Lesson 9

Question 0

Plate tectonics

Answer 0

The earth moves, plates shift creating movements of continents by millimetres (can move greater distances because of big events- earthquakes)

Question 1

Alfred Wagner

Answer 1

1912 theory that continents fit together. Prevailing thought at the time was that land bridges were submerged just below sea level

Question 2

Earth layers

Answer 2

Outermost layer = crust, 5-25 km thick
Mantle = mobile flowing layer
Outer core = iron and nickel, liquid
Inner core = solid molten, temperature of the sun
Lithosphere = crust and upper part of mantle
Aesthenosphere = part of mantle that flows like play dough

Crust and inner core are solid layers, mantle and outer core are liquid

Question 3

Plate movements

Answer 3

Hot materials rise, cool materials sink, which creates slow moving currents. Solid crust plates sink at edges, pulling continents

Question 4

Earthquakes

Answer 4

Earthquake fault lines occur at edges of continental plates, when two plates collide, slip under each other, overlap, ect

Question 5

Lithosphere movement

Answer 5

Causes earthquakes, volcanoes, oceanic rifts, and mountain formations

Question 6

Pangea

Answer 6

Triassic (240 million years ago)

Panthalassa - giant ocean that encompasses the globe

Question 7

Laurasia

Answer 7

Asia, Europe, and NA (Jurassic 170 million years ago)

Question 8

Gondwana

Answer 8

South America, Australia, Africa, Madagascar, India, and Antarctica
(India and Asia were originally separate, when it collided with Asian the Himalayas were born)
Broke apart in Cretaceous 100 million years ago

Question 9

Dinosaurs and movement

Answer 9

First Dino’s appeared in Triassic 220 mya, while Pangea still existed. Therefore large mixing of Dino’s, where similar types are found all over the world
Once Laurasia and Gondwana split, we see predominant types in each.
Laurasia = tyrannosaurs, pachyceohalosaurs, and ceratopsians
Gondwana = sauropauds, abellasaurs, carcharadontasaurs

Late Cretaceous leads to breakup of continents and further break up of Dino’s, and potentially an increase in number of species

Question 10

Antarctica Dino’s

Answer 10

Cryolophosaurus - frozen lizard - has a unique crest that looks like a snow shovel, but lived in warmer climates,

Antarctic climate was warmer due to an altered ocean circulation (transporting warm water from equator down to polar region)

70 million years ago, Antarctica was attached to Australia, and currents had to go around Australia, and warmed up there

Question 11

Marine fossils on land areas

Answer 11

Sea level was much higher during Mesozoic era (up to 250 meters higher) this created sea ways that spanned areas that are currently covered by land
Sea level was higher because of a lack of glaciation, thermal expansion (warm water takes up more space), and sea floor spreading associated with plate techtonism (basins filling with rock and sediment)
Land area decreased
Interior NA was covered by a seaway
Nearby lakes and oceans create increased precipitation a and smooth out extremes in temperature (decreasing seasonality)

Higher temperatures and sea levels could have increased species diversity

Question 12

Species diversity

Answer 12

Total number of species in an area

Increased due to increased water levels, increased temperatures, and decreased seasonality

Question 13

Jurassic

Answer 13

Golden age of sauropods and long necks

Late Jurassic = thriving diplodocus, macronaroans

Question 14

Macronaroans

Answer 14

High browser, robust, long front legs, long necks,
Spoon teeth lining entire jaw
Not pickey, crunched woody vegetation

Question 15

Ecological niche

Answer 15

How a particular species makes its living, where it fits into the role of an ecosystem

Question 16

Diplodocus

Answer 16

Simple peg teeth, selective nipper, reach high and prune leaves

Question 17

Niche partitioning

Answer 17

Two competing species occupying slightly different niches, diverging to specialize

Question 18

Thyreophorans

Answer 18

Ornithischians with body armour in Jurassic period, grazed in the shadows of sauropauds

Question 19

Theropod takeover

Answer 19

Late Jurassic, large theropods were common, with stiff spines and long legs (ie allosaurus)
Ornitholesies - Turkey sized coelurosaur, long sacral vertebra, short, fast, small predators hunting small mammals, fish, insects, ect.

Question 20

Coelurosaur

Answer 20

Early ancestor of birds

Question 21

Titanosaura

Answer 21

Most robust of sauropods, like argentinosaurus, not easy prey. Largest animal to walk the earth

Preyed on by carcharadontasaurs, named for shark like teeth, had large jaws, largest was giganotosaurus.
Abellasaurs are the last of carcharadontasaurs, they had to adapt a different morphology (short muzzles and small heads, very short arms, wrinkley bone, cranial ornaments for sexual display)

At the end of the Cretaceous period, only Titanosaurs were found in both Gondwana and Laurasia
Abelisaurs = Gondwana,
Stegosaurus = became extinct long before Cretaceous began
Carcharadontasaurs = outcompeted by end of the Cretaceous

Question 22

Ankylosaurs

Answer 22

In Laurasia, split into 2 groups

• ankylosaurids -tall clubs, backward pointing horns
• nodosaurid -large osteoderm spikes, narrow snouts, no tail club

Question 23

Hadrosaurs (new iguonodon in late Cretaceous, most successful herbivorous Dino)

Answer 23

Sophisticated dental batteries, 2 groups, most abundant in Laurasia
Lambeosaurine - big crests, nasal passages amplifying their calls
Cranial instruments with complex ears leads to intricate calls
Hadrosaurine - crestless or lessened crested hadrosaurs, no sound amplification

Question 24

Marginocephalian

Answer 24

Fringe heads Pachyceohalosaurs - domed skulls Ceratopsians - primitive ceratopsians did not look like triceratops, but still had beaks

Question 25

Silurasaurs

Answer 25

Ornitomimides similar to emus but with long claws Maniraptors had a semlilunate carpal allowing delicate folding of limbs Oviraptors - veggie life, no teeth Therizinosaurs - very long claws, mistaken for turtle, small skull and long neck Tyrannosaurus - strongest jaws, social, take extreme adaptations like longer legs and stiff vertebral column. Big heads added weight, compensated by reducing arm size All of the above are only known from Laurasia