Question about history

So, we read about history for a while, and he likes it...We started with Ice Age...
And now David asks me:
-So, this is when history began, Ice Age?
-No, but is this when the first humans appeared...
-But where were the humans up to Ice Age??
-We belive that the humans developed from monkeys....they were called homo erectus...and then the homo sapiens, humans, descended...
-But, what was before Ice Age? How did they called that time?? If nodoby wrote about it, or draw about it, how do we know what happened???
I didn't had a good answer, so I changed the subject :D

After a few minutes David asks:
-So we descended from the monkeys?? Like the "trunk monkeys"?