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Major Events on Eras - Coggle Diagram
Major Events on Eras
Paleozoic Era
Earth has a very long history but this era started when Earth was formed 4.6 billion years. In the Precambrian time, the only living things were single-celled organisms.
The Cambrian Explosion
In this moment of the era, there was a big leap in evolution. Many organisms some even had outer shells and even skeletons.
First Vertebrates and Land Plants
The first jawless fish evolved. And vertebrate animals also. Plants were grown abundantly on the land in the Silurian period. Invertebrate and vertebrate animals lived in the Devonian sea
Animals Reach Land
Also, the Devonian period was when the first vertebrated animals lived on land, the first was an evolution from the lungfish with muscular fins.
Animals and Plants Evolve further
An amniote egg evolved. This allowed animals to lay eggs without getting dried out. Winged insects evolved into many forms including dragonflies and cockroaches. Plants formed swampy forests.
Pangea
Earth's continent moved slowly moved together to form a great landmass or a supercontinent; this supercontinent was called Pangea.
Mass Extinction
This is the end of the Paleozoic Era when earth's worst extinction happened. Scientists estimate that 90% of ocean life and 70% of land life was extinct. Scientists aren't sure what happened, but some scientists say that many volcanos erupted and that that caused that plants couldn't do photosynthesis.
Cenozoic Era
In this Era mammals had to compete with dinosaursand other animals for food and shelter. The mass extintion made mammals evolve and adapt to diffrent living enviorments.
Mammals Thirve
During this time earths temperature. As continents drifted apart ocean basins widened. Dolphins and whales evolved and some became very large.
Ice Ages
Earth becme warmer and cooler in a cycle. And then Ice ages followed then by warmer periods. In that time 30% of earth was covered in thick ice glacers. The lastest warm period was between 10,000 and 20,000 years ago.
Humans
The quaternary period is sometimes refered as tha "Age of Humans". Homo erectus an ancestor of the modern human appears in the fossil record at the baggining of this era. While modern humans appeared 190,000 years ago. By about 12,000 to 15,000 years ago humans had migrated to every country except antartica.
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