Life on earth faced many challenges during the initial stages. Life faced many challenges like extreme hot climate, toxic gases, acid rains, etc. life survived under all this condition. During the ice age, the earth was like a white snowball. The ice age is also known as the Cryogenian period because of a greater lower degree of temperature. The ice age period has existed between 720-635 million years earlier. Because of the large amount of ice during that period, anyone can think that there was a very less amount of oxygen. If the oxygen is present in very less amount, life can’t grow. But the fossils of this period are evidence that there was the existence of life. So life survived during the ice age and bloomed. According to sedimentology’s Maxwell Lechte, many of the oceans was uninhabitable due to less amount of oxygen created by layers of ice on the top of oceans.
Life during the ice age survived because of the glacial pumps. The glacial pump is nothing but oxygen trapped inside the ice in the form of a bubble. This oxygen goes into the oceans when the ice melts inside the water. The research team studied the formation of iron around all 3 continents. Total, cerium anomalies & iron isotope ratios from glaciomarine surroundings reveal that the waters were extremely oxygen-deprived – but the closer one draws to the ice-shelf foundation line, the more oxidized the credits grow. This eukaryotic life that lived around those aerated water pools would also have wanted food for a living. And this iron may be a clue of the existence of life.
Sweet water is a rich dissolved iron. There is one kind of bacteria which draws the energy from this iron and grows during the entire life. So the iron deposits found near the ice grounding line may be created by this kind of bacteria. There is no hard evidence about this study, but it is one of the closet theory for the evolution of life during the ice age