PALEOZOIC ERA KNOWN AS THE AGE OF FISH OR TRILOBITES

Timeframe: 544 million to 248 million years ago Paleozoic Era Life starts in the seas and moves onto land Timeframe: 544 million to 248 million years ago Six periods: Cambrian Ordovician Silurian Devonian Carboniferous-2 periods included Permian

IMPORTANT FACTS This division is known as ANCIENT LIFE   During most of the Era, warm shallow SEAS covered much of the planet. A major geologic event of the Paleozoic was the formation of the super continent of Pangaea.

HOW EARTH LOOKED DURING THE PALEOZOIC ERA

Cambrian “explosion” For reasons unclear, 13 million years after the start of the Cambrian (so 530 my), there was a tremendous diversification of marine life forms, some of which have never been reproduced. Cambrian Explosion – Most major animal phyla are found in the fossil record (mostly aquatic invertebrates with exoskeletons).

LAND (GEOLOGICAL) FEATURES That First APPEARED: Early Plants such as ferns, mosses, and cone-bearing plants like pine-cone trees By the end of the era, seed plants (gymnosperms) were common and began to form creating a forests By the Devonian Period, grass began to grow on land and mountains formed during this era (Appalachian Mtn.)  

Paleozoic Era

ANIMALS/ORGANISMS (BIOLOGICAL) & GEOLOGICAL FEATURES THAT FIRST APPEARED  

Paleozoic Era Cambrian Period (570-500 MYA) Cambrian Explosion – Most major animal phyla are found in the fossil record (mostly aquatic invertebrates with exoskeletons). TRILOBITES APPEARED

Ordovician Period (500-435 MYA) 1st vertebrates - jawless fish (filter feeders) The vertebrate protects the spinal cord, which carries signals from the brain throughout the body. The lamprey of today is a parasite. The hagfish is a scavenger.

Paleozoic Era Silurian Period (435-395 MYA) 1st INSECTS & ARACNIDS) (invertebrates like spiders & scorpions). 1st jawed fish (later evolved into sharks-made of cartilage).

Devonian Period (395-345 MYA) “Age of the Fish” (giant armored fish). 1st fish/ 1ST SHARKS (scales and swim bladder for buoyancy).

Devonian Period (395-345 MYA) 1st vertebrates on land – amphibians Evolved from the lobed-fin fish which include some species of lungfish.

View of Earth—Devonian Period

Carboniferous Period (345-280 MYA) 1st reptiles

View of Earth—Carboniferous Pd

  ANIMALS/ORGANISMS (BIOLOGICAL) & GEOLOGICAL FEATURES THAT BECAME DOMINANT  

Permian Period (280-225 MYA) Pangaea begins to form (Appalachian Mnts; dry climate; ice age in the southern hemisphere) FISH & TRILOBITES WERE DOMINATE AS WELL Early Permian reptiles, Cacops in front & Casea in back. The middle Permian reptile, Anteosaurus.

View of Earth—Permian Period

Mass Extinction The mass extinction that ended the era caused most marine invertebrates as well as amphibians to disappear.
 At the end of this era, more than 90% of all ocean species and 70% of all land species died One of the Big FIVE Mass Extinctions

WHAT CATASTROPHIC EVENT CAUSED THE MASS EXTINCTION??? 3 THINGS 1. volcanic activity 2. Climate Changes 3. lowering of sea levels as Pangaea was forming (convergent boundaries)