Yes, there have been ice ages and natural cycles of climate change.  HOWEVER, what you conveniently fail to mention is the CO2 levels during the time you mentioned hovered between 250-300 ppm.  Since 1950, the CO2 rise has bucked the trend of 50,000 years of repeatable, documented, climate change cycles.  The CO2 level since 1950 has now reached 400 ppm and climbing.  How is that natural?