About 1.2 billion years ago, eukaryotic and multicelled organisms evolved because _____.
oxygen became available from cyanobacteria
banded iron formations developed
meteorite impacts increased
the atmosphere got thicker from volcanic outgassing
About 1.2 billion years ago, eukaryotic and multicelled organisms evolved because _____.
oxygen became available from cyanobacteria
banded iron formations developed
meteorite impacts increased
the atmosphere got thicker from volcanic outgassing