The Ice Age theory claims that the ice sheets expanded, and the entire Earth was covered in Ice. But this being true would have a dramatic affect on the future.
The Ice Age would easily kill any animals that couldn't survive the cold whether, along with others that depended on the animals that couldn't live in cold whether. In only less than 10 years, at least 50% of the non- micro species would probably have become extinct because of the Earth being in an Ice Age. As scientists admit, one extinction leads to another. The Ice Age would have also destroyed all of the volcanoes at the time.
The Ice Age would have to have a cause. What could have caused it?
