What caused the ice age?
Flexi Says:
Ice ages can have several different causes. Plate tectonics and the position of the continents can influence ocean currents- if large landmasses are near the poles, ice tends to build up and increase Earth's albedo, further lowering the temperature. Recent glacial periods are correlated with slight variations in the Earth's orbit which cause parts of the planet to receive less energy from the sun. Other ice ages in Earth's history have been triggered by changes in the Earth's atmosphere: for example, the evolution of algae 2.4 billion years ago, and of land plants 360 million years ago, both caused a decrease in atmospheric greenhouse gases which cooled the planet.