Lecture Exam 4: Summer 2009 Update 7/12
Chapter 11, 12, 13 Late Paleozoic Earth History, Invertebrate and Vertebrate
Paleozoic Life
The test will cover selected material from textbook Chapter 11, 12 and 13 AND several
pages from Chapter 9.
Ch 9 (Suggested questions to reveiw: 6)
Eukaryotic Cell Evolution: from prokaryotes to eukaryotes through
endosymbiosis
Review text Pages 179-181
Prokaryote vs Eukaryote (Fig. 9.14)
Evolution of complex cell with nucleus containing genetic material and organelles
Advantages of eukaryotes:
specialized cells to perform specific functions
allow for larger organisms
sexual reproduction leads to variations which may be favorable for
adaptation
One of central themes of evolution is that cells became more complex over time.
The evolution of eukaryotic cells
as observed in the fossil record supports this.
Ch 11 (Suggested questions to review: 2, 3, 4, 6, 7, 10, 11, 12, 13, 16)
Figure 10.3 Cratonic sequences will be provided.
Construction of Pangaea:
During the early Paleozoic, Laurentia had collided with Baltica to form Laurasia
This collision is marked by Caledonian orogeny and closed the northern Iapetus
Ocean.
Acadian orogeny – second step in building the Appalachian mountains, affected
present day New England area
Erosion of Acadians into present day New York State formed the Catskill Delta
with coarse sediments nearer the mountain range and
finer sediments away from
the mountain range. The Kaskaskia sea extended to western New York State during the
Devonian.
The northern European counterpart to the North American Catskill Delta is the
“Old Red Sandstone”, a clastic wedge forming on the
other side of the
mountain ranges formed during the collision of Laurasia and Baltica. (Fig. 11.1a and Fig.
11.17)
During the Carboniferous, (Mississippian and Pennsylvanian periods) Gondwana
moved toward Laurasia and rotated clockwise,
causing deformation by folding and
uplift of mountains in a NE to SW direction from the northern Appalachians to the
Ouachita
mountains of present day Oklahoma. The final stage of building the
Appalachians (Allegheny, Ouachita) (Fig. 11.2 a)
By the late Permian Gondwana had sutured to Laurasia, other continents had
joined to Laurasia, and Pangaea had formed.
Pangaea contained most of earth’s land masses and left a huge Panthalassa ocean.
Late Paleozoic events:
Devonian: Kaskaskian Cratonic sequence inundated North America (Fig. 11.4)
with transitional marine-continental boundaries just west of the Appalachian highlands.
Extensive reef development is observed today in western Canada and
western Texas as evidence of the transgression.
Carboniferous mountain building – Cordilleran – Ancestral Rockies were uplifed
by faulting.
Late Carboniferous, inland sea (from Absaroka transgression) caused transitional
delta environments in some areas of the
north-central and eastern U.S. (Fig. 11.8)
Cyclothems: repeated alternations of marine and nonmarine
environments, usually in areas of low relief.
Represent transgressive and regressive sequences at transitional
areas such as present day Gulf Coast deltas and
swamps.
Associated with coal formation in swamps as sea level rises,
floods, buries, then drops and erodes an area; then
repeats the cycle.
Carboniferous – Permian: Growth of glaciation over Gondwana which spread
upwards into the temperate latitudes. (See Fig. 11.2b)
Natural resources of the Late Paleozoic include coal, evaporite deposits (i.e. salt),
and metallic minerals formed during mountain
building.
Ch 12 (Suggested questions to review: 5, 6, 8, 10, 11, 12,)
invertebrate
Cambrian Explosion
Shelly Fauna (shelled organisms) – why so abundant in the Cambrian fossils
record?
archeocyathid – first reef builder – emerged in Cambrian and were extince at end
of Cambrian
Sponges, brachiopods, corals all appear in early Paleozoic
trilobite – arthropod (insect-like marine organism) – abundant in early Paleozoic
– extinct by Permian
planktonic – nektonic – benthic organisms (their marine environments)
sessile (attach to bottom to filter feed)
trophic levels – tiers of food production and consumptions within a feeding
hierarchy = food web
primary producers (autotrophs) – phytoplankton
primary consumers – feed on producers (filter feeders) and secondary consumers
(predators) feed on primary consumers
decomposers – bacteria break down dead organisms not eaten by scavengers
brachiopods (bivalve filter feeders)
Burgess Shale – Cambrian - importance and type of organisms
notochord, arthropod
exoskeleton – advantages for living organism; advantages for fossil preservation
mass extinction – possible causes; THREE extinctions in Paleozoic -- benefits
(see Fig. 12.19 – can you read the chart?)
Ch 13 (Suggested questions to review Q 10, 11, 15)
chordate (has notochord, dorsal hollow nerve cord and gill slits)
vertebrate (a subdivision of chordates)
Fig. 13.5: major fish groups (note lines indicate range)
no need to memorize – figure would be given for interpretation
Devonian – “Age of Fishes”
Which fish types survived to recent time? (loss of shallow habitat at end of
Permian favored adaptation to deep waters)
Jawless fish, jawed fish, ray-finned vs lobe finned
Challenges to animals moving to land (avoid dessication, accomplish
reproduction, mobility, skeletal support, respiration)
Challenges for plants to move (reproduction)
Crossopterygians – lob-finned fish – why important?
amphibian (returns to water to reproduce and can live on land)
Compare lobe-fin fish and amphibian (Fig. 13.11 – note rib cage for lungs)
Tiktaalik rosaea – “missing link” – between fish and amphibian
amniote egg – significant – contains hard shell, food supply -- reptiles could
reproduce completely on land
endothermic (warm blooded – mammals, birds) vs exothermic (cold blooded
organisms – reptiles, snakes)
Permian extinction:
Cause is not clear but there are multiple possible contributing factors.
Effects of formation of a supercontinent:
Collisions of land masses eliminate continental shelf area which
provide warm, shallow marine environments favorable
to Paleozoic
life forms. Significant loss of habitat for marine organisms.
Long, high mountain ranges cause “rain shadow effect” causing a
windy dry interior.