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MAJOR EVENTS ON ERAS - Coggle Diagram
MAJOR EVENTS ON ERAS
major events in the Paleozoic era
ANIMALS REACH LAND
In the Devonian period vertebrates started to live on land.
First land vertebrates were lungfish with strong, muscular fins. Amphibians evolved from this fish
Amphibians live part life on land and part life on water
ANIMALS AND PLANTS EVOLVE FURTHER
Following the Devonian was the Carboniferous period in the near end of the Paleozoic era.
The amniote egg evolved during the Carboniferous period. Now animals could lay eggs on land without them drying out.
Reptiles appeared during this period
Also during this period insect with wings evolved into many new forms, like huge dragonflies and cockroaches
Plants formed vast swampy forests
FIRST VERTEBRATES AND LAND PLANTS
The ordovician period is the second second segment of the Paleozoic era
Jawless fish evolved during the Ordovician period
Insects and land plants may have evolved at this time. Plants grew abundantly during the next period (silurian)
plants grew in damp areas but in the next period (Devonian) plants grew in dryer areas.
The Devonian period is often called the age of fish
Main groups of fish, including sharks, were present in the sea. Most fish had jaws, bony skeletons, and scales on their bodies.
PANGEA
In the Paleozoic era continents moved together to form a great land mass like a supercontinent, called Pangea
Pangea caused deserts in the tropics and sheets of ice covering land closer to the South Pole
THE CAMBRIAN EXPLOSION
Life took a big leap forward during the Cambrian period.
Many different kinds of organism evolved
During the Cambrian explosion many new life forms appeared within a relatively short time
At this time all animals leaved in the sea. Many were animals without back bones like jellyfish, worms, sponges, clam-like brachiopods, and trilobites.
MASS EXTINTION
The worst extinction on earth occurred near the end of the Palaeozoic era, in the Permian period.
Scientists estimate that about 90% of ocean species and 70% of land species died.
Scientists think that multiple volcanoes erupted so dust covered sun light. Others say that global warming could have happened. Others think that there was way more carbon dioxide than oxygen so organisms couldn't quickly adapt
MAJOR EVENTS IN THE MESOZOIC ERA
REPTILES AND BIRDS
The Jurassic period happened during the second segment of the Mesozoic era
In the Jurassic period dinosaurs were the dominant land animals. Scientists have identified several hundred different kinds of dinosaurs including herbivores and carnivorous.
oceans and seas were also filled with diverse life forms which included: sharks, rays, giant marine crocodiles, and plesiosaurs
In the late Jurassic period, the first known bird appeared named Archaeopteryx, which means "ancient winged one". It is thought to have evolved from dinosaurs
In the skies also appeared flying reptiles who were called pterosaurs and varieties of insects.
FLOWERING PLANTS
The Cretaceous period was the longest period of the Mesozoic era.
Reptiles including dinosaurs still lived throughout the Cretaceous
birds started to replace flying reptiles because birds adapted better
the evolution of flowering plants (angiosperms) was one of the most important evolution of the Cretaceous period. Unlike conifers, flowering plants produce seeds that are inside a fruit
Many flowering plats that you may know today appeared during this time, like magnolias, figs, and willows
FIRST MAMALS
The first mammals also appeared on the Triassic period
Mammals are vertebrates that controls its own body temperature and feeds milk to their babies
Mammals were very small in the Triassic period, they were about the size of a mouse.
ANOTHER MASS EXTINCTION
Another mass extinction occurred at the end of the Cretaceous period.
Scientist have the hypothesis that an asteroid hit Earth at a time when extreme volcanic activity in the area that is now India had weakened environments
This extinction whipped out half of all plant and animal groups including dinosaurs
AGE OF REPTILES
Some living things managed to survive the mass extinction
Plants and animals that survived were: fish, insect, reptiles, and cone-bearing plants called conifers
This era is often called the Age of Reptile because of their success in this time
The first dinosaurs appeared during the first period of this era called the Triassic period
MAJOR EVENTS IN THE CENOZOIC ERA
ICE AGES
At the start of the Quaternary period large sheets of ice began to appear on Earth's surface.
Earth followed a series of climate change from cool to warmer weathers causing ice ages followed by warmer periods.
During an ice age 30% of earth was covered with thick glacier layers
The latest warm period began between 10,000 and 20,000 years ago. During that time sea level rose and most of the glaciers melted.
HUMANS
The Quaternary period is often referred as the "Age of Humans".
Homo erectus, a human ancestor appeared in the fossil record near the start of the period
Modern humans appeared about 190,000 years ago
About 12,000 to 15,000 years ago humans had migrated to every continent except Antartica.
MAMALS THIVE
This era begins with the Paleogene and the Neogene period
During this periods Earth's climate became cooler over time.
As the oceans drifted apart, ocean basins widened and whales and dolphins evolved
Mammals flourished in land and became bigger, birds did too.
Flowers and grass became more dominant because forests thinned