GTS paleozoic

1. Paleozoic Era
In geologic time , the Paleozoic Era, the first era in the
Phanerozoic Eon , covers the time between roughly 544
million years ago (mya) and until 245 mya. The Paleozoic or
Palaeozoic Era (from the Greek palaios, "old" and zoe, "life",
meaning "ancient life") is the earliest of three geologic eras of
the Phanerozoic Eon.
The Paleozoic Era spans six geologic time periods including
the Cambrian Period (544 to 500 mya); Ordovician Period
(500 mya to 440 mya); Silurian (440 mya to 410 mya);
Devonian (410 mya to 360 mya); and the Carboniferous Period
(360 mya to 286 mya) (in many modern geological texts,
especially those in the United States, the time of
Carboniferous Period is covered by two alternate geologic
periods, the Mississippian Period [360 mya to 325 mya] and
the Pennsylvanian Period [325 mya to 286 mya]. The final
geologic time period in the Paleozoic Era is the Permian
Period (286 mya to 245 mya).
The onset of the Paleozoic Era is marked by the "Cambrian
explosion," the sudden appearance of numerous fossils .

5. • Tectonics
• Geologically, the Paleozoic
starts shortly after the breakup
of a supercontinent called
Pannotia and at the end of a
global ice age. (
Varanger glaciation and
Snowball Earth).
• Throughout the early
Paleozoic, the Earth's
landmass was broken up into a
substantial number of relatively
small continents. Toward the
end of the era, the continents
gathered together into a
supercontinent called Pangaea,
which included most of the
Earth's land area.

6. • Paleoclimatic studies and evidence of glaciers
indicate that central Africa was most likely in the
polar regions during the early Paleozoic.
• During the early Paleozoic, the huge continent
Gondwanaland had either formed or was forming.
By mid-Paleozoic, the collision of North America
and Europe produced the Acadian-Caledonian
uplifts, and a subduction plate uplifted eastern
Australia.
• By the late Paleozoic, continental collisions formed
the supercontinent Pangaea and resulted in some
of the great mountain chains, including the
Appalachians, Urals, and Tasmans.

8. • Late Paleozoic Tectonic Setting
• The supercontinent Pangea (from the Greek, meaning "all
land") was gradually assembled as the continents collided
during the Late Paleozoic.
• The larger continents (such as North America) grew by the
addition of island arcs and microcontinents around their
edges. Continental collisions caused several orogenies or
mountain-building events in eastern North America.
• Acadian orogeny and Caledonian orogeny
Middle Silurian to middle Devonian.
Laurentia (North America) and Baltica (Europe) collide to
form Laurasia, and a volcanic island arc (Avalon terrane or
Carolina terrane) collides with eastern North America.
• Late Carboniferous
Gondwana (the southern continents, Africa, South America,
India, Australia, Antarctica) and Laurasia collide.
Southern Appalachian mountains form as Laurasia collides
with northwestern Africa (part of Gondwana).

9. • Animal Life
• Paleozoic life is the sudden appearance of nearly all of
the invertebrate animal phyla in great abundance at the
beginning of the Cambrian. A few primitive fishlike
invertebrates, and then vertebrates, appeared in the
Cambrian and Ordovician, scorpions in the Silurian
period, land invertebrates and amphibians in the
Devonian, land reptiles in the Carboniferous, and marine
reptiles in the Permian.
• Amphibians were the dominant vertebrates until the mid
Carboniferous, then climate change greatly reduced their
diversity; meanwhile reptiles prospered and continued to
increase in number and variety by the late Permian.

10. • Plant Life
• Plant life of the Paleozoic era reached its
climax in the Carboniferous, when
towering lycopsid rainforests dominated
the tropical belt of Euramerica. Climate
change caused the
Carboniferous Rainforest Collapse which
fragmented this habitat, diminishing the
diversity of plant life in the late
Carboniferous and Permian.

11. • Climate
• The Ordovician and Silurian periods were
warm greenhouse periods, with the
highest sea levels of the Paleozoic (200 m
above today's); the warm climate was
interrupted only by a ~30 Ma cool period,
the Early Palaeozoic Icehouse,
culminating in the Hirnantian glaciation.

13. • The Mesozoic Era begins at the end of the Permian Period.
Mass extinction had eliminated most of the species of life
that had existed throughout the Paleozoic Era.
• Dating from 245-65mya, the Mesozoic (Middle Animals) Era,
the age of the dinosaurs, mark the beginning of land animals
and plants. During this Era, Gymnosperms (seed bearing
lant) first evolved, invading deep into new territory away from
shores where water was plentiful. As these new plants
moved inland, animals soon followed. The dinosaurs
evolved, flourished in every habitat on land, then re-invaded
the oceans.
• The Mesozoic ended as the dominant dinosaurs died after a
meteor struck the Earth, changing the environment. The first
mammals and birds appeared during the Mesozoic Era,
surviving in specialized niches as the dinosaur continued its
control on most of the available niches.
Mesozoic Era

15. • Geology:
• At the beginning of the Triassic Period, all of the
continents were lumped together into a large continent
called Pangaea.
• There was no Atlantic ocean at this time. Approximately
135 million years ago, this continent broke up into two
major landmasses: Laurasia and Gondwana.
• 45 million years ago, Australia, like South America,
became independent of Antarctica.
• 35 million years later, Gondwana broke up into present-
day South America and Africa. The Indian subcontinent
began its 8000-km journey pursuing Asia.
• The Continents
• By the time of the Mesozoic Era Pangea the super continent
had formed.

16. • Climate During The Mesozoic Era
• Climate in the Mesozoic was generally warm and
wet.
The temperatures, both on land and in the ocean, were
much higher than during the Paleozoic, and climates
were more tropical in nature.
Despite this, the seas were lower, leaving different types
of land masses for life to deal with.
Over all the Mesozoic Era was dryer than in the
Paleozoic Era. There were more deserts and less
marshland.

17. • Animal Life:
• Almost anyone who thinks about the Mesozoic will think "
dinosaur" at the same time. After all, the Mesozoic has
been dubbed "The Age of the Reptiles." Different types
of reptiles existed:
• The Anapsids are the turtles and tortoises. They were
much more numerous then than now.
• Euryapsids included the pterosaurs and the reptiles of
the sea.
• Synapsids, mammal-like reptiles, later declined
drastically, but they evolved into mammals.
• Diapsids include all of the dinosaurs, and other reptiles in
the Mesozoic.
• Dinosaurs were not the only ones, though. Insects had
large developments, the first inconspicuous mammals
appeared, and swimming and flying reptiles conquered
the sea and sky.

19. • During the Mesozoic
Era, when the
dinosaurs lived,
conifers dominated
the landscape. These
slow-growing
evergreen trees and
shrubs probably
constituted the
majority of the
herbivorous dinosaurs'
diets. Conifers were
probably important
food for dinosaurs,
including the large
sauropods.

20. • Glossopteris, a
tree-like seed fern
(Pteriosperm) from
the Permian
through the
Triassic Period. It
had tongue-shaped
leaves and was
about 12 ft (3.7 m)
tall. Glossopteris
was a dominant
plant in Gondwana
(the southern
supercontinent)
early in the Triassic
period.
Williamsonia
sewardiana was a
cycadeoid (a
bennettitalean). It
had a woody stem
and simple leaves.

21. • The animals that developed in the Mesozoic Era needed new body
types to survive the extremes of temperature and moisture.
Amphibians developed respiratory mechanisms that allowed them to
live in or out of the water for extended periods of time. But it was the
reptiles that were better adapted to the warmer dryer conditions. They
developed thick, leathery skin on both their own bodies and their eggs.
The reptiles thrived, dominating the landscape in both size and
numbers. They are known as diapsids. Diapsids are characterized by
having two openings on each side of the skull behind the eyes.
• The dinosaurs evolved from these reptiles and were themselves
diapsids. During the Jurassic and Cretaceous Periods the dinosaurs
ruled the earth.
• Mass Extinction Ends The Mesozoic Era
• Another mass extinction occurred at the end of the Cretaceous Period,
bringing an end to the dinosaurs and many other species. While this
event did not match the Permian Extinction in the destruction of life it
was the second most devastating in the fossil record. It is commonly
believed that an impact of an asteroid was the cause of this event.