CHAPTER 10 Flashcards
in addition to these continents there are large islands such as
- Greenland
- New Zealand
- madagascar
- southeast asian islands
what did Alfred Wegener notice
noticed that the eastern coastline of South America and the western coastline of Africa looked like two connectable puzzle pieces, that the fossils of many ancient animals could be found in both South America and Africa, and that several geologic formations in South America had seemingly identical twins in Africa.
what did Wagner suggest
Wegener suggested that Africa, South America, and possibly other continents had once been connected and had since drifted apart.
what was a hold in wagners evidence?
Wegener could not offer a convincing mechanism for how land masses as big and as seemingly immobile as continents could move
The thickness of the crust varies but is usually between __ and ___ kilo-meters deep
5 and 25
By comparison to the other layers of the earth, the crust is ____
thin
what’s below the crust
the mantle
the mantle
The mantle is a layer over 2,500 kilometers deep. The uppermost portion of the mantle is solid. Along with the crust, this upper solid portion of the mantle is called the lithosphere. Below the lithosphere is a portion of the mantle called the asthenosphere
lithosphere
The lithosphere is the upper portion of the mantle and is not one unbroken layer, but is actually composed of many discrete pieces, or plates, that fit together
asthenosphere
the asthenosphere is viscous, slowly flowing, and its shape may be deformed under the uneven weight of the lithosphere.
what causes the mantle to flow
The intense heat and pressure at great depths causes the solid mantle to behave like a fluid
the core
The core is primarily composed of iron and nickel and is subdivided into the outer core and the inner core
the outer core
outer core is molten liquid
the inner core
the inner core is a solid ball
what does extreme heat of the inner layers of the earth create ?
creates convection currents in the viscous asthenosphere. Lower portions of the asthenosphere slowly heat, expand, rise upwards, and then slowly cool and sink.
what is effected by the currents caused by the heat of the inner layers
Plates, or pieces of the lithosphere
what causes the plates tome slowly ?
The currents pull along the undersurfaces of the lithosphere’s various pieces
what causes the lithosphere plates to slowly sink and melt below the cool curst.
the cool crust is more solid and dense than the layers below it. this occurs gradually along one of the edges of a plate.
how does molten rock escape
As one edge sinks, a small gap is created along the opposite edge, and, through this gap, molten rock is free to escape. This rock then cools, solidifies, and adds its own mass to the edge of the plate. This cycle continues and, ever so slowly, the newly erupted rock will eventually progress to the sinking edged and be melted once more.
plate techtonics
The movement of the lithosphere
how has Plate tectonics been verified
The discovery of mid-ocean ridges revealed plate edges where new crust was being formed. Studies of mid-ocean ridges show that the crustal rocks on either side of the ridges have indeed been slowly drifting apart.
how can we record the speed of moving plates
Advanced global positioning satellites tracking systems can detect the ongoing movements of the continents and even record their speeds.
what are sites for large pressure releases in the form of volcanic activity and earthquakes and gradual pressure releases.
As plates move, they sometimes come into conflict and collide. The boundary where two plates collide
what can these pressure releases do caused by boundaries within collisions ?
they can build mountain ranges.
Pangaea
By the end of the Permian period and the beginning of the Triassic period, all the world’s continents had collided together and formed the single supercontinent Pangaea
Panthalassa
single super-ocean
what does having a single contingent result in ?
results in during the late Triassic and early Jurassic, dinosaurs all across the world are fairly similar.
which Dinos were found across the globe
Prosauropods and small theropods similar to Coelophysis
Massospondylus
A typical prosauropod
what is an example of Dinos being very similar in different places
dinosaurs from the Jurassic Morrison Formation of the western USA have very similar counterparts in the Tendaguru Formation of Tanzania and the Lourinha Formation of Portugal.
when did the true sauropods appear
very late Triassic
During the Early Jurassic,
- Pangea was still intact
- sauropods evolved to new heights / mass and abundance. (diplodocus)
diplodocus
- very long necks
- front legs much shorter than hind legs.
- whip tails
- elongated skull
- peg-like teeth only at the front of the mouth, not the sides.
Macronarians
- no whipe-like tail
- more robust
- all legs same length
- also had long necks
what other group did diplodocus share the jurassic world with?
Macronarians
Consider the macronarian Camarasaurus and the diplodocid Diplodocus
the snout of Camarasaurus is much shorter, and its teeth are not limited to the front. In fact, the teeth of Camarasaurus line the entire jaw, and the individual teeth are not simple pegs. They are broad, robust, and look like the heads of spoons. While Diplodocus has the mouth of a selective nipper, Camarasaurus has the mouth of a powerful muncher.
where were camarasaurus and diplodocus found ?
in many fossil quarries from the Morrison Formation, in the American West.
the difference between diplodocus and macronarians ?
Diplodocids were adapted to reach high and prune off the most delectable Jurassic foliage, while macronarians were less picky eaters.
niche partitioning.
Two rather similar animals avoided direct competition for food resources
thyreophorans
A group that includes the ornithischians with body armor.
example of thyreophorans
By far the most well-know of the Jurassic thyreophorans was Stegosaurus.
where have stegosaurs been found?
their fossils have been found in Africa, Asia, Europe, and North America
ornithopods
another ornithischian common in the jurassic period.
- small ornithopods had short legs.
example of ornithopod?
Camptosaurus – an early iguanodont
There were giant ______ and ________, both ancient lineages of theropods
megalosaurids and ceratosaurids
the Late Jurassic was a time of ____ _____
predatory change
allosauroids
The allosauroids were different from the big predators that had come before them.
how were allosaurids different from the larger predators that came before them.
- Allosauroids have vertebrae that interlock more rigidly
- spines were held stiffer
- Their legs are also proportionately longer, = faster than either megalosaurids or ceratosaurids.
The allosauroid _______ is known from more fossil skeletons than any other big theropod dinosaur, among most successful of the Late Jurassic’s predators.
Allosaurus
Compsognathus
- smallest known Dino
- more rigid spin and long legs
- is a coelurosaur
coelurosaur
Coelurosaurs are characterized by a long series of sacral vertebrae, narrow hands, and tails with back halves that are skinny, stiff, and lightweight.
it was the _________ that spawned the dinosaurs’ greatest success: birds.
coelurosaurs
During the Jurassic, Pangaea began to split into two massive continents. ______ and ______
Laurasia and Gondwana
Laurasia
Laurasia was the northern of the two and was composed of what we today call North America, Europe, and Asia
Gondwana
Gondwana was the southern of the two and was composed of what we today call South America, Australia, Africa, Antarctica, Madagascar, and India.
By the ____________, there were significant regional differences among the world’s dinosaurs
Early Cretaceous
Iguanodontians, ankylosaurs, and brachiosaurid sauropods were present in ________ and ____________
North America and Europe.
In ______, the dominant theropods were the spinosaurs and carcharodontosaurids.
Africa
In _____, coelurosaurian theropods became common, and the first ceratopsians evolved.
Asia
when did the continents begin to break apart?
By the Late Cretaceous in Gondwana
where did sauropod dinosaurs go extinct and where did they thrive
they went extinct in Laurasia and thrived in Gondwana, however they did change a lot.
The ________ had gone extinct during the beginning of the Cretaceous, and although the ________ survived
diplodocids. macronarians
which macronarians didn’t survive
brachiosaurid macronarians
which macronarians survived
titanosaurs
Titanosaurs
- robust
- broad chests and wide hips
- some had osteoderms
what was Argentinosaurus
a titanosaur
Argentinosaurus
largest creature to walk the earth.
what was carcharodontosaurs named for ?
named for the shape of their teeth, which resemble those of the Carcharodon – the great white shark
carcharodontosaurs
- a type of allosauroid
- bigger head and longer jaws
what was the largest allosauroid ?
Giganotosaurus
Carnotaurus
were Abelisaurs, and the last survivors of the ceratosauroid lineage
where was Abelisaurs limited to
Gondwana
carcharodontosaurs have:
- long jaws with big teeth
- have powerful forearms with large hooked claws
likely preyed on huge titanosaurs
- have powerful forearms with large hooked claws
abelisaurs have:
- short muzzles and proportionately tiny teeth
- had ridiculously short and stubby arms, with small claws
hunted the smaller species of titanosaurs and other less daunting herbivores.
- had ridiculously short and stubby arms, with small claws
where were titanosaurs found ?
abundant in Gondwana
- rare in asia
- only a few species in North America
one of the biggest differences between the Late Cretaceous fauna of Laurasia and Gondwana ??
the relative under abundance of sauropods in the north
Laurasia, ankylosaurs split into two major groups.
Ankylosaurids and Nodosaurids
ankylosaurids are
the ankylosaurs with the famous tail clubs:
- Have large backwards-pointing horns at the rear of their skulls
- Have a short rounded snout at the front.
Nodosaurids are
the ankylosaurs that lacked tail clubs
- have offensive weapons at the other end, in the form of large osteoderm spikes that project outwards from over their shoulders.
- Smaller skulls
- Elongated narrow snouts
__________ flourished in the Late Cretaceous and quickly became the northern hemisphere’s most successful herbivorous dinosaurs.
Hadrosaurs
We have more fossils of ______ and know more about their biology than any other major dinosaur group.
hadrosaurs
mong advanced hadrosaurs, there are two major groups
lambeosaurine hadrosaurs and hadrosaurines
lambeosaurine hadrosaurs
- big crests that were hallow and used for a musical instrument
- this amplified their calls
hadrosaurines
- had solid bony crests
- some had flesh crests
in terms of Laurasian diversity and success, was another group of herbivorous dinosaurs:
marginocephalians
marginocephalians
overhanging lip of bone at the back margin of the skull.
what are the two groups of marginocephalians
Pachycephalosaurs and ceratopsians
where were modern and pritmive ceratopsians found or more common in??
primitive found in Asia and modern in North America
For much of the Cretaceous, the allosauroids were the top predators throughout Laurasia, just as they were in Gondwana. But they were
rivaled by another theropod group
Coelurosaurs
Coelurosaurs
gave rise to T-rex
T-rex
dominated all of Laurasia
- longer legs and stiffer vertebral Columbia
- big skulls and lots of jaw muscles
Ornithomimids
a kind of coelurosaur
- long clawed forelimbs and larger tail
Another group of coelurosaurs developed a highly specialized wrist bone called a _______ ______
semilunate carpal
semilunate carpal and what did it allow?
- crescent shaped bones
- allowed the hand to be folded backwards in a sharp angle
the dinosaurs that possess them are called the _______
maniraptorans
who are maniraptorans
birds, dromaeosaurs ,oviraptorosaurs
oviraptorosaurs
- mostly vegetarian
- lost their teeth in favor of large beaks.
- had cranial crests and fans of feathers
Therizinosaurs have:
- small skulls on the end of long necks
- hind feet with four forward pointing toes
- A backwards-directed pubis
jaws with small herbivorous teeth in the back and a beak in the front.
what was Therizinosaurs mistaken for
a giant turtle
what is Therizinosaurs
therizinosaurs are maniraptoran theropods
faunal interchange
plate tectonics brings continents that were once separate back together. When this happens, dinosaurs from one region can move into another, leading to similar species in both regions.
____ and ____ _______were probably intermittently connected via _____ at this time.
Asia - North America - Alaska
Theropods are represented by
- Tyrannosaurs
- Dromaeosaurs
- Therizinosaurs
- Ornithomimids
- Oviraptorosaurs
ornithischians in both areas include hadrosaurs:
- Ceratopsians
- Ankylosaurs
- Pachycephalosaurs.
- Ankylosaurs
why were temps higher back then?
high volcanic activity and how the continents were all connected.
how did volcanic activity increase the globes temperature?
released large quantities of carbon dioxide into the atmosphere. Carbon dioxide is a greenhouse gas that holds in solar heat.
how did having a super continent increase the globes temperature ?
it affected the circulation of both air and water currents through the polar regions. Ocean currents are extremely important to distributing and moving heat
Gulf Stream
is an ocean current that flows from the Gulf of Mexico to the western coast of Europe. Gulf Stream water is warmed in the Gulf of Mexico and this heat is carried north as it flows
why is antarctic cold
a strong and cold ocean current encircles much of Antarctica, and this current helps to keep Antarctica cold.
were there icecaps or glaciers in the Mesozoic era?
no
dinos discover in the arctic
The Early Jurassic theropod Cryolophosaurus, and the prosauropod Glacialisaurus and small ornithopod Laeallynasaura
Alaska was home to a diverse assemblage of dinosaurs similar to what is found in Alberta, including the:
- Hadrosaur Edmontosaurus
- Tyrannosaurid Albertosaurus
- The ceratopsian Pachyrhinosaurus.
were sea levels different during the Mesozoic era?
yes they were alot higher because there weren’t any glaciers
Late Cretaceous, much of the interior of North America was covered by a massive inland sea. This vast waterway, called the _____ _____ ______, spread from the ____ Ocean to the ____ _ ____
Western Interior Seaway - Arctic - Gulf of Mexico.
Mesozoic, North America was subdivided into two separate island subcontinents
Laramidia and Appalachia
Appalachia
in the east, from which far fewer dinosaurs are currently known.
Laramidia
in the west, from which the majority of North American dinosaur species are known
Because of this ancient sea, Mesozoic marine fossils can be found in parts of Alberta and throughout the American Midwest, WHY??
because these regions were underwater during the Mesozoic.
In southern Alberta, marine sediments called the _____ ______
Bearpaw Formation
