week 10 Flashcards
describe:
- the crust
- the mantle
- lithosphere
- asthenosphere
- outer core
- inner core
crust: outermost layer consisting of continents and ocean basins
mantle: viscous layer of the earth bw the crust and the core
litho: outermost layer of the earth (crust + upper mantle)
astheno: viscous layer beneath the asthenosphere but not the core
outer core: layer of molten iron and nick - drives convection
inner core: solid mass of iron and nickel
what was alfred wegener’s contribution to this course?
founded the theory of plate tectonics (noticed the fossils + that S america and africa fit together)
describe pangaea and panthalassa
pangaea: one big supercontinent
panthalassa: u know how there’s only one continent. that means the ocean isn’t split by continents so theres only one ocean
where are diplodocid fossils found?
they lived in the triassic and jurassic - are found all over the world
how do diplodocids and macronarians demonstrate niche partioning?
both were sauropods, but diplodocids were taller and could reach the top of trees
macronarians were shorter but had stronger jaws that could fuck on any vegetation the diplodocids left behind
what were the herbivores of the jurassic period
diplodocids, macronarians, thyreophorans (ornithschians w body armor)
also prosauropods for the first bit, before they were outcompeted by the sauropods
what were the dominant predators of the jurassic?
allosaurids: had rigid vertebrae and longer legs - stiffer spine and stronger legs gave advantages
coelurosaur theropods were around at this time, but they were like dino twinks
obv we dont have pangaea. what happened.
split into laurasia (N. america, europe, asia) and gondwana (S, america, africa, madagascar, india, australia, antarctica) during jurassic period
by the cret, who was the dominant herbivs?
sauropods went extinct in laurasia
in gondwana, the diplodocids died out; the macrononian Titanosaurs dominated
in laurasia, the hadrosaurs were dominant. the titanosaurs were in laurasia, albeit they were rarer
by the early cret, what were things looking like for carnivs?
carcharodontosaurs: big game hunters designed to kill Titanosaurs
allosaurids, descending from the allosaurs of the jurassic
abelisaurs, ceratosaurid theropods which were smaller game hunters
for most of the cret, allosaurids were most successful until the coelurosaurs diversified and we got dudes like the t rex
where are hadrosaurs and ankylosaurs typically found? what’s one weird place they’ve been found?
laurasia and S. america - suggests a land bridge to S. america from N. america at some point
what are the ankylosaur lineages?
anklyosaurids: tail club + backwards pointing horns
nodosaurids: no tail club, but had sick osteoderm spikes on the shoulders
what are the ornithopod lineages?
lambeosaurine hadrosaurs: had a big bony crest for comm
hadrosaurine/saurolophine: soft tissue crests without the sound amp
what are the marginocephalians?
dudes w an overhanging lip of bone at the back margin of the skull
incl pachycephalosaurs and ceratopsians
what coelurosar would become birds? what synapomorphy do they share
maniraptorans, w a special wristbone called the semilunate carpel which allowed the hand to fold backwards
today, birds use it to fold their wings
