Young terrestrial planets should tend towards a reducing atmosphere, due to all the rocks and such oxidizing. It took ages for life on Earth to produce sufficie

Young terrestrial planets should tend towards a reducing atmosphere, due to all the rocks and such oxidizing. It took ages for life on Earth to produce sufficient oxygen to switch to an oxidizing atmosphere. We have evidence that Mars did start reducing and switch at some point. That Mars became oxidizing is certainly curious, considering the reason that happened on Earth.