Appearance and Anatomy Flashcards
Fossil
Any perserved evidence of a prehistoric organism
Adaptations
Traits that have evolved because they serve specific functions
What are the 4 major functions of bones?
- they passively resist gravity and maintain an animals form
- they provide a ridgid framework for muscle attachment
- Bones provide protection
- Bones store mineral reserves
Vertebrates
ANimals that have vertebrae and skulls
Invertebrates
Animals that lack vertebrae
Brain case
Rear portion of skull that is hollow and houses the brain
Nares
pair of openings in the skull for the nostrils
Orbits
pair of openings in the skull for the eyes
Fenestrae
Additional skull openings
Laterotemporal fenestrae
Fenestrae on the lateral sides of the skull
Supratemporal fenestrae
Fenestrae on the top of the skull
What does the laterotemporal/ supratemporal fenestrae do?
Provide extra room for large jaw muscles
Antorbital fenestrae
Third fenestrae between each orbit and naris (function is unknown)
Centrum
The spool or dsik shaped body of the vertebrae
Neural Arch
above the centrum abd it functions to cover the nerual canal
Neural Canal
The opening in each vertbrae where the spinal nerves run
Vertebral processes
Provide attachment surfaces for muscles and sometimes provide articulation surfaces for ribs; 2 types: Transverse and Spinous
Transverse Processes
Extend from the lateral sides of vertebrae
Spinous Processes
Extend upward from the neural arch
Cervical Vertebrae
Vertebrae in the neck, these often have a extra-large opening for blood and nerve channels and they help support the animals head
Dorsal vertebrate
Vertebrate in the back, these often have tall spinous processes and large rib articulation surfaces
Sacral Vertebrate
Vertebrate in the hips, these are fused to the pelic bones forming a solid bone structure called the sacrum
Caudal Vertebrae
Vertebrae in the tail, have chevrons underneath the vetebrae to protect a large blood and nerve channel and provides tail support
Gastralia
Small ribs posisioned across the dinosaurs underbelly
Tetrapods
Animals that evolved from an ascestor with 4 feet and 4 limbs
Limb girdles
Connect the limbs of tetrapods to the rest of the skeleton
Pectoral girdle
part of the skeleton where the forelimbs connect
Scapula
shoulder blade (largest bone in each side of the pectoral girdle)
Pelvic girdle (what is it composed of?)
Where the hindlimbs connect in the skeleton (each side of the pelvic girdle is composed of 3 bones, the ilium, pubis, and ischium)
Acetabulum
depression/ hole in the pelvic girdle into which the hind limbs articulate
What are the arm and leg bones of Tetrapods?
Arm: Humerus, Radium, Ulna, Carples, Metacarples, and phalanges
Leg: Femur, Tibia, Fibula, Tarsles, Metatarsels, and Phalanges
Saurischian
Dinosaurs that share an evolutionary ancestor that has a pubis that extends downward and forward toward the ribcage
means “lizard hipped”
Ornithischian
Dinosaurs that share an evolutionary ancestor that had both a special beak-forming bone in the upper jaw and a pubis that extended downward and toward the tail
This gave them more space in the rib cage for X-large digestive organs (primarly herbivors)
means “bird hipped”
What are the 2 major groups of Saurischians?
Sauropomorphs and Theropods
Sauropomorphs
Large herbivours with elongated necks and reletively small heads
Prosauropods
early group of sauropodomorphs and the first group of large-bodied herbivour dinosaurs to evolve
Sauropods
Large group of Sauropodomorphs, many were a gigantic size, who stood on 4 robust and column like legs. Their vertebrae were filled with air sacs to help reduce weight and they had peg-like teeth
Theropods
Bipedal saurischian dinosaurs that shared a carnivourous ancestor. Many were carnivourous and had sereded, blade-like teeth and a sharp hooked claws (there were some that were herboviours and some lacked teeth)
Birds are types of theropods
What are the 5 major groups of Ornithischians?
- Ornithopods
- Pachycephalosaurs
- Ceratopsians
- Stegosaurs
- Ankylosaurs
Ornithopods
- Lacked armour
- either walked bipedally all the time or assumed a bipedal stance while running
- some smaller and some larger
- Example disnosaurs: Iguanodonts abd Hadrosaurs
The Hadrosaur had a “duckbill” with tightly packed small teeth at the rear of their mouth for large chewing surfaces
Pachycephalosaurs
- bipdeal
- short arms
- very strong tails
- thick domed skull roofs ad backwards inting horns
- have sharp conical teeth in the front of their mouths and leaf shaped teeth in the rear of the mouth
- Example dino: Pachycephalosaurus
Ceratopsians
- have large parrot like beaks and skulls that are greatly expanded in the rear
- Rear skull expansion is taken to a boney frill or neck sheild
- many have large forns and have dental batteries
-Example dinosaur is the Triceratops
Stegosaurs
- Quadrupedal dinosaur with rows of projecting osteoderms
- Example Dinosaur is te Stegosaurus
Ankylosaurs
- most heavily armoured dinosaur
- quadrupedal
- have short legs and a wide ribcage
- backs of these animals are covered in spikey protective osteoderms and some have large osteoderms on their tails forming a “tail club”
- Example dino: Anodontosaurus
Dental batteries
small teeth that were tightly packed at the rear of the mouth (adaptation for large chewing surface in herbivours)
Osteoderms
Bones that develop within the skin and are a common component of animal armour
Integument
body covering
Melanosomes
pigment cells within feathers
What makes a feather black/grey?
long and narrow malanosomes
What makes feathers white?
no melanosomes
What makes feathers Iridecent/ glossy?
narrow malanosomes that are aligned in the same direction
What makes fethers brown/reddish?
Short and wide malanosomes
