The blue whale is the biggest animal that has ever lived on planet Earth. During the last ice age there was an abundance of mammalian megafauna as large as all

The blue whale is the biggest animal that has ever lived on planet Earth. During the last ice age there was an abundance of mammalian megafauna as large as all but the largest dinosaurs. What higher oxygen concentrations allowed was mosquitos the size of a DJI drone. No thanks.