The Early Paleozoic

1
(No Transcript)
2
The Paleozoic

• (544-250 million years)

3
(No Transcript)
4
Initial formation of the Appalachian Mountains
5
Early Paleozoic PaleogeographyWarm shallow seas
over central part of North American
continentThe Taconian Orogeny has resulted in
the formation of the ancestral Appalachian
Mountains
6
By middle Paleozoic timethe Appalachian
Mountains have experienced another episode of
uplift, the Acadian OrogenyThe Antler Orogeny
has resulted in uplift of the western part of the
continent
7
Early Paleozoic LifeSponges, bryzoans, tabulate
corals, brachiopods, and trilobites thrived in
warm shallow seas. Graptolites dominate the
surface waters.
8
Phylum Cnidaria (Corals)

• Organization of cells into primitive tissue
• Cells that secret enzymes for digestion
• Nerve sensory cells (cnidoblasts)
• Mobility
• Free-swimming larvae
• Sexual and asexual reporduction
• Colonial and solitary
• Tabulate and Rugose

9
Phylum Bryzoa (moss animals)

• U-shaped digestive system
• Primitive muscles
• Circulatory and nervous system

10
Phylum Arthropoda

• 3/4 of all living organisms-includes insects,
  spiders, crabs, etc.
• Jointed appendages, segmented bodies, chitonous
  exoskeleton, sensory organs
• Fly, crawl, swim
• The trilobites and Eurypterids-cominated early
  Paleozoic seas

11
Eurypterids
12
Phylum Brachiopoda

• Bivalves with bilateral symmetry
• Complex digestive system, circulatory system, and
  nervous system

13
Brachiopods - first organisms with internal
skeletal elements
14
Graptolites

• Planktonic
• Black shales
• Index fossil for early Paleozoic

15
Late PaleozoicRugose corals, bryzoans,
brachiopods and mollusks dominate the sea floor
benthic community while fish become dominant in
the pelagic realm
16
Mississippian Paleogeography
17
Solitary Rugose corals
18
Phylum Mullusca

• Gastropods (snails)
• Bivalves (clams and oysters)
• Cephalopods (squid, octopi, nautiloids)

19
Cephalopods (squid, octopi, nautiloids)First
true pelagic organisms with eyes, jaws and
tentacles-adapted for hunting
20
Coiled Cephalopods
21
Crinoids - were abundant during the late
Paleozoic and typically comprise the main
component of Late Paleozoic limestones (crinoidal
limestones)
22
Evolution Gone Wild
23
Pennslvanian Coal Forests (Gymnosperms- plants
with cones)
24
West Texas Permian Reefs
25
Evolution of Fish, Reptilesand Amphibians
26
Permian Reptiles (amniotic egg, cold-blooded)
27
The Great Permian Extenction
28
The Mesozoic
29
The TriassicA time of Mountain building
(orogeny)in the western U.S
30
The Sonoma Orogeny
31
The Sevier Orogeny (Nevada and Utah)Imbricated
Thrust Faults -crustal shortning, melanges
(jumble) and decollement (unsticking).
32
Triassic Conifers(The petrified forest of
Arizona)
33
Triassic reptiles in conifer/cycad forest
34
Jurassic Dinosaurs
35
Seismosaurus and flying Pterosaurs
36
Jurassic bird Archaeopteryx and Raptors
37
The CretaceousThe Western InteriorSeaway
38
AmmonitesImportant indexfossils for the
Cretaceous
39
Sassafras Leaf fossil from Cretaceous, one of the
early angiosperms (flowering plants). Other
Cretaceous angiosperms included the birch,
sycamore, magnolia, holly, palm, maple and beech
40
Large marine reptiles (Plesiosaurs)
41
Sunset for the Dinosaurs
42
Late Cretaceous Extenction
43
Giant meteor impact - possible cause of
Cretaceous extinctions