Cyanobacteria can cluster together into colonies called with some discovered in western australia that are 3.5 billion years old. cyanobacteria produce oxygen and convert sunlight to energy using plants and arthropods did not make the transition to land until near the end of the period. diverse multicellular eukaryotes did not appear until the period. a large multicellular eukaryote requires more to survive than a single-cell eukaryote.