final Flashcards
woooohooooo
4 characteristics of dinos
1) posture: upright
2) skull openings: 2 behind the skull orbit on each side, 4 total (post-orbital fenestra)
3) habitat: terestrial
4) locomotion: digitigrade (walk on toes)
What rocks are most likely to contain fossils?
Sedimentary
4 types of sedimentary rock environments
1) fluvial: river-based (lots!)
2) lacustrine: lake-based (common)
3) eolian: desert/wind
4) deltaic: river/lake (many)
Period names and dates for mesozoic era
Cretaceous (144-65Ma)
Jurassic (201-144Ma)
Triassic (250-201Ma)
What are the target age, type, and paleoenvironemnts for sedimentary rocks?
Age: mid triassic to late cretaceous
Type: sand, mud, clay, silt
Paleoenvironment: lacustrine/fluvial most likely, deltaic/eolian likely
Why aren’t there dinos in Williamsburg?
- the surface sediment is too young
- most surface sediment in wburg is marine
Bonus: they’re rare in all of VA because there aren’t many mesozoic surface rocks in VA
What are the 2 dino hip types and what do the names mean?
- Saurischia (lizard hipped)
2. Ornithischia (bird hipped) - not bird ancestors
What evolutionary novelties define dinos?
- elongate deltopectoral crest on humorous
- brevis shelf on the ventral surface of the post acetabular part of the ilium
- extensively perforated acetabulum
- tibia with a transversely expanded sub-rectangular lower end
- ascending process of the astragalus
- loss of postfrontal (skull roofing bone)
- epiphysis on the cervical vertebrae
Easiest 3 to remember:
- elongate deltopectoral crest on humorous
- extensively perforated acetabulum
- loss of postfrontal
What are the 2 ways to estimate dinosaur weight?
- using skeletal dimensions
measure length, circumference, cross-sectional area of bones and use those to estimate weight - use scale model
build model of known scale, calculate water volume displacement, scale volume up, use density of living croc (0.9 kg/L) to convert to kg
What are dinosaur poo fossils called?
Coprolites
What type of coprolite is most common?
Carnivore ones, phosphatic minerals in bones eaten aid in preservation
What are 3 examples from the Carpenter article for T-Rex scavenger vs predation?
All of them:
- Olfactory: big olfactory lobes mean good smell for carrion or prey (neutral evidence)
- Failed predation marks on herbivores (pro predation)
- Speed: long metatarsals mean long stride and tail can be used for momentum (pro predation)
- Short arms: stress fractures in arms could only be made if using them to capture prey, arms were muscular (pro predation)
- Eyesight: known for sporadic ring, scale means eyes were 4 inches which mean day poor/low vision in the dark (neutral?)
Easiest to remember:
- failed predation marks
- long metatarsals for speed
- stress fractures in arms
3 pieces of evidence for ectothermy, 5 pieces of evidence for endothermy.
Ectothermy:
- lack of respiratory turbinates
- growth rings in teeth like crocs
- lines of arrested growth, similar to reptiles
Endothermy:
- upright posture, only mammals have this
- growth rates more similar to birds than reptiles
- predator-prey ratio more similar to other endotherms
- global distribution more similar to endotherms
- phylogeny: birds are descendants of dinos
- evidence of a 4-chambered heart
What dino group is most likely to be endothermic?
Theropods, they are closest relatives to birds which are endotherms and their energy and activity requirements would require endothermy
1 major dino group in detail (in the answers are stegosaur and ankylosaur but u do u boo) What does the name mean? Stratigraphic range? Geographic range? Diet? Bipedal/quadrupedal? 3 evolutionary novelties
Steggysaur
What does the name mean? “armor bearing”
Stratigraphic range? mid jurassic to early cretaceous
Geographic range? N&S America, Europe, Asia, Africa
Diet? Herbivore
Bipedal/quadrupedal? Quadrupedal
3 evolutionary novelties
1. large and block like wrist bones
2. loss of ossified tendons down back and tail
3. broad and plate like acromial process
Ankles
What does the name mean? “destroyer of shins”
Stratigraphic range? late cretaceous
Geographic range? N America
Diet? herbivore
Bipedal/quadrupedal? quadrupedal
3 evolutionary novelties
1. fusion of first tail vertebrae to sacral vertebrae and ilium
2. rotation of ilium to form flaring blades
3. developmental of dorsal shield of symmetrically placed bony plates and spines