An ice age is actually not a deep freeze where penguins live in the Bahamas and Africans learn make snowmen. An ice age is simply when global temperatures are just a few degrees below where they are today – barely 10-15 degrees F lower on average. And there have been multiple ice ages throughout history, though five big ones by most agreements. They typically lasted for more than 100 million years. But before you take the wind out of your child’s imaginary sails, you need to point out that even a temperature drop of ten degrees results in glaciers across North America, such as the one that left Cape Cod the shape it is today. And all the extra snow and ice on the ground is water that came out of the oceans, so the sea level drops as much as 300 feet, exposing new land and connecting Alaska with Asia, and England with the rest of Europe. At that point you could literally walk around the world. On snowshoes, anyway. This may have been how humans crossed over from Asia to North America. Lower sea levels combined with lots of extra ice world have made it possible to walk across the Bering Straits from Asia to North America.
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