THE PALAEOZOIC ERA (540 mya - 245 mya)
This is divided into six periods namely:
Permian
(about 286 - 245
mya)
Carboniferous (about 360
- 286 mya) - First coal appeared
Devonian
(about 408 - 360
mya) – This is the age of fish
Silurian
(about 438 - 408
mya)
Ordovician
(about 505 - 438
mya) - This is the age of Graptolites
Cambrian
(about 540 - 505
mya) – This is the age of trilobites. More lives
emerged on Earth in this Period
ACTIVITIES
IN THE CAMBRIAN PERIOD
Sea transgression
Mild
climate
Shelled
Marine invertebrates appeared
Brachiopods, sponges, Trilobites,
Gastropods, echinoderms, radiolarians,
appeared
Floating,
Swimming, crawling, clinging and burrowing sea animals appeared
Also evident were: sea cucumbers, starfish, jelly fish, and water
scorpions
Plants in existence were only algae (land
plants were absent)
THE
ORDOVICIAN PERIOD
ACTIVITIES
IN THE ORDOVICIAN PERIOD
Regression of shallow seas
Mild climate
First vertebrates emerged (jawless fishes)
while invertebrates dominated
Southern Continents formed a single land
mass known as Gondwana Land
First fungi emerged
Marked
by high sea levels rise resulting in transgression
Mollusks, cephalopods, crustaceans, corals, bryozoans,
graptolites, trilobites, brachiopods and echinoderms, were present and
dominated the marine environment.
THE SILURIAN PERIOD
ACTIVITIES
IN THE SILURIAN PERIOD
Shell-forming sea animals were in abundance
Vascular Plants appeared on earth
Continents were flooded and flat
Mild climate with stable and warm
temperature
Land scorpions, eurypterids and Sea lilies,
were predominant
Arthropods dominated the continent
Evolution of modern group of Algae and Fungi
Mass extinction of marine organisms
THE DEVONIAN PERIOD
ACTIVITIES
IN THE DEVONIAN PERIOD
Migration of Fishes into the open seas
Folding and mountain-building activities
took place
Violent volcanic eruptions and crustal
movements
Greater
percentage of the land was submerged
Appearance of amphibians and Lunged fishes. This is the
age of fishes, rays and sharks
Primitive vascular plants went into extinction while
modern day seed producing vascular plants appeared
THE CARBONIFEROUS PERIOD
ACTIVITIES
IN THE CARBONIFEROUS PERIOD
Strictly known for coal deposits, Grit
stones, and lime stones
Earth experienced highest atmospheric oxygen levels ever seen on earth
Prominenet fauna were the winged insects
First land vertebrates appeared
Sea
invertebrates
like Corals, Crinoids, Bryozoans, Foraminifers,
Brachiopods, Cephalopods, and Blastoids were in dominance
First Reptiles laid eggs with shells
Prominent flora was Sigillaria
THE PERMIAN PERIOD
ACTIVITIES
IN THE PERMIAN PERIOD
Is known for worldwide continental uplift
and orogenic movements.
Land masses amalgamated into the super continent
(Pangaea) - thereby creating the Appalachians.
Palaezoic
Plants and invertebrates went into extinction
Extinction
of all Trilobites, Blastoids and Graptolites went into extinction
Mass extinctions occurred in this period
Spiriferid
brachiopods, ammonoids, foraminifers and bivalves were prevalent
Cone-bearing
Gymnosperms appeared.
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