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Late Paleozoic
Carboniferous to Permian
354-251mya
Overview
• Mississippian and Pennsylvanian combine to
make up Carboniferous Period
• Name comes from extensive coal deposits
formed from remains of plants that grew
during this time
• Glaciations during Carboniferous—extinction
• 2 major extinctions in Permian—second one
was greatest mass extinction of all time!
Late Paleozoic marine life
• After the end Devonian extinction, some
organisms never fully recovered (tabulate
corals, stromatoporoids, placoderms)
• Some diversified:
– Ammonoids
– Sharks
– Brachiopods
– Crinoids
– Fusulinids (great diversity in Permian)
– Bryozoans
Late Paleozoic marine life
Mississipian
rocks
Limestone deposition
• Period named for large proportions of limestone
that were deposited in the
• Well exposed in the upper Mississippi valley
• Road cut on I-172 near Quincy, IL
http://www.wiu.edu/users/mflam/virtual/BurlingtonLs/Burlington.html
Pennsylvanian rocks
Coal formation
• Coal is well exposed in the state of Pennsylvania
• Most geologists call the two periods the Carboniferous
and refer to the Lower and Upper Carboniferous
Diorama of
Pennsylvanian coal
swamp
Denver Museum of
Natural History
Life on Land
• More plant fossils in Carboniferous strata than in any
other geologic interval
• Coal deposits formed from plant remains in lowland
swamps
• Coal represents an enormous biomass of plants
• Coal swamp plants:
– Lepidodendron and sygillaria—both are types of lycopod
trees
– Ferns—seed ferns that reproduce by seeds instead of
spores like modern ferns
• Glossopteris was a seed fern!
• Other plants
– Sphenopsids—seed ferns and spore plants
– Cordaites—tall trees; belong to gymnosperm group (cones)
Coal swamp plants
• Lepidodendron
Note leaf scars on the
trunk.
(Trees grew to 30 m
tall; 90 ft).
• Ferns—grew
at the feet of
the trees
forming
undergrowth
• Sphenopsids (like
Calamites) were sporebearing and similar to living
horsetails or scouring
rushes
• Often interpreted as living
in moist areas, even
perhaps standing water
•
(paleoenvironmental information courtesy
of Dr. Richard L. Leary, Curator of
Geology (Paleobotany), Illinois State
Museum)
•Cordaites—fig. 15-10
• Cordaites--primitive trees; no lineage of descendants
survives today
• Example below:
– Strap-shaped leaves which increasing in width from base to
tip
– Leaf veins ran parallel with the long axis of the leaf,
resemble the monocot veins of corn leaves
•Mazon Creek fossils
Fossil web page
Life on Land
http://www.kgs.ku.edu/Extension/fossils/insect.html
• Insects had important ecological roles
– Food for other animals
• Consume and decompose plants and animals
• Insects first appeared in Devonian - wingless.
Wings appeared by the Late Carboniferous.
•
Life
on
Land
Vertebrates--Amphibians
– First appeared Late Devonian
– Aquatic or semi-aquatic
– Eggs and young in water
– Broad spectrum of shapes, sizes, and modes of life.
– Were up to 20 feet in length (but most living
amphibians are small).
http://www.bio.miami.edu/dana/160/160S07_18.html
Life on Land
• Vertebrates--Reptiles
• First appeared in the Pennsylvanian
• First found in Nova Scotia inside hollow
trees filled with sediment
http://www.ucmp.berkeley.edu/vertebrates/tetrapods/amniota.html
http://www.agiweb.org/news/evolution/examplesofevolution.html
Life on land—reptiles
cont.
• Key feature in the origin of reptiles is the
development of the amniotic egg
– Durable outer shell protects embryo from drying
– Egg can be laid on land
– Yolky part of egg provides nutrition; sac contains
embryo and another sac collects waste products.
– Eliminated need to lay eggs in water, allowing
vertebrates to live and reproduce on dry land for
the first time.
– Amniotic egg probably evolved in Carboniferous
– First fossil eggs are early Permian
Paleogeography
• Warm,shallow seas led
to limestone and
evaporite deposition—
fig. 15-17
Middle Mississippian Paleogeography of North America
http://jan.ucc.nau.edu/~rcb7/nam.html
Paleogeography
• Gondwanaland
collided w/
Euramerica—formed
Pangea (not fully
formed until Permian)
• This collision resulted
in the Alleghenian
orogeny—the 3rd
stage of Appalachian
mtn. building
• Global cooling due to
great carbon sinks of
the coal swamps
• Ice age—extinction—
drop in sea-level
Early Pennsylvanian
Paleogeography
• Dry habitats expanded due to the configuration
of the continents—most land was far away
from moisture-providing oceans
Mississippian paleogeography
Pennsylvanian paleogeography
Permian paleogeography