Evaluate the geological evidence for so-called ‘Snowball Earth’ glacial episodes in the Precambrian and the hypothesis that these episodes were critical in the evolution of complex life.
Introduction
The importance of this period is that multicellular evolution began to accelerate after the last glacial ended.refbookpage829.The term Snowball Earth refers to the hypothesis that in the distant past, specifically the Cryogenian period (850-630 million years ago), the earth’s surface was entirely frozen from pole to pole. Evidence of a Snowball Earth comes from the presence of glacial deposits around the world that date back to the Cryogenian period (1). See Figure 1 for a temporal depiction of glaciations. Even though the …show more content…
This gives us an insight into the ocean chemistry at the time of the end of the glacial melt as a large amount of carbon from earth into the sea floor. The scientific explanation to this geological formation would be. During the Period of snowball earth, the carbon dioxide which accumulated from global volcanic eruptions that was able to penetrate through the ice, which has little impact on the temperature. The large volume of carbon dioxide build over time would have easily led to the greenhouse effect, raising the temperature of the earth which became the main mechanism to melt the ice as temperature increased …show more content…
Opponents of Snowball Earth claim the model fails to account for temperature changes or a fully functional hydrological cycle, and have found alternative explanations of the characteristics that proponents claim supports the model. Stephen Warren, a professor at the University of Washington, is currently attempting to find data to support the Snowball model by analyzing the albedo, or reflectivity, of different types of ice found in Antarctica; he believes these ice types were found in the tropics during the Snowball event (31). While the study is ongoing, this current work in the field shows that the Snowball Earth model is just a hypothesis that has yet to be shown absolutely correct. More work in the field is crucial to settling this hot