week 1 Flashcards
what is paleontology? how do we measure it? what are some examples, and why are they preserved?
paleontology: study of ALL prehistoric life
study through fossils which are evidence of life (incl things like foot prints, egg shells, poop, etc)
what were the four main functions of bones
- passively resist gravity
- framework for muscle attachment
- provide protection
- mineral stores
dinosaurs are vertebrates. place the following in order
- caudal vert
- cervical vert
- dorsal vert
- sacral vert
- skull
skull, cervical, dorsal, sacral, caudal (sir door sac? idk)
what does it mean to be a vertebrate
have a backbone made of vertebrae (bone + cartilage) that surrounds the spinal nerve cord
which are likely to be bigger - terre inverts or verts?
verts, as they have bones to passively support weight + have stronger muscles
the skull can tell u many things. by observing fossils, what can we learn about
- the jaw?
- the brain case
jaw: type of diet, based on teeth
brain case: size of brain –> dinosaur’s mental capacity
dinosaurs have nares, orbits, and fenestrae. define.
nares: openings for nostrils
orbits: openings for eyes
fenestrate: additional openings idk
what are the three fenestrae dinos had? where were they located? what were their purposes?
laterotemporal fenestrae: the lateral side of the skull (behind the eyes)
supratemporal fenestrae: on the top of the head
antorbital fenestrae: in front of the eyes, but behind the nares
the -temporals provided extra room for bigger jaw muscles
the antorbital fenestrae purpose is unclear - maybe made the skull lighter, maybe warmed air entering the lungs
what are the components of a vertebrae?
the main disk is called the centrum
the neural arch is above the centrum, which covers the neural canal that the spinal nerve runs through
what are vertebral processes, and what are the two we learned?
vertebral process is where the muscles attach on vertebrae
transverse process: lateral side of vertebrae
spinous process: up on the neural arch
what are the unique traits of each vertebrae
- cervical
- dorsal
- sacral
- caudal
cervical: XL openings for blood + nerve channel, must be strong to support weight of head
dorsal: tall spinous processes that each connected with the ribs
sacral: fused to the pelvis to support leg bones
caudal: chevrons (bones that protect the nerve + blood channels)
what is a limb girdle? what is the structure of the important limb girdles?
limb girdle: connects limbs to skeleton
pectoral (shoulder): connects forelimbs to skeleton by way of scapula (socket).
forelimbs consist of humerus, radius/ulna, carpals, and phalanges
pelvic girdle: connects hindlimbs to skeleton by way of acetabulum (socket)
girdle itself is fused with ilium, pubis + ischium
hindlimbs consist of femur, fibula/tibia, tarsals and metatarsals, and phalanges
what do the metatarsals of dinosaurs tell us about movement patterns?
dinosaurs were constantly elevated on their toes (HIGH. HEELS. ON MY TIPPIES)
what do saurischian and ornithischian mean? what are their defining traits?
saurischian: lizard hipped
ornithischian: bird hipped
saur- have forward facing pubis while ornith- have backwards facing pubis (made room for larger guts)
what are the two types of saurischians? what is the secret third type?
sauropodomorphs and theropods
sauropods are the big long neck dudes with air sacs to offset weight
theropods were bipedal carnivores w serrated teeth and hooked claws (would eventually become birds)
secret third saur- is prosauropods which were big but smaller than sauropods. they got wiped out pretty quick bc they got out-evolved
what are the five types of ornithiscians?
ornithopods: bipedal, no armor
- hadrosaurs: duck bill w teeth (dental batteries)
pachycephalosaurs: bipedal w cool as fuck skull
ceratopsians: them triceratops dudes w frills
stegosaurs: osteoderm plates running down back + over shoulders
ankylosaurs: short + wide dudes w protective osteoderms + tail club
define integument. since ur so good at this, give some examples too
something that covers the body (ex. skin, feathers, scales, quills etc)
we obviously can’t look at the colour of dinosaurs. what clues can we use to infer them?
melanosomes, using what we know of bird melanosomes
- white feathers = no melanosomes
- iridescence = particular arrangement of melanosomes
- black/gray = long + narrow melanosomes
- red/brown = short + wide melanosomes
how did large dinosaurs offset their size?
sauropods had air sacs to make themselves lighter
what is the difference between trex and humans in terms of bone anatomy in forelimbs?
we both have/had humerus, radius + ulna, metacarpal structure
however trex only had two fingers, with bones for a middle finger that became vestigial
what was the purpose of trex toes?
second/third/fourth toe supported body weight
what is the purpose of the illium, ischium, and pubis?
illium: where sacral vertebrae connect to the pelvis
pubis: attachment for muscles, in front of the ischium (nearer the belly)
ischium: attachment for muscles, behind the pubis (nearer the tail)
what adaptations did ornithischians have for eating veggies
- beak for chopping off plants
- back teeth specialized for grinding
- backwards pointing pubis to provide more room for a longer gut (more digestion)
what may be the purpose(s) of osteoderms?
- protective
- mineral stores
- heat retention from solar radiation
- attractive (like feathers, in a sense)
