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Guide fossil: Stromatolites. Geological event: The tectonic plates start moving
The supercontinent Rodinia is formed. Climate event: There were many glaciation -
The first type of living beings were unicellular and prokaryotic. These organisms were bacteria, the simplest form of life.
As an example we have the stromatolites, a type of cyanobacteria that are now fossilized and look like rocks. -
The cyanovacteria and the rest of early life started evolving, creating more pluricellularcand eukaryotic forms of life. AS an example of this evolution we can find the Dickinsonia, along other life forms. -
The change of estate of the atmosphere from a reducing atmosphere to a oxidizing atmosphere that happened during the precambrian, allowed the explosion of life thanks to the gigantic amount of oxygen.
Many new species appeard, but ultimately, they would all die during the three firsts mass extintions. -
Guide fossil: Triboleites. Geological event: As Rodiania fragmentates, Pangea is formed.
Sea leve rises.
Higher volcanic activity
Climate event: Global warming.
Many glaciations -
The marine enviroment that was predominet in the precambrian gave way to an explosion of sea life, it was the Age of Fish.
This age ended with the Precambrian and the appereance of amphibians. -
After the millions of life in the sea, the living beings start moving to the land.
Oone of the prime examples are the firts plants. These plants were gymnosperm,in other words, asexual plants because they did not have flower -
The amphibians appeared during the devonian period, around 419 million years ago. It was the first living beings that needed to live on land to search for food, but need the water to lay their eggs, hence their name, from the greek "amphi" (both) and "bios" (life). -
After many years of evolution, during the carboniferous, the reptiles appeared. Their first characteristic to differentiete them from the amphibians, is that the reptiles only live on land, the first animals to do so. These animals are col-blooded, thus they need the sun to warm and be ablo to move.
They would be the main species during the permian period. -
Guide fossil: Amonites Geological event: Pangea brakes. Climate event: Low sea level and high temperatures.
No glaciations -
Plants, just like animals, evolve, but unlike them, the plants evolved but not entierely. Many gymnosperms evolved to be angiosperm. The changes between these types are that the newer form reproduces by pollen that is transported by many factos, like bees, wind or water. The most efective ways are the bees, this is the reasopn behind the colours that this type of flower has. -
After many mass extintions, along with the dinosours, the birds appeared during he jurraic period. Their golden age lasted during the cretaceus, around 145 million years ago. -
Guide fossil: Numulites Geological event: End of the continental drift.
Alpine range is formed.
Formation of the polar ice caps. Climate event: 4 small glaciations alternated with hot periods. -
The early hominids were just like the other types, but for survivasl purpuses, our ancestors started waliking in two legs.The astroloithecus started to exist around 6.000.000 million years ago in modern-day Ethipia.
As time moved on so did the early humans, as they started populating all corners of the Earth and evolving to our today species. -
The first homo sapiens, the current form of the human beings appeared around 300.000 years ago in many places around Africa.
It is the most widely spreaded hominid and can be found in all continents with a population of 7.8 billion people mainly concentrated in southeast Asia.