Earth has experienced many ice ages throughout its history. During these periods, large parts of the planet were covered in thick ice sheets, and global temperatures dropped significantly. The most recent ice age, known as the last glacial period, ended approximately 11,700 years ago.

Scientists believe that ice ages are caused by a combination of factors, including changes in earth's orbit, volcanic activity, and shift in ocean currents. As glaciers expanded, they shaped landscapes by carving valleys and moving massive amount of rock and soil. Many species had to adapt to the cold conditions or migrate to warmer regions to survive.

Although the last major ice age ended thousands of years ago, some scientists argue that earth could experience another one in the future. However, human activities, such as burning fossil fuels, are increasing greenhouse gases, which trap heat and may delay or even prevent the onset of a new ice age.