Ancient Australian fossils link oxygen levels to early complex life

Researchers analysing rock cores drilled hundreds of metres below ground in Australia identified more than 12,000 fossils of early eukaryotes dating back 1.7 billion years, ScienceDaily Fossils reported. Eukaryotes are complex cells containing a nucleus and membrane-bound organelles. [1]

According to ScienceDaily Fossils, the study revealed that these ancient complex cells inhabited diverse environments ranging from coastal mudflats to the open ocean. However, the microfossils appeared only in geological settings where oxygen was available to support them. [1]

By contrast, oxygen-free environments from the same rock samples contained only simpler prokaryotic microbes, ScienceDaily Fossils reported. The samples used in the research had been stored in trays at an open-air warehouse in Darwin, Australia. [1]

The authors of the study stated that these findings strengthen the theory that available oxygen was a crucial driver for the emergence and spread of complex eukaryotic life on Earth. [1]