 The Pilbara and Kaapvaal cratons are some of the oldest rocks in the world and they contain well-preserved Archaean microfossils.A series of international drilling projects has revealed traces of microbial life and photosynthesis from the Archaean in both Africa and Australia.The oldest widely accepted evidence of photosynthesis by early life forms is molecular fossils found in 2.7 Ga-old shales in the Pilbara Craton.