"Snowball Earth" refers to a period of time, approximately 650 million years ago, when Earth experienced extreme global glaciations. This resulted in a covering of ice and snow over much of the planet's surface, including the equatorial regions.
The exact mechanisms of how life survived during "snowball Earth" are still being studied and debated by scientists. However, it is believed that certain microorganisms, such as cyanobacteria, were able to survive in pockets of open water and continue photosynthesis to sustain themselves. Additionally, some organisms may have adapted to living under the ice, while others may have migrated to warmer regions.
The extreme conditions of "snowball Earth" are thought to have greatly impacted the development of life on Earth. It is believed that the harsh environment may have led to the evolution of more complex multicellular organisms, as well as the emergence of sexual reproduction. However, more research is needed to fully understand the long-term effects of this period on life.
There is evidence of simple life forms, such as single-celled organisms, before the "snowball Earth" period. Fossil evidence from this time has been found in the form of microbial mats, stromatolites, and chemical signatures. These findings suggest that life existed on Earth before the extreme glaciations.
The exact cause of the end of "snowball Earth" is still uncertain, but it is believed that a combination of factors may have contributed. These include increased volcanic activity, changes in the Earth's orbit and tilt, and the buildup of greenhouse gases in the atmosphere. These factors eventually led to a gradual warming of the planet and the melting of the ice, allowing life to thrive once again.