The World Before The Dinosaurs

Permian Extinction

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The Permian Period really does end in a bang. Most people don't know of this mass extinction, possibly greater than the one that ended the Dinosaurs. 96% of all sea creatures bacame extinct, and 70% of all land animals died. Possible causes are volcanoes and a greenhouse effect created when a sudden large amount of methane emerged from the bottom of the ocean. This disaster is the line that seperates the mighty Dinosaurs from the Monsters that came before them.

Late Permian Life

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During the Late Permian, the kinds of life living on Earth started to look more like the Dinosaurs. Mammal like reptiles, like Gorgonopsid (The scary looking creature pictured in the event before this.) were built to kill, being the dominant creature on the Earth at that time. There were other creatures too, like the second creature in the event before, which were actually the ancestors of turtles. There were also tiny creatures named Diictodon, which burrowed underground to escape Gorgonopsid.

Permian Period

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Now marks the last period in the Paleozoic Era, the Permian. Early in the Permian period, there are mostly the sailed back creatures like Dimetrodon that are pictured in the title of this timeline. However, during Late Permian, things do start to change. Another new class of animal starts, mammal-like reptiles. As you may have guessed, this class will eventually just be called "Mammals". Similar to the Ordovician, this period will also end in a mass extinction, but we will get to that later.

First Reptiles and Mesothelae

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Between the Devonian and Carboniferous Periods, some amphibians adapted to lay eggs not in the water, but on land. They also adapted a different type of skin that didn't need to constantly be wet. They became the first reptiles. But the reptiles were alerted to a big threat, Mesothelae, a huge spider that looks like something out of a particular Stephen King novel. Scientists say that if Mesothelae were here today, it would be hunting cats. The reptiles will one day rule, but not for a while.

Carboniferous Period

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Today spiders are constantly being stepped on, but there was a period in time where the arthropods ruled the world. This was the Carboniferous Period, a time with great coniferous trees towering above, constant lighting storms, and giant spiders the size of a human head. Maybe now you see why this is the author's favorite period of time in history.

Devonian Period

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All the organisms that lived before the Devonian Period are lucky, because they didn't have to mess with sharks. Yes, sharks have been on this planet for almost 420 million years, and they've barely changed. This is because from the start they were built to be the perfect predator that could hunt any prey. Besides the sharks, the Devonian Period is also famous for the development of amphibians, who could walk on land but had to keep their skin wet and could not lay eggs outside of the water.

Silurian Period

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Quickly moving on to the Silurian Period, this period is most known for the first animals and plants on land. Scientists believe that the first creatures on land were giant sea scorpions, who could walk on the surface for a short time to travel across to different bodies of water or eat anything that washed up on the shores. The first plant was named Cooksonia (pictured) which only grew on the shoreline. They reproduced by spreading spores.

Ordovician Period

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This marks the Ordovician Period, a not as well known period in time, often being overshadowed by the great Cambrian. However, it is the first period of life to end in a mass extinction. This was caused by an asteroid, similar to how the Dinosaurs became extinct.

Cambrian Explosion

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http://www.youtube.com/watch?v=ice47loNmsc Copy URL above for video. During the Cambrian Period, a huge diversity of different organisms began to immerge. The most possible explaination for why there was such a huge popularity boom is because of high levels of oxygen in the ocean, so more creatures could live in a certain area. These creatures later evolved into the arthropods, a class of bugs, spiders, and scorpions

Cambrian Period Begins

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(Note that from now on that the real dates will be the timeline date times one million years ago.)
This marks the beginning of the Cambrian Period, the first Earth period involving life. Organisms as a whole make a huge step forward as they become multicellular, and even some creatures from the Cambrian period are still here today.

The Spark Of Life

Jan 1, 3500

[3.5 Billion Years Ago] Miraculously, bacterial life evolved on Earth. However, this life was very different from the life today. The bacteria were all producers, using photosynthesis to get food. They also all lived underwater because it was just the right temperature and Earth didn't have a stable atmosphere of oxygen back then, due to the Earth constantly being besieged by other protoplanets and asteroids.

Creation Of The Moon

Jan 1, 4400

4.4 Billion Years ago
Just after the Earth formed, a large, Mars sized object named Theia chrashed into the Earth's young surface. Dust and debris was flung up everywhere, forming a ring around Earth. This eventually collected into the Moon.

The Earth Was Created

Jan 1, 4540

4.54 billion years ago, the protoplanetary disk surrounding the sun began to clump together. They started getting bigger and bigger, until the planets we know today were formed. Early Earth would be a very bad place to go to vacation; the chance of an object slamming into Earth was always very high at this time.