Mass Extinction Events Mass Extinctions Archaean Eon Devonian Period Triassic Period Cretaceous Period Magnetic Pole Reversals Miocene Epoch Cryogenian Events Permian Period Paleoarchean Era Ancient Earth Cryogenian Period Archean Eon
Researchers from the University of Mainz identified tube-like structures likely created by microorganisms millions of years ago, though their origin remains a mystery.