbivores Pelvic structure Leaf-shaped teeth Ossified tendons along backbones o Saurischia ORNITHISCIAN -
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 23

Dino Notes - Dino Notes Dinosaurs Group of land living,...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online