The Precambrian era began at the time when Earth was formed 4.6 million years ago. This era lasted for about 4 000 000 000 years, which is approximately 87% of Earth's history. the Hadean eon, which was 4.6 billion years ago the Archean eon, which begins about a billion years after Earth was formed the Proterozoic eon, which was 700 million years ago
Precambrian shields, such as the Canadian Shield, Brazilan Shield, African Shield, and Australian Shield are formed.
Volcanoes from small islands in long chains, which collide together to from larger islands. These large islands eventually become the core of the continents we know today.
Formations of oceans, atmosphere, and continents.
Oxygen build-up began.
Single-celled and multi-celled organisms
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It has been said to involve a large glaciation event that occurred about 600 million years ago. Because of this event, almost all micro-organisms were completely wiped out.
Later on, the Vendian fauna, also perished in a second extinction event.
The two most accpected hypotheses for the Precambrian extinction are glaciation in the early Ordovician, and cooling and depletion of oxygen in marine waters.
Many paleontologists believe that the Vendian fauna were the progenitors of the Cambrian fauna. However, others believe that the Vendian fauna have no living representatives. Under this latter hypothesis, the Vendian fauna is believed to have an undergone an extinction, after which the Cambrian fauna evolved.
The Precambrian era’s climate differed from eon to eon. In the Hadean eon, Earth was very hot. This is because the heat that was received from the Sun was very low, while the radiation of heat from Earth’s interior was much larger.
During the Archean eon there was high concentrations of carbon dioxide and methane, two strong greenhouse gases that add heat energy to the lower atmosphere. Years later though, temperatures started to drop. Some think this is because of the oxidation process that had been going on for billions of