Originally Posted by Frownland

This is actually the reason why we know that human activity is a direct factor in this change. Those past periods had clear causes whether it was solar activity, volcanic activity, the dinosaur apocalypse event, Milankovitch cycles, atmospheric changes from algae, etc. The Earth has had its climate change many times, but always with reason, and we are the reason for the current climate change that we're witnessing. Unless you have evidence showing that something else is the cause?